No need for solar panels - China is doing what Americas and Europeans haven’t.  - Page 1
Forum section: electronics / general

author: DougSpindler
author_rank: Super Contributor
timestamp: December 05, 2020, 05:21:55 am
content: Anyone see what China has done this week? We are one step closer having next generation of nuclear power. They were successful in firing up their HL-2M Tokamak reactor in just less than 15 years. How long did it take the Americans and Europeans to get to this point?China news reports are saying by 2025 they will have the fusion reactor producing, green, clean electrical power.Sounds like there will be very little demand for solar panels in the near future.Can’t wait to hear from the conspiracy theorists who will say energy from nuclear fusion will never work - I’m sure they are working for the solar panel industry..... right?

author: james_s
author_rank: Super Contributor
timestamp: December 05, 2020, 06:02:06 am
content: I'll believe it when I see it. Fusion power has been in the near future for many decades now, and if I had a dollar for everyone who promised great things in just a few years I could retire.

author: jh15
author_rank: Frequent Contributor
timestamp: December 05, 2020, 07:27:29 am
content: shouldn't this be in the snake oil thread?

author: DougSpindler
author_rank: Super Contributor
timestamp: December 05, 2020, 07:39:43 am
content: I'll believe it when I see it. if I had a dollar for everyone who promised great things in just a few years I could retire.That’s called the stock market. - Keep an eye on Nikola Trucks. The CEO of the company, Trevor Milton, pulled an Elizebeth Holmes and is a billionaire. If you too were promising great things such as “free energy” you would have retired decades ago. It sucks to go to school and learn about things like the laws of physics which explains why some things which sound like good ideas are not possible.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 05, 2020, 07:45:22 am
content: Quote from: jh15 on December 05, 2020, 07:27:29 amWhy? Unlike a perpetual motion machine which violates the laws of physics, producing electricity from nuclear fusion isn’t violating any laws of physics. It would only be snake oil if the laws of physics were being broken.

author: jh15
author_rank: Frequent Contributor
timestamp: December 05, 2020, 07:52:56 am
content: ok, i'll give you that.last I heard, multi million dollhairs spent on research reactors only showed the concept.will look into it.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 05, 2020, 06:35:23 pm
content: Quote from: jh15 on December 05, 2020, 07:52:56 amI think I read NIF reached energy parity. That was a huge step. We know the science works, otherwise we would not be here.

author: james_s
author_rank: Super Contributor
timestamp: December 05, 2020, 08:20:13 pm
content: Quote from: DougSpindler on December 05, 2020, 07:39:43 amLook, I'm not saying it's not possible, we all know fusion works since there's a giant fusion reactor floating over our heads every day, but so far after decades of work we still don't have a functional, sustaining fusion reactor here on earth. If somebody ever figures out how to make one work that will be great, but I'm not going to get excited until a functional physical prototype exists that is verified by independent experts to be genuine. Until then it's just vaporware, we've heard "we'll have it up and running in x years" for more than half a century with that date always remaining 5-10 years out from the current date. Saying we'll have it in 5 years is meaningless, we've heard that before. Show me the goods, otherwise it's just more time wasting.

author: nctnico
author_rank: Super Contributor
timestamp: December 05, 2020, 10:36:17 pm
content: Quote from: DougSpindler on December 05, 2020, 05:21:55 amAs usual you are mixing things up. It is just an experimental step in support of the international ITER project (which aims to have a working fusion reactor by 2025). ITER is a collaboration of 30 of the richest countries including China, EU members, Japan, Korea, Russia and the US. So it is not China that made progress, it is the entire ITER collective which made progress.

author: Tom45
author_rank: Frequent Contributor
timestamp: December 06, 2020, 12:02:49 am
content: Well, there may be some sign of progress here.Historically, fusion power has been 10 years away for the last 60+ years. Now, it seems, it is only 5 years away. Maybe for only the next 30+ years?

author: nctnico
author_rank: Super Contributor
timestamp: December 06, 2020, 12:24:19 am
content: Quote from: Tom45 on December 06, 2020, 12:02:49 amWith coal and gas being so cheap and fission working just fine there never was a real incentive to invest in fusion. In todays circumstances it is clear that that there is an urgent need for fusion power. Nuclear energy is on the radar of many governments nowadays so funding is less of an issue. IOW: I strongly doubt it will take another 30 years while 5 seems to be optimistic. I'd say we see fusion power this decade.

author: james_s
author_rank: Super Contributor
timestamp: December 06, 2020, 04:26:01 am
content: If we see a working self sustaining fusion reactor in 10 years then I would predict another 20 years before there are large scale commercialized fusion reactors brought on line delivering power to paying customers. Don't underestimate the amount of time and effort required to develop safe, reliable, commercially viable deployments from a functioning prototype and we are not even to that point yet. Also don't underestimate the amount of friction there will be due to people who don't understand the distinction between fusion and fission, and all of the other pseudoscience fear that will be spreading around. If you think the 5G nutters are bad just wait for the fusion power causes cancer/mind control/is going to blow up the earth/whatever.

author: nctnico
author_rank: Super Contributor
timestamp: December 06, 2020, 11:35:04 am
content: Quote from: james_s on December 06, 2020, 04:26:01 amThe majority will quiet down quickly if they understand the alternative is paying 5 times more for electricity. In the end only a small minority is lead by misguided beliefs. A lot of environmentalist groups like Greenpeace have lost their credibility a long time ago.I still remember Greenpeace wanting to ban Chlorine in the late 80's. Not hampered by any actual knowledge and the fact that hundreds of millions of people depend on Chlorine to provide drinking water

author: Kleinstein
author_rank: Super Contributor
timestamp: December 06, 2020, 12:56:01 pm
content: I somewhat doubt that nuclear fission is a solution that is fast enough. Even the usual maybe in 50 years we have heard for the last 50 years is rather optimistic. It may be enough to get one crude working unit that produces energy. Getting it economic and at large scale is another part.There are 2 more major problems to solve to make affordable energy at a significant scale. Problem 1 is that such a reactor needs a significant amount of tritium. For the current design plans as far target after ITER and DEMO they plan with some 10-50 kg for a single plant, which is something like 20-100 % of the current world reserve. In 30 years the available stuff will likely be less, as it decays faster than new production. To produce new tritium is needs something like modified nuclear reactors, a little like those used by the military. Currently it more looks like Canada is phasing out there CANDU reactors as one of the larger sources for tritium. They hope to produce enough new tritium in the fission reactors to keep the reactor running, but there would be not much excess, possibly not even enough if they don't get 90% up-time. The availability of tritium can limit the speed for expansion. Unless they build massive new fission reactors it would be a rate of at most 1 new fusion reactor every 30-50 years.The second problem is radiation damage from fast neutrons. With the current available materials the inner wall may last a few months, before it needs replacement. This would likely mean first some 1-3 years cool down to let the radioactivity go down. Than remove the still radioactive old parts and rebuilding the large vacuum container inside the coils. Not sure how long the coil wold last. For a smaller unit this can also be limited. The rebuild would cost quite a bit, and in the meantime part of the valuable tritium decays. So one would not need just one reactor, more like a set of 5-10, so that one is operating while the others are in maintenance or cool down.Even with new, much better materials it is nowhere clear the operation would be cheap. The durability would likely still be limited. To get the required up-time one would also need storage for excess produced at night. Chances are high fission energy would be more expensive than PV and wind.The search for new materials can take a long time and it is not clear such material is possible at all. They have hardly started on this - a little for fast fission reactors. AFAIK the plans are to try molybdenum based materials, so not cheap and not easy to work with.Chances are not so bad that nuclear fusion can work, but chances are very low it would be economic. The costs for PV and wind went down faster than expected.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: December 06, 2020, 01:49:19 pm
content: the only thing ITER seems to be so far is a bottomless pit for tax payers money

author: nctnico
author_rank: Super Contributor
timestamp: December 06, 2020, 02:19:26 pm
content: Quote from: Kleinstein on December 06, 2020, 12:56:01 pmNot if you add costs for storage for PV and wind.

author: Bud
author_rank: Super Contributor
timestamp: December 06, 2020, 04:13:25 pm
content: Quote from: nctnico on December 06, 2020, 11:35:04 amThere has never been such drastic reduction in price of alternate services, and will never be . The most you can get is a Christmas card if you switch and that will be it.

author: Marco
author_rank: Super Contributor
timestamp: December 06, 2020, 04:27:38 pm
content: Quote from: nctnico on December 06, 2020, 11:35:04 amThey have a small point, a large part of chlorine chemistry creates highly persistent waste ... that's why industry like it, it creates durable chemicals and materials. At least nature is somewhat adapted to chlorine compounds though. Fluoride chemistry, now that's 99% unsustainable bullshit IMO. From PFAS to SF6, makes PCBs look like a joke persistence wise ... and even if they eventually degrades into simple salts a few millennia from now, fluoride is a no safe dose poison you don't want to raise background levels of. Leave the fluoride minerals which geology has been kind enough to sequester stay sequestered.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 06, 2020, 05:13:09 pm
content: Quote from: Tom45 on December 06, 2020, 12:02:49 amAre those European and American years? Or Chinese years? Things in China take a lot less time then the do in America and Europe.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 06, 2020, 06:22:45 pm
content: Quote from: nctnico on December 06, 2020, 02:19:26 pmWithout storage the much of the energy from fusion would be wasted - at least the mainstream design needs something like 90% up-time to make enough tritium. So they have to run 24/7 if possible - there are likely more than enough not planed downtime. Without storage this would increase the costs by a factor of 2 to 3. So fusion would also need storage (though maybe a little less than for PV). For PV and wind the costs depend on location so PV in the Netherlands may be not that great, but wind should be OK.The costs for power from fusion are not clear, currently we can only get something like a best case estimate. I don't see much reason why it should be cheaper than fission - more likely to be more expensive. The full fusion reactor would need quite a bit more than they have with the current plasma reactors. It needs a relatively thick (some 2-4 m) breading blanket of some high lithium material (can be liquid) around the core. Likely it also need an extra partial beryllium blanket. It also needs a plant to extract tritium from the blanket and recover it from any leaks / pumps and so one. There is not much civil experience in handling tritium.Even with improved materials, the core part would likely not last very long. Chances are one would need at least one in maintenance and one running. It really depends on the new materials how long the reactor would last and how radioactive it gets.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 07, 2020, 02:16:54 am
content: Quote from: Kleinstein on December 06, 2020, 06:22:45 pmAdapting demand to supply solves that problem, which is trivial compared to the technical issues with making fusion commercially viable.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: December 07, 2020, 04:23:41 am
content: Quote from: Kleinstein on December 06, 2020, 12:56:01 pmHere is why fusion won't be deployed too quickly. Kleinstein is both very smart and very well informed, but from spell check, wayward fingers or whatever has interchanged fission and fusion a couple of times in this post. Those less capable than Kleinstein do this even more frequently and the debate gets muddied with Chernobyl and many other confusions. It will be decades or even generations before the public is either well enough informed or complacent enough to let this go forward.

author: BravoV
author_rank: Super Contributor
timestamp: December 07, 2020, 06:02:56 am
content: As I live in tropical country, one thing that I know for sure, these fusion thingy does suck up a lot ... I mean a lot as I heard this directly at local news, "the coconut" our local farmers produce, no, not a typo.The cooked coconut ...References->https://www.iter.org/newsline/116/1681->Building a second sun: Take $10 billion, add coconuts

author: kaz911
author_rank: Super Contributor
timestamp: December 18, 2020, 08:46:57 pm
content: Quote from: DougSpindler on December 06, 2020, 05:13:09 pmChina has big benefits compared to EU/US - people do what they are told, less bureaucracy if it is on the Party to-do list, more IP "borrowed" without consequence, lots of money and people to do the work (if deemed strategic)Btw the UAE took only 10.5 years from contract to turning on their first nuclear power plant (august 2020) - is it not fun how the UAE despite having more sunlight hours and space for solar - put so much money into nuclear? And they still have oceans of oil... They do have some solar plants but they are NOT easy to operate and hardly ever run at full capacity. The heat, sun and sand takes its toll on hardware.Chew on that fact for a bit.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 18, 2020, 10:00:22 pm
content: Quote from: kaz911 on December 18, 2020, 08:46:57 pmThere is a reason why countries in ther Middle East which have plenty of sun don’t bother with solar. Have you seen what a solar panel looks like after a few month? Or more important what the solar output would be? It’s very obvious why UAE went nuclear and didn’t even bother with solar.Do you know in the Middle East you can find air conditioned streets? And indoor ski slopes and snow parks. When you have an unbelievable amount of money from selling petroleum products it’s amazing what can be done. Including fly 8,000 cows from England to the Middle East.

author: Marco
author_rank: Super Contributor
timestamp: December 18, 2020, 11:56:35 pm
content: Meh, teething problems. Robots can clean glass and dealing with heat is just a question of engineering.Storage is a fundamental problem, but PV is getting so cheap that using it just for most of the air-conditioning load on their grid will start making sense (hydronic airconditioning allows for trivial storage through the night). It will be a lot cheaper than going full nuclear.The end of PV cost reductions are nowhere near in sight, Nuclear is only getting more expensive.

author: kaz911
author_rank: Super Contributor
timestamp: December 19, 2020, 01:55:30 am
content: Quote from: DougSpindler on December 18, 2020, 10:00:22 pmDoug - I lived there for 10+ years....But again you do not comment on the main part of the issue - why do you think the UAE invests in nuclear? Has it not tickled your curiosity?I know the people behind the project - the UAE is a small community. I also know the people behind the Masdar Solar.And the dust problems are easy to overcome when you have cheap labour. Dust was not the main issue but just one of many. A bigger issue is the as solar panels get hot - they loose efficiency. Another issue is cable shielding due to UV. If you put the cables in protective pipes - then you get other issues. Masdar have helped develop better heat resistant solar panels but still on a hot summer day - you have maybe 40-50% of nominated output per spec sheet. At ambient 50 deg c - the panel temperature can be more than 90 deg c.And while "on paper" the UAE rarely have ambient > 50 deg c - in reality it happens almost every year. But labour laws says workers needs time off when temperature is > 50 deg c - so officially it is rarely that high... It only happens when someone forgets to press pause on measurements - and then newspaper headlines cries "Climate crisis - UAE > 50c for the first time in XX years" (as you saw this year) - but in the 10+ years we lived there we had 50c + at least 8 of the years.

author: wraper
author_rank: Unknown
timestamp: December 19, 2020, 02:09:27 am
content: What all of the hype is about? They achieved first plasma discharge, so what? Other countries have done that a long time ago. And Chinese were building it using data collected from previous experiments done by others. The problem is to get it running with generating more energy than own consumption.QuoteNews in 1960's likely said exactly the same (ready in 5 years).

author: Kleinstein
author_rank: Super Contributor
timestamp: December 19, 2020, 02:35:01 pm
content: The problem with nuclear fission is that we still don't know if it is a viable option for cheap energy. There is a chance it can work, an as long as we don't know investments in PV and wind are slowed down. Both solutions would need massive investments and they are scared to bet on the wrong horse. The results for the fission experiments are just as good not too call the horse dead.Conventional power companies can have an interest to keep the hope for cheap energy from fission alive, as this would give them an excuse not to start going to renewable energy right now. So there may be big companies behind the hype, even if they are not directly involved. They have a real interest to keep the hope alive even if the game is lost.Anyway the reactor in China is just a research reactor, doing research in collaboration with ITER. So it is no were near solving the big open questions. China may be relatively fast on this step, but it is only a small part of the puzzle.

author: coppice
author_rank: Super Contributor
timestamp: December 19, 2020, 02:43:47 pm
content: Quote from: wraper on December 19, 2020, 02:09:27 amThis is a key problem that happens over and over in reporting. A scientist realistically says a Tokomak will be up and running in 5 years for serious experimentation, but a delusional reporter hears it will be attached to the grid supplying all humanity's needs.

author: coppice
author_rank: Super Contributor
timestamp: December 19, 2020, 02:45:03 pm
content: Quote from: DougSpindler on December 05, 2020, 05:21:55 amJust 15 years? That would be the slowest Tokomak project in history, and they have decades of other people's experience to build upon.

author: Marco
author_rank: Super Contributor
timestamp: December 19, 2020, 04:37:20 pm
content: CIGS does well at high temperature, if the middle east really invested instead of buying technology developed for Europe and the US temperature wouldn't be a problem.With budgets of 10s of billion you can do a fair bit of R&D and you can buy a lot of installed PV.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 19, 2020, 08:04:08 pm
content: Quote from: kaz911 on December 19, 2020, 01:55:30 amI’m no expert, but was just in Qatar. I’m sure you are aware of the “Berlin Wall” blockade that’s going on in Qatar. They solved that by flying 8,000 cows from England. But that’s a story for another post.I saw a solar panel farm in Qatar where the panels were just caked in sand and dust. Never thought about the temperature degradation. I was temperatures in Qatar can reach 50c so they started air conditioner the sidewalks. Something else that is counter intuitive is the swimming pools are air conditioned.Are you following what’s going on in Qatar? They are bundling like crazy. Hotels, apartments, soccer stadiums., roads, and trams and a new metro system just opened. I’m being told with man caused climate change causing seal levels to rise in 75-100 years Qatar will be under water.Here were are in this forum talking about installing solar and “doing things” that are “good” for the planet. Qatar is doing just the opposite. Lights are left on, water fountains are everywhere, and they don’t do any recycling. The amount of plastic bottles they took out is just staggering.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 20, 2020, 02:56:33 pm
content: Quote from: wraper on December 19, 2020, 02:09:27 amNot so long ago, you were admiring the success of a company regarding space flights in a country that took several people to the Moon. But you do not see the success of a country that at the time of flights to the Moon could only grow rice by putting people bent over.

author: wraper
author_rank: Unknown
timestamp: December 20, 2020, 03:17:42 pm
content: Quote from: S. Petrukhin on December 20, 2020, 02:56:33 pmWhy I cannot admire success of the company which has done things no county have ever achieved, and which started from zero? As of this, there was no breakthrough, nor there was some fast pace development, nor this was achieved by some small private company. It's just another country has done something that was done by others a long time ago. They've done it, good for them. However I don't see anything to be excited about.Also don't forget my comment was made in a context of OP bragging as if China had perfected nuclear fusion, while they are just a part of the project involving many countries.

author: coppice
author_rank: Super Contributor
timestamp: December 20, 2020, 03:51:11 pm
content: Quote from: blueskull on December 20, 2020, 03:39:00 pmHL-2M isATokomak, notTHETokomak. Its an important step, as most of them are. It is intended to feed into the ITER work, and even ITER is notTHETokomak. Its just another step in the chain towards something that might one day be a source of power, rather than a drain.

author: DougSpindler
author_rank: Super Contributor
timestamp: December 20, 2020, 04:03:45 pm
content: Quote from: wraper on December 20, 2020, 03:17:42 pmAppears you are purely focused on the small thinks and missing the big picture. It was not that long ago China was building a new coal fired power plant every week. With man caused climate changed they wised-up and realized what a stupid idea that would be. They spent about 10 years working on building a Thorium reactor before realizing like everyone else there are way too many highly technical issues which we have no solution for at this time. Instead it would be better to go after the better prize of nuclear fusion. While you might think that it’s no big deal remember this country of rice growers who gad a one baby limit is now a player in the space program. You remark that they are just duplicating research that’s already been done is a bit silly. What do you expect them to do? Of course they are going to duplicate research which has already been done so they see how it was done so they can build on that knowledge base.Here’s a question for you.... What if China perfects nuclear fusion in 5 years and can build a fusion power plant in 10. Do you think they will give the rest of the world the technology? Or sell it?

author: wraper
author_rank: Unknown
timestamp: December 20, 2020, 04:35:16 pm
content: Quote from: DougSpindler on December 20, 2020, 04:03:45 pmI'll translate a Russian proverb to you. If only this and that, there would be mushrooms growing in the mouth. Equivalent to "If ifs and ands were pots and pans, there'd be no work for tinkers' hands."

author: DougSpindler
author_rank: Super Contributor
timestamp: December 20, 2020, 04:51:58 pm
content: Quote from: wraper on December 20, 2020, 04:35:16 pmWhat can I say but Поговорка - цветок, пословица - ягодка.

author: coppice
author_rank: Super Contributor
timestamp: December 20, 2020, 05:16:50 pm
content: Quote from: blueskull on December 20, 2020, 04:16:20 pmYes, I know this, but DougSpindler (the OP) doesn't seem to. He reads every press release and reads into it a magic cure for all the world's ills. I'm not clear how many iterations of Tokomak China has built, but the quoted 15 years is actually for a succession of projects, reaching the HL-2M machine at this point. Each another step beyond the last. There is a reason why a lot of European physicists can be found in East Asia. There is money available, and few obstacles to getting things done fast.

author: coppice
author_rank: Super Contributor
timestamp: December 20, 2020, 05:29:21 pm
content: Quote from: DougSpindler on December 20, 2020, 04:03:45 pmCan you try to actually READ something beyond press releases about China's energy programs before commenting? China is still building coal fired power stations rapidly, because they are growing so fast nothing else will meet their short term needs. They have also been building nuclear power stations for 30 years. They started with foreign technology, and have since built the necessary home grown expertise. They have parallel work on a variety of fission reactor types - PWR, pebble bed, wave front, molten salt, thorium, etc. As far as I know those programs are all still running, as none has a certain outcome, and fusion is highly speculative. If you think making a thorium reactor work well is a harder problem than fusion, you really haven't looked at fusion. They also built a large solar power industry. They also built a large wind power industry. They have also been working hard on fusion reactors for quite a while. Like any sane player in the energy field with deep pockets, they know they have to play every possible card to have a good chance of a pleasant outcome.Ask any researcher in China about having a fusion power station in 5 years and they'll laugh at you.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 20, 2020, 05:59:48 pm
content: Quote from: wraper on December 20, 2020, 03:17:42 pmI'm sorry, but i think your opinion is biased. I understand that such success in a small country is absolutely impossible, and there is no reason to rejoice in your own success. And the government is constantly pushing the idea that one country is very good when the other two are very bad. It is also convenient to live well without doing anything and get money from the budget.But you are not a stupid person and understand that the world is much more complicated than a simple division into black and white.Rejoice for colleagues who did not know what electricity was in their childhood, and now they have brought a little sand from the Moon, trying to find a new source of energy.

author: wraper
author_rank: Unknown
timestamp: December 20, 2020, 06:11:53 pm
content: Quote from: S. Petrukhin on December 20, 2020, 05:59:48 pmIt's really hard to understand the meaning behind half of what you wrote. But I need to remind you about what you wrote in another thread about Starship, as you mentioned it here. You claimed that nothing new was developed and all of that is reiteration of old technology already made by others. Hypocrisy is the word coming to my mind.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 20, 2020, 06:23:48 pm
content: Quote from: wraper on December 20, 2020, 06:11:53 pmI've said this about a country that long has the technology space at the highest level. Therefore, in this country there are experts, there is literature, there are educational programs, there is a scientific base, there are technological opportunities and industry. And all these resources are not hidden in the closet of NASA, they can be used by any private company. And even get good help from NASA, including material and financial. If you don't understand my english, i can write more accurately in russian - you will understand it better, perhaps.

author: wraper
author_rank: Unknown
timestamp: December 20, 2020, 06:40:53 pm
content: Quote from: S. Petrukhin on December 20, 2020, 06:23:48 pmIt's not about English. It's about what you wrote makes little sense in regards of meaning behind it.QuoteAs if it's that easy, everybody supports you, and pushes money into all of your orifices. Then why other startups failed miserably? Besides them, Rocketlab is the only other private company which managed to launch any real payload, but much later and on much humbler scale though. BTW where is all of that miraculous literature and expertise in Russia? You have pretty much comparable technology compared to NASA and traditional space companies in USA as far as I'm aware.

author: CJay
author_rank: Super Contributor
timestamp: December 20, 2020, 06:53:56 pm
content: Quote from: nctnico on December 06, 2020, 11:35:04 amThey're still at it now.

author: Marco
author_rank: Super Contributor
timestamp: December 20, 2020, 07:21:09 pm
content: I didn't even know my country stopped using Chlorine in drinking water altogether over a decade ago.Not that Greenpeace is doing it for the humans, but for our personal environments a lot of chlorinated compounds (including the ones formed in the water pipes) are generally not a great idea. Too biologically alien to get efficiently degraded and yet still biologically active. Chlorinated drinking water is better than getting cholera but almost certainly worse than Dutch drinking water.Though as I said, I'd start with fluoride chemistry first.

author: wraper
author_rank: Unknown
timestamp: December 20, 2020, 07:42:42 pm
content: Quote from: Marco on December 20, 2020, 07:21:09 pmChlorine will soon react with something else and nothing toxic will be left. We consume a lot of chlorine every day in a form of table salt. Also Greenpiece does a lot of BS which only results in increased pollution. Say their war against PVC which resulted in unreliable cables/chargers filling landfills.

author: Marco
author_rank: Super Contributor
timestamp: December 20, 2020, 08:11:01 pm
content: Quote from: wraper on December 20, 2020, 07:42:42 pmSure.QuoteNah, just because a chemical is stable against biological degradation doesn't mean it's not biologically active.

author: coppice
author_rank: Super Contributor
timestamp: December 20, 2020, 08:16:26 pm
content: Quote from: Marco on December 20, 2020, 08:11:01 pmTable salt is biologically active. Try putting a freshwater fish in it, or removing the salt from a sea fish. I don't want to stamp out salt, though. I suspect there might be negative consequences.

author: Gyro
author_rank: Super Contributor
timestamp: February 09, 2022, 12:20:37 pm
content: Yay, the Oxford JET reactor just produced 59 megajoules of energy over a 5 second period. 60 boiled kettles is enough for a lot of celebratory cups of tea!https://www.bbc.co.uk/news/science-environment-60312633Apparently it validates some of the design decisions that have been made on the new ITER reactor in France.

author: f4eru
author_rank: Super Contributor
timestamp: February 09, 2022, 12:50:27 pm
content: It's more or less infeasible BS to get electricity with a tokamak.The list of roadblocks is extremely long.Also, where the heck should the tritium come from ?

author: Gyro
author_rank: Super Contributor
timestamp: February 09, 2022, 12:53:35 pm
content: QuoteYes, I wondered that. It's a Deuterium - Tritium mix, as planned for ITER.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 09, 2022, 02:04:44 pm
content: Quote from: Gyro on February 09, 2022, 12:53:35 pmThe generation tritium part is one of the parts not yet developed very much and not included in the test reactors.The idea is to have a kind of breading reactor: the fusion generates fast neutrons. With light materials like beryllium 1 fast neutron can generate 2 slower neutrons and with lithium can than bread tritium. So the plan is to have layers with beryllium and lithium rich material to slow down an absorb the fast neutrons and generate tritium. This part is not really new physics, but it is in the way for doing experiments. With a relatively low power an up time tritium production would also be not very efficient. The tritium breeding part is still one that may break the concepts as it es not easy to generate more tritium than is needed to run the reactor.Even under best conditions there will be only little excess tritium to build up new stock for more reactors and to have a reserve for times of stand still when the tritium stock will slowly decay. The current world wide tritium inventory is about enough to operate 2 or 3 of the planed reactors and the tritium production rate in the fusion reactor is expected to generate enough for one more in some 50 years or more. So it would need extra sources of tritium to get a faster build up (e.g. to get the 5 th reactor before 2200). So this is a weak point in the fusion concept.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 09, 2022, 05:31:14 pm
content: That is one reason a lot of "fusion startups" are claiming P-B fusion is the way to go. It's a low neutron reaction that uses readily available fuels. Unfortunately the coulomb barrier and Bremsstrahlung losses are much higher so it seems to me pretty nuts to try that when getting a sufficiently high Q D-T reaction is already so hard.Realistically any widespread use of D-T fusion for power generation is going to require fission reactors acting as tritium breeders. You just hope that once commissioned the fusion reactors can at least be self sufficient. The only real advantage then is that you can put the fission reactors in geologically and supposedly politically stable regions and then transport the tritium to where it is needed. Of course if you are concerned about political stability and nuclear proliferation, tritium is it's own problem so it isn't clear D-T fusion power is an answer to any question in particular. Again: P-B and other types of aneutronic fusion are suggested as solutions but they are even more pie in the sky "50 years away and always will be" than regular fusion.Then there is the issue of cost. Given that we don't even have one functional prototype reactor any cost estimates for fusion power should be treated as wildly speculative but it seems unlikely a fusion reactor is going to cost less than a modern fission reactor, possibly a lot more. But currently nuclear power -- even without costly delays from legal and environmental challenges -- is still going to have a hard time competing with wind and solar + storage. Once we have a bit more experience with the current generation reactors that may come down a bit, but I wouldn't count on it as the history of nuclear power, costs mostly go up. In theory small modular nuclear reactors might reduce the cost of fission plants to something more competitive but there is not going to be small modular fusion reactors, the numbers just don't work out.

author: TimFox
author_rank: Super Contributor
timestamp: February 09, 2022, 06:16:12 pm
content: Power output: historically, "CP1" (the original fission reactor at the University of Chicago during WWII) could make a measly 200 W of power (about two weeks after the original operation), but had to be throttled back to 0.5 W for testing due to radiation concerns. The reactor was dismantled and moved out to the boonies where it could be shielded better.https://en.wikipedia.org/wiki/Chicago_Pile-1Further engineering effort led to the current state of fission power.

author: f4eru
author_rank: Super Contributor
timestamp: February 11, 2022, 10:12:11 am
content: the difference with fusion is that there is no clear scaling possible today, nor in 10 years.The long ist of impediments have no clear solutions.All we do is scaling the research toys.

author: nctnico
author_rank: Super Contributor
timestamp: February 11, 2022, 05:26:04 pm
content: Quote from: f4eru on February 11, 2022, 10:12:11 amIt just needs money and dedication. With that, anything is possible in a decade. Even going from mediocre rockets to putting people on the moon. Fortunately the EU seems to be clearing the road for (long overdue) investments into modern day nuclear power.

author: f4eru
author_rank: Super Contributor
timestamp: February 11, 2022, 05:36:13 pm
content: There is no "modern day nuclear power".Does not exist.

author: TimFox
author_rank: Super Contributor
timestamp: February 11, 2022, 05:42:57 pm
content: Tell that to the United States Navy.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 11, 2022, 06:12:40 pm
content: Quote from: nctnico on February 11, 2022, 05:26:04 pmIf you are talking about fusion, no. It doesn't matter how much money or effort we put into it, we will not have nuclear fusion power in 30 years much less 10 and the path to commercially viable operation is currently not even addressable. Everybody learns the wrong lesson from the Apollo program. When President Kennedy announced the plan to go to the moon by the end of the decade there were already very detailed plans of how to accomplish that. It was still a triumph of science, engineering, and project management but they already had a concrete understanding of what was necessary. While nuclear fusion research has a long term research roadmap, there is no clear path to "commercial nuclear power plant". Just picking something that sounds hard and saying "If we throw money at it we can do this in a decade" is a way to create failure.If you are talking about fission, its certainly possible and it has been done before. The question is just whether it is a good idea from a practical and financial standpoint. My own guess is that if we can cut the costs of nuclear plant construction in half it makes financial sense to have nuclear power provide 15-30% of power for base load generation. In the US that means basically providing replacement power for retirements in the current 20% of the generation mix that is nuclear, and maybe a modest amount of new capacity. That significantly cuts down on the need for renewable energy storage. If we can't cut costs relative to modern projects such as the Vogtle plant in Georgia or the recent Chinese reactor projects which have been better run than the Vogtle project but still plagued by delays and cost overruns, then we are probably better off just keeping existing plants running as long as we can safely so that we don't have to make up the capacity with natural gas.

author: nctnico
author_rank: Super Contributor
timestamp: February 11, 2022, 06:22:38 pm
content: With existing plants you likely mean the coal powered plants. If so, be aware that generating electricity by burning coal is about the worst way possible. Anything (including nuclear) is better from an environment & health point of view. Natural gas is better (low to zero SO2 emissions) but still produces a lot of NOx.Not sure whether fusion is feasible in a short term or not. A lot of the problems are known so finding solutions is a matter of (parallel) effort. When the need is dire, things can be made to move fast. Just look at how quickly Covid-19 vaccines where developed using technology that has not been used before and was deemed to be years away from any practical application.

author: coppice
author_rank: Super Contributor
timestamp: February 11, 2022, 06:25:30 pm
content: Quote from: ejeffrey on February 11, 2022, 06:12:40 pmThe only way to have fusion generation in a decade is to have a rough design for such a power station today. Even an accelerated program would take a decade to refine the design, construct, test and commision a power station. In reality we are far from having a rough design for a practical fusion power station. Even experimental systems yet to be commissioned, like ITER, are not intended to be an outline of a viable design. We need generations beyond that, to reduce the huge energy consumption of the station itself.Quote from: ejeffrey on February 11, 2022, 06:12:40 pmAt least things like the recent Chinese pebble bed reactor means we are seeing more designs focussed on producing safe sustainable power, rather than being spinoffs of weapons work. In the past, only a very few things, like the CANDU reactors, looked like their primary intention was to power civilisation.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 11, 2022, 06:59:24 pm
content: Quote from: nctnico on February 11, 2022, 06:22:38 pmNo, I mean the existing nuclear power plants in places that have them. About 20% of US electricity production is currently nuclear, and I am saying that even if building new nuclear plants is a bad idea we should keep the existing ones (where the capital cost is already paid) running as long as we can so that we don't have to replace the power they generate with natural gas. Coal needs to be shut down ASAP, but we shouldn't do German style accelerated retirement of nuclear power if we can avoid it.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 11, 2022, 07:54:18 pm
content: They do have a a pretty good idea how a power station as the next step after ITER would look like. They have aready plans and a name (DEMO) for it - though this would still not be a full commercial scale power station. I don't think the real weak point of the concept is power needed to heat up the plasma for a start. That gets better when things get larger. They have a good chance to solve this. In my few there are 3 other weak points that are the bigger trouble:One is the radiation damage and thus the time they can run the system before they have to replace major parts, which would shut down the system likely for years and a major rebuild. If they can last 20 year it may be OK, but I am afraid it may be way less, at least with current materials. Here estimates are more like 1-2 year of full operation before they would have to change the first wall and thus the vacuum chamber all the rest is build around.It looks very much like the system would not be cheap and more like way too expenive to be economical. It can still be OK to carry on with the developement to get a good idea on the cost level to be sure to not miss an option, even though the chances are slim and it is not looking good to compete with PV that got so much cheaper over the last years.The final big problem is the tritium: especially in the first years with not so great operational reliablity they would have a hard time to generate enough tritium to get away without an extra source of tritium. Even later the production rate of excess tritium would be slow. This very much limits the rate new fusion reactors could be started. So even If they would have a known working plan for the reactor or even reactors in stock at amazon, the tritium supply would limit the speed on how fast one could start the reactors. With the current estimates the current world-inventory (some 50 kg) would be enough for some 2 reactors. Doubling time for the tritium is not expeceted to be less than 20 years even if things turn out well. So the reactor number 100 would not be before the year 2200 - at best.

author: nctnico
author_rank: Super Contributor
timestamp: February 11, 2022, 09:05:23 pm
content: Quote from: ejeffrey on February 11, 2022, 06:59:24 pmNot sure about that. New nuclear power plants are safer compared to the old models. Not only due to newer, better designs but also because the old ones are typically past their designed life span. There are several very old nuclear reactors in the Netherlands and Belgium which IMHO should be replaced by newer and (much) bigger ones. Yet there are plans to overhaul these once more and keep them running for a bit longer.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 11, 2022, 09:49:52 pm
content: Quote from: nctnico on February 11, 2022, 09:05:23 pmNew nuclear power plants are *designed* to be safer compared to older models, but only a handful exist and they certainly don't have a long track record of safe operation.But the important thing is that regardless of safety, building a new nuclear power plant is extremely expensive and time consuming. Building some with the hope of improving the cost and timeline is worthwhile, but dollar for dollar you get much better reduction of fossil fuels by building wind and solar. Right now, wind and solar capital costs are less than a boiler and steam turbine. This is, they are less than a nuclear power plant without the nuclear part, they can start producing power (and revenue) in a matter of months rather than years, and operation costs are near zero. Storage is still an expensive proposition, but its really hard to justify spending $$$ on nuclear or anything else on a purely economic standpoint right now -- you have to be counting on the cost dropping.

author: nctnico
author_rank: Super Contributor
timestamp: February 11, 2022, 10:11:10 pm
content: As far as I can see storage will always be more expensive when combined with wind and solar. A Tesla powerwall costs 5 times the price to generate 1 kWh of electricity from solar or wind. Nuclear sits at around 5 to 6 eurocents per kWh. It is not realistic to think that storage solutions will become cheaper in the next several decades. Hence it makes economical sense to build nuclear power stations now to bridge that gap.

author: coppice
author_rank: Super Contributor
timestamp: February 11, 2022, 10:21:14 pm
content: Quote from: Kleinstein on February 11, 2022, 07:54:18 pmThat's wonderful.Quote from: Kleinstein on February 11, 2022, 07:54:18 pmOh, so its not a power station. They are just planning the next tranche of experiments before they've even started running the current ones.This is what makes fusion research look so bad to the public. Step by step research moves forwards. Its costly and it moves slowly, but it does make progress, and if it works out well the prize is enormous and very sustainable. However, people, mostly "journalists" (its hard to use that word unqualified for anyone in the current media) and others who can't read very well, keep saying the prize is just around the corner, and we'll see it in the next round of development. When this turns out not to be true the public think they are being scammed.

author: TimFox
author_rank: Super Contributor
timestamp: February 11, 2022, 10:57:51 pm
content: Back to history: after the wartime effort to make experimental fission reactors, with the first test in Chicago in December 1942, the first commercial fission power plant (in the US) was operational in 1958, using a US Navy design.The Manhattan Project essentially spent an infinite amount of money to build The Bomb in a few years. If there were enough money, I assume that after a decent experimental result (not yet), a commercial plant could follow in a reasonable time. If something is "physically realizable", the only real barrier to commercialization is money.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 11, 2022, 11:18:22 pm
content: Quote from: nctnico on February 11, 2022, 10:11:10 pmI don't think 5 to 6 cents are relaistic. I remember an old study around 2000 that called for around 9-10 cents. AFAIR they are building a new nuclear plant in the UK based on a fixed price point of some 16 cents. I think this is still without much money put back for final disposal and ensurance for accidents. So not all costs factored in.Battery type storrage is still in the ramp up phase. So this may very well get cheaper over time, though only for many cycles and thus short time. The bigger problem with PV and wind in central europe is anyway more the seasonal storrage. This would likely be hydrogen as a main technology to add to the limited capacity of pumped hydro. Only a fraction of the PV and wind energy would have to go though strorage.Anyway nuclear (also fusion), when used on a large scale (like in france) also needs storrage, as nuclear works best when running 24/7. Going up and down in power is possible but adds to plant wear and increases the price. One can save on storage in a mix, if you have multiple sources. So some nuclear can be good in the mix.For the fusion reactor the Wikipedia pagehttps://en.wikipedia.org/wiki/DEMOnstration_Power_Plantis a bit outdated, but gives about the plans, obviously a bit behind scedule. So DEMO is planed to produce power, but likely not economic and likely not enough tritium to be sustainable.They need the vague plan all the way to commercial power plant size, but the later steps are obviously not fixed and may change over time.As far as I see it they are at a point that chances are high they could make it work (though they may still fail on the tritium part), but it looks like the price would be rather high. I don't see it as a game changer - more like a barely competative source of rather limited capacity (e.g. < 10 GW by 2100, limited by tritium supplies). So the big prize got a whole lot smaller. It is just a difficult point to call it a stop after so much money spend. Knowing that something does not work is still worth quite a bit, as we can not hope for fusion as a magical solution or see it as a serious competition for PV.

author: SL4P
author_rank: Super Contributor
timestamp: February 11, 2022, 11:30:35 pm
content: If the CERN LHC was going to cause the end of the solar system a few years ago, and 5G is going to cook our collective human eggs…Bring out the foil hats.Imagine what fusion technology is going to do !

author: DougSpindler
author_rank: Super Contributor
timestamp: February 11, 2022, 11:33:42 pm
content: Quote from: f4eru on February 11, 2022, 05:36:13 pmTell that to France, China and the United States.

author: coppice
author_rank: Super Contributor
timestamp: February 11, 2022, 11:37:55 pm
content: Quote from: DougSpindler on February 11, 2022, 11:33:42 pmChina has a modern day nuclear power station - its new pebble bed station. Where is there something modern in France or the US?

author: DougSpindler
author_rank: Super Contributor
timestamp: February 11, 2022, 11:38:56 pm
content: Quote from: coppice on February 11, 2022, 11:37:55 pmDefine modern?

author: dietert1
author_rank: Super Contributor
timestamp: February 11, 2022, 11:47:24 pm
content: The fact that some men visited the moon does not mean we can visit the moon. Mankind will never leave this planet.On this planet we already have a tremendous, reliable fusion reactor nearby. It gives us up to 1 KW per square meter. We have the atmosphere and the earth magnetic field to protect us from radiation damage. No lack of energy, on the contrary - there will be excess heat. To store solar energy (e.g. as food or fossiles) nature also found its methods.Solar panels are a widespread method to convert radiation into electricity. Another method is generating steam and then electricity from solar energy. One of these methods would be needed with an artificial fusion reactor, too.Regards, Dieter

author: TimFox
author_rank: Super Contributor
timestamp: February 11, 2022, 11:50:48 pm
content: That fact that some men visited the moon means that we can visit the moon, if we spend enough money.It does not necessarily imply that we can live on the moon, since there are some problems that money might not solve.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 12, 2022, 12:04:42 am
content: Quote from: dietert1 on February 11, 2022, 11:47:24 pmDieter I like what you are saying. "We have the atmosphere and the earth magnetic field to protect us from radiation damage." With the atmosphere and the earth's magnetic field to protects us from radiation damage we should build as many nuclear powerplants as fast as we can. I'm for it.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 12, 2022, 12:15:19 am
content: Quote from: DougSpindler on February 11, 2022, 11:33:42 pmThe US does not have any modern day nuclear power. The most recent two reactors to enter service started construction in 1973. We have two uncanceled reactor projects under construction that will hopefully be operational in the next few years. Behind that no other reactors will become operational for at least a decade under any circumstances, and given the cost and delays of those two reactors we don't exactly have people lining up to build more. Realistically it's 15-20 years before new nuclear power could have a significant impact on US energy production. It doesn't matter how good of an idea it is, it's too late.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 12, 2022, 01:16:05 am
content: Quote from: ejeffrey on February 12, 2022, 12:15:19 amThis is true if business as usual is continued. If Global Warming is indeed an existential threat the regulatory and financing hurdles could be set aside, supply chain issues steamrolled etc. An open Manhatten project if you please, but without the need to learn the physics first. But at least in the minds of US regulators Global Warming is a far lesser threat than nuclear proliferation, nuclear waste disposal and union jobs. If that balance ever shifts a lot of nuclear power could come on line in five years (plus or minus a couple).

author: ejeffrey
author_rank: Super Contributor
timestamp: February 12, 2022, 05:19:00 am
content: The regulatory and financial issues aren't the problem. The Vogtle units 3 and 4 had no significant regulatory or legal delays and had the benefit of huge load guarantees. The problem was that it was terrible project management, the plants were of a new design, the design was problematic and not actually complete, and that nobody still working knew how to make reactors new or old, and that the supply chain didn't really exist.All that is surmountable, but it takes time. We could build a lot of nuclear power plants in 5 years but those 5 years can't start now.Also it isn't reasonable to wave away the financial costs but then insist that renewable energy is not cost effective. The US deployed almost 40 GW of renewable energy *last year*. That's nameplate capacity, average will be about 25% of that. This is as much average power as 10 "modern" nuclear reactors. Expectations for 2022 are over 70 GW. That's another 15+ nuclear reactors. Per year. This is a functional industry with a working supply chain. None of that includes storage, which is of course going to be necessary. It isn't needed right now because renewable energy producers can sell almost every kWhr they produce at the time of production so they don't need to store excess, but with 100s of GW peak production coming online soon that won't be true for long. Storage is expensive, but it's a problem that we have working commercial solutions for, albeit at a relatively small scale -- but not zero like modern nuclear. $200 / kWhr for lithium ion battery storage is expensive but it is a real world cost not some power point presentation from the nuclear industry. If you want to pick something that you are going to do a 5 to 10 year cost-is-no-object "engineering Manhattan project" to fight climate change you would have to be a lunatic to pick nuclear power over wind+solar+battery storage.I was right with you all on nuclear 10 years ago. Back then it looked like nuclear was going to be the only feasible option for base load generation. But in 10 years the cost and risk estimates of nuclear has gone way up while we have seen a legitimate revolution in alternative energy -- and you shouldn't really call it alternative anymore given how dominant it is in new energy production.

author: Simon
author_rank: Unknown
timestamp: February 12, 2022, 01:12:34 pm
content: The only cheap method I see of storing excess renewable is converting it to hydrogen and using it later to go back to electricity or use it for any remaining gas supply required.Would nuclear fusion be fast reacting to demand? Current fission cannot be turned up and down in a hurry. We either make our renewables very reactive or have to keep using CCGT that can be adjusted with the few stored water generators we have to manage fluctuations in demand.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 12, 2022, 01:20:52 pm
content: THe fusion reactors would likely need to run 24/7, alone to keep the tritium production running and offseting its natuaral decay. Too much downtime would require additional tritium. So fusion power would likely also have some storage when ever uses as the main source.The fission power plants can turn down and up to some degree. However it may not be with it as it is extra stress to the plant and the extra fuel costs for running 24/7 are not that high.With favorable geology pumped hydro or variable used hydroelectric power can be cheap storrage too, but with a limited capacity and not available everywhere.

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2022, 01:32:59 pm
content: Quote from: Simon on February 12, 2022, 01:12:34 pmIn the Netherlands the plan is to use hydrogen storage for solar, wind AND nuclear.

author: Marco
author_rank: Super Contributor
timestamp: February 12, 2022, 02:41:08 pm
content: Quote from: Simon on February 12, 2022, 01:12:34 pmIt's so expensive that we could dream about some alternatives.Maybe electricity consuming microbes which exude oil could be created/evolved with Adaptive Laboratory Evolution. (GM to get them started exuding a little, then have a massively parallel forced evolution project, ie. hundreds of thousands of bioreactors with radiation and automated testing of caloric content of oil after a production cycle, failures get slagged/purged, successes get spread, all automated).Oil and propane are far more useful energy storage than hydrogen.

author: wraper
author_rank: Unknown
timestamp: February 12, 2022, 05:37:07 pm
content: Quote from: Simon on February 12, 2022, 01:12:34 pmWasting at least half of the energy during storage is not cheap. Hydrogen fuel cells are neither cheap or long lasting too. Burning the hydrogen is even less efficient.

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2022, 06:11:16 pm
content: Quote from: wraper on February 12, 2022, 05:37:07 pmAt the current state of technology that is... and batteries are very expensive per kWh stored as well today. In the end efficiency doesn't matter; cost does.However, we don't need hydrogen storage today and research shows that hydrogen storage will be cheaper compared to batteries for timeframes spanning more than several hours in the next decade. Hydrogen also scales up better for storing really large amounts of energy. Enough to serve as a buffer that can supply energy to the entire country for weeks or months. In the NL several underground salt caverns are being prepared for hydrogen storage.

author: Kim Christensen
author_rank: Super Contributor
timestamp: February 12, 2022, 06:17:03 pm
content: Quote from: nctnico on December 06, 2020, 02:19:26 pmI would be nice if the pro nuclear folk would also take into consideration the long term costs of dealing with nuclear waste.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 12, 2022, 06:22:40 pm
content: There are lots of potentially great storage technologies that are a far better use of climate change focused R&D dollars than nuclear. But we have the technology today to build a (nearly) fossil fuel free grid. In the US we could do it in 10 years as long as we don't let the dream of unproven research distract deployment of boring reality. If one of those new storage technologies works out or nuclear becomes cost effective to build, that's just a bonus.

author: TimFox
author_rank: Super Contributor
timestamp: February 12, 2022, 06:45:34 pm
content: If an essentially "free" source of power (except for the very important cost of capital investment) become available (subjunctive mood used here), then the important question is storage method. Detailed cost analysis is required, not handwaving.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 12, 2022, 06:46:13 pm
content: Quote from: Simon on February 12, 2022, 01:12:34 pmHVAC and hot water can use thermal storage. Since those are the majority of load in most areas, it would be a very cheap solution for a very large part of the problem. And what needs to be done to get that built is to provide incentive to do so, which programs like Ohmconnect are doing.

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2022, 07:20:08 pm
content: Quote from: Kim Christensen on February 12, 2022, 06:17:03 pmKeep it stored for 100 years in a containment building to let it cool and shed most of the radioactivity,dig a hole in the ground and put it in there. Done. It is not like a nuclear power plant produces gigantic volumes of problematic radioactive waste anyway. And if you are concerned about putting toxic materials in the ground: read up where asbestos goes... yes, that is buried into the ground as well and will remain toxic until this planet stops rotating.

author: dietert1
author_rank: Super Contributor
timestamp: February 12, 2022, 07:20:53 pm
content: QuoteI'm not. The atmosphere helps against UV and the magnetic field helps against particles ("sun wind"). Both are of little help in the death zones around Tchernobyl and Fukushima. I'm afraid any effort on reviving fission plant technology will stop with the next meltdown. The rate of meltdowns seems to be like one every 30 years. Or less with more plants. Bad and expensive.Maybe this fits here:The sun gives us all the energy we need. Our lab gets fed by solar panels and we only use a fraction of what they produce. Some years from now authorities will force us to install a storage unit - no problem. Maybe we can use the battery of an electrical car for illumination and TV during night.Regards, Dieter

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2022, 09:13:43 pm
content: Quote from: dietert1 on February 12, 2022, 07:20:53 pmNot really. You can find tons of Youtube videos of people doing stupid things with dangerous items. The reality is that measured by deaths per kWh generated nuclear power is extremely safe. Surprisingly: even safer compared to wind and solar!

author: dietert1
author_rank: Super Contributor
timestamp: February 12, 2022, 09:39:50 pm
content: You are welcome to show the source of your insight about the death risk.I thought it fits as those physicists died trying to find the magic recipe for maintaining a fission configuration critical yet under control. The concept of moderation was invented later. Until now i never heard of moderation in the context of fusion. Instead they ignite extremely small bombs, so the energy released is near useless.Regards, Dieter

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2022, 10:00:54 pm
content: Quote from: dietert1 on February 12, 2022, 09:39:50 pmhttps://www.statista.com/statistics/494425/death-rate-worldwide-by-energy-source/There is a more extensive document from the WHO IIRC but Google won't bring it up just quickly.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 12, 2022, 10:09:18 pm
content: Quote from: dietert1 on February 12, 2022, 09:39:50 pmWith fusion there are different concepts. One is like igniting small bombs with a laser. Much of the energy released would be in the form of hard radiation and fast neutrons, that it planed to be converted in a thick layer of lithium rich material to generate the tritium needed to run the fusion. That lithum ritch layer (AFAIR some 2-5 m ) is also getting most of the heat.The other concept is the magnetic confinement (e.g. ITER). Here it would be a more contineous burn over a longer time (in current tests more like seconds and less and for a power plant planed to be more like 10s of minutes, maybe hours). Much of the slow, gradual progress is in getting longer burn times and this way a better ratio of the energy release to the energy needed for ignition.There would be some kind of moderation of the neutrons to generate the tritium - they essentially need a layer with beryllium to convert 1 fast neutron to 2 slower neutrons to get enough breading action. The lthium layer also does both a slow down first and mainly on a later collision absorb the slowed down neutrons. However the moderation is not effective in controling the fusion reaction, only for the breading part.

author: TimFox
author_rank: Super Contributor
timestamp: February 12, 2022, 10:54:52 pm
content: Quote from: dietert1 on February 12, 2022, 09:39:50 pmModeration (with graphite and cadmium control rods) was used by Fermi in CP1 (1942), based on work done in Europe and the US just before the War.Yes, some physicists did die in accidents during the wartime effort:https://www.atomicheritage.org/history/atomic-accidents

author: DougSpindler
author_rank: Super Contributor
timestamp: February 12, 2022, 11:47:36 pm
content: How can anyone complain about nuclear waste when compared to the massive destruction coal mining has caused. Coal mining has permanently destroyed more land and made more places uninhabitable than nuclear. Yes we've had a couple of nuclear accidents but compared to coal mining and deaths from "green" power nuclear has proven to be the least deadly. Yes we have two forbidden zones when it comes to nuclear, but compare that to the thousands of uninhabitable zones where coal mines are burning out of control and have been in the case of Centralia Pennsylvania for over 60 years.Compare the energy density of nuclear compared to gas, oil solar, wind etc. Nuclear is the clear winner and we have currently have a 650 year supply of it. Since we decided not to blow each other up what are we going to do with it? Might as well use it.As for battery technology, where are you going to get the raw materials to make the batteries? If you are thinking of Lithium, where's all of that Lithium going to come from? How are you going to mine it in an ecology friendly manor? All of the other storage battery methods require raw materials/elements which are far too costly for the scale we need.Brings us back to nuclear.

author: nctnico
author_rank: Super Contributor
timestamp: February 13, 2022, 12:09:02 am
content: It seems China has it's fair share of underground coal fires as well:https://chinadialogue.net/en/energy/6296-the-world-s-longest-burning-fires-china-s-unseen-story/

author: Kim Christensen
author_rank: Super Contributor
timestamp: February 13, 2022, 12:30:34 am
content: Quote from: nctnico on February 12, 2022, 10:00:54 pmRight on the page you linked: "This death rate is based onmining extraction operationsas well as the actual use of energy" so your argument that nuclear powergenerationis somehow "safer" by quoting this stat doesn't hold water. Plus, the coal/nuclear ratio in the 3rd world isn't comparable to the 1st world further skewing the numbers...

author: nctnico
author_rank: Super Contributor
timestamp: February 13, 2022, 12:59:35 am
content: Quote from: Kim Christensen on February 13, 2022, 12:30:34 amPerhaps you should dig a little deeper first. This information is so easy to findFor example: In the Netherlands alone more people died due to pollution from electricity generation using coal than all nuclear power plant accidents combined world wide.https://www.dutchnews.nl/news/2018/11/thousands-a-year-die-from-effects-of-pollution-in-nl-study/

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 02:08:06 am
content: Yup. When presented with all of the facts nuclear is cleaner, safer and more energy dense AND produces 24 hrs a day every day. Can't say that about wind, solar or hydroelectric.

author: Simon
author_rank: Unknown
timestamp: February 13, 2022, 09:50:59 am
content: While I would prefer renewables nuclear does seem to be better than fossil fuels while we have no alternative, that still does not negate the need for storage though, once you have storage you can put in as much renewables as you like.

author: staticresident
author_rank: Newbie
timestamp: February 13, 2022, 10:05:30 am
content: The energy distribution system will never be reliable enough to make solar panels obsolete.I do look forward to cleaner electricity generation. Maybe one day we can get rid of natural gas completely.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 13, 2022, 10:48:36 am
content: Quote from: DougSpindler on February 13, 2022, 02:08:06 amThis is just one study based on the relatively limited statistical data. Chances are the study has some bias and is paid by someone.The comparison is also tricky has nuclear is relatively new and safety standards vary quite a bit between countries and with time and conditions. In the last years things got better, but given adverse conditions (e.g. social unrest, famines, a severe pandemic or war) there may be less careful operation of nuclear plants and things can get a lot worse.The whole waste problem is also not included, as there is currently essentially no finally stored waste - though already some nuclear waste leaking out from the early military operations and waste piles from mining operations.Counting the deaths is also tricky, as radiation and pollution induced effects or quite controiversial. The number of deaths from the Chernobyl desaster varies a lot depending on the sources. So the statistics is at least open to debate and the error bars are huge (e.g the deht toll may as well be 10x higher if you take the estimate from the other extreme).Energy dense is tricky : if you only count the 0.3 mm thickness of PV cells that acrually absorb the light, PV is not that bad. As long as it is not to extreme it does not matter and too locallized is also bad as it means the potential for a big desaster if things go wrong.Producing the energy 24/7 is only a partial advantage - there is still about half the power at times when it is not really needed.Nuclear is still quite expensive and the uranium supplies are too limited to replace coal.

author: Marco
author_rank: Super Contributor
timestamp: February 13, 2022, 12:51:57 pm
content: Unless EU or US put in a trillion dollar scale order for nuclear plants in the next couple of years there won't be an industry which can deliver nuclear at scale by 2030-2050 (also not pie in the sky molten salt dissolved fuel bullshit, or worse molten sodium bullshit ... the nuclear industry loves molten sodium to death, its own death).PS. in the Netherlands if EU NOx emission rules aren't suspended building nuclear plants is going to be hard too.

author: Marco
author_rank: Super Contributor
timestamp: February 13, 2022, 12:57:35 pm
content: Quote from: Kleinstein on February 13, 2022, 10:48:36 amAs I've said before, I think part of the future is flexible PV which is simply rolled out on the ground, with no grading other than removing rocks. Then use some expanding foam in the plastic backing to give them an angle and stake it all down. Minimum resource use per m2 of solar. Robots to keep it clean, medium voltage strings to reduce copper.There are still huge cost reductions possible for PV when land is cheap.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 01:10:59 pm
content: We have a 650 year supply of nuclear fuel left over from those 150,000 nuclear warhead the and Soviets created. Since we decided not to blow each other up, what should we do with it? Seems pretty stupid not to use it to deplete it. Otherwise we will have store it. And since this is weapons grade/enriched it’s going to remain hot for much longer than fuel grade nuclear materials.Something else to think about is nuclear power is 100% natural. The Earth naturally created the first nuclear reactor in Africa long before we were around.

author: nctnico
author_rank: Super Contributor
timestamp: February 13, 2022, 01:22:50 pm
content: Quote from: Kleinstein on February 13, 2022, 10:48:36 amEven if the number of deaths from nuclear power generation are a factor of 100 off, then coal is still -at least- 1000 times worst. That is the baffling aspect of still using coal; the adverse effects just doesn't make the headlines because it is not a single massive incident nowadays. Sure things have improved after incidents like thesehttps://en.wikipedia.org/wiki/Great_Smog_of_London. But still, less people get killed in car accidents nowadays...

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 01:26:35 pm
content: Quote from: DougSpindler on February 11, 2022, 11:33:42 pmThe French "modern day nuclear plant" that finally finished* here, more than a decade late, more than doubling(!) in construction time and costs to what was promised, being one of the most expensive buildings of the mankind ever**, is a demonstration of the problems, and the massive gap between marketing promises and reality. As a result, it also produces some most expensive electricity ever, similar to wind power. We can only hope the safety is actually better than with the old plants, because that's literally the only feature which is supposedly better, with the whole original point, cheap electricity, being devastated.* probably? It's still not producing. It was supposed to be connected to grid in 2009. We still get news of it getting more late, every month. It's still a valid concern it never actually finishes!** (it's 2nd in the Wikipedia list with inflation adjusted prices:https://en.wikipedia.org/wiki/List_of_most_expensive_buildings)Partial reason for the explosion of costs was that authorities demanded fixing all or at least most serious safety concerns during the building. If same type of plant seems to finish significantly faster elsewhere, I would be somewhat concerned.Modern-day nuclear power is expensive, because the standards for risk taking have changed (this can be seen in all modern-day living, think about requirement for airbags), and because any large construction is more expensive than it used to be in the Golden Days. The only reliable shortcut is the good old bribing, but this comes at the expense of security.I believe that economically and CO2-wise, running the old nuclear plants as long as possible is the best bet, but it is obvious such extensions do not come without risk. (This is also one of the things where I can say that this would be wise from one viewpoint, while not myself agreeing with the idea that it should be actually done).Therealityis that significant part of new nuclear projects are failing catastrophically (in commercial sense, hopefully not in accident sense!). To be able to show a few counterexamples does not change the fact that committing into such projects is a massive risk.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 01:39:09 pm
content: Quote from: TimFox on February 12, 2022, 06:45:34 pmIt already does, it's PV and possibly in decreasing degree, wind. The big challenge really is in the storage already.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 01:41:40 pm
content: Quote from: nctnico on February 12, 2022, 07:20:08 pmOh boy if it was just 100 years. It appears you are many orders of magnitude off. That's the problem. 100 years would be still barely manageable.But we can just choose to ignore the issue. That is exactly what is being done. It doesn't work out any other way. It's a sensible choice to make. I don't necessarily agree with ignoring the problem, but that's a sane approach to do. I just hope people choosing to do it would be more honest about it.But comparing asbestos in ground, and nuclear waste, demonstrates you have no idea whatsoever about even approximate order of magnitudes of the problems. Asbestos occurs naturally, and as long as you don't breath in the dust, it's not toxic in any way.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 01:48:34 pm
content: Quote from: DougSpindler on February 12, 2022, 11:47:36 pmThis is a false dichotomy. We don't need or want either, so it's meaningless to compare which one is "worse" (I would agree with you it's the coal). (We can accept continuing burning small amounts of coal during hard conditions, like very cold winter days where sun does not shine and wind does not blow. All the problems related to burning coal scale approximately linearly, possibly even with some offset making low levels even more acceptable, and coal adjusts to quick load changes way better than nuclear, for example.)

author: nctnico
author_rank: Super Contributor
timestamp: February 13, 2022, 01:52:13 pm
content: Quote from: Siwastaja on February 13, 2022, 01:41:40 pmAnd where do you think Uranium comes from? In the end everything comes from the ground! IIRC there are some places on earth with unhealthy levels of radiation where nuclear fission happens spontaneously (when enough water collects to start & maintain the reaction).BTW: the 100 years comes from the website of the storage facility for nuclear waste in the NL. I like to think they know what they are doing.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 01:54:14 pm
content: Quote from: nctnico on February 13, 2022, 01:52:13 pmI suggest you start by looking up what nuclear reaction means...It'sliterallythe thing that changes atoms into something else, which does not exist in the ground. Uranium isn't the problem!Of course, finally all the electrons, protons and neutrons are "from the ground" but this isn't very helpful way to think about it.You can look up what the products are, and how dangerous they are. Cs-137 alone takes a lot more than 100 years to drop into manageable levels when highly concentrated. 10*half-life would be 300 years. Plutonium is similar. Not that longer-lived components are safe, either.Unused uranium fuel is very benign in comparison, even when it's very concentrated.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 13, 2022, 02:11:39 pm
content: Quote from: Siwastaja on February 13, 2022, 01:39:09 pmNot much is being built because there's not enough incentive to do so. I would expect thermal storage and automated load scheduling to take care of the majority of the problem, with batteries and other electrical storage taking the remainder.Quote from: Siwastaja on February 13, 2022, 01:48:34 pmDon't need that if demand is adapted to supply. Provide incentive for it and it will happen.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 02:28:49 pm
content: So why don’t we use all of the nuclear material from the 100s of thousands of nuclear warheads? Right now we have enough highly enriched nuclear material to supply the world’s electricity needs for 650 years. What else are we going to do with the stuff? Blow each other up? Why not use it?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 13, 2022, 03:10:24 pm
content: Quote from: DougSpindler on February 13, 2022, 02:28:49 pmI doubt that number is right. The warheads may be enough to run 1 nuclear power plant for 650 years - that sounds about right, as they need about 1 ton of fissile material per year. Much of the weapons material is plutonium and not many reactors are made to run on plutonium.

author: dietert1
author_rank: Super Contributor
timestamp: February 13, 2022, 03:42:35 pm
content: We learned above that it's rather the other way round: Nuclear energy projects (fission and fusion) have been and are part of military programs. Especially breeders.Considering the prospect of a new war in Europe next week, with a non-zero chance of nuclear escalation, as we all know, i need to stop here.Regards, Dieter

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 05:57:41 pm
content: Quote from: dietert1 on February 13, 2022, 03:42:35 pmDoes each side really need 70,000 nuclear bombs?Warheads have highly enriched nuclear material, powerplants need only slightly enriched and what's left can be recycled. Do the math.... If the nuclear warheads were used for nuclear power we have well over 500 years of fuel today. What else are we going to do with the stuff?

author: tom66
author_rank: Super Contributor
timestamp: February 13, 2022, 07:25:58 pm
content: Quote from: nctnico on February 11, 2022, 10:11:10 pmDisagree.Li-ion batteries are at $100/kWh.3,000 cycles (easily achievable with NMC with the right additive) = 3.3c/kWh stored and retrieved. That's about the marginal cost of wind in a free market right now but around a fifth that of natural gas.Tesla warrant their 13.5kWh Powerwall at 37.8MWh after 10 years to 80% SoH, which is 2,800 cycles so this is not pie in the sky. It is technology you can buy now.And batteries are getting better every decade, by the time wind power starts exceeding 50% of generation we will have 10,000 cycle batteries.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 13, 2022, 07:53:46 pm
content: Yes, properly designed li-ion systems are already nearly there, approaching price which works out without artificial incentives.It's not the cell cost anymore which is dominating, it's the "overhead" from packaging, thermal management, external (from the cell) safety, power conversion electronics, et al. And there is still room for design optimization since this situation is fairly new; just 10-15 years ago li-ion cells were so damn expensive that everything else did not matter.Yet NiHaoMike has it right that distributed thermal storage and load scheduling has a lot of potential to even out the peaks. This is also existing technology; such thermal storage system was installed in my house in 1982 exactly for the same purpose, to even out consumption by providing lower rates at nighttime. This system was improved by me by installing air-source heat pump last year. This Chinese wonder (rebranded as Swedish "innovation"), which by the way does decent job, already includes control logic for electric utility communicating load scheduling. This is all existing technology. I'm happy to cut all heating for 12 hours with what I happen to have, without special investments. With a bit of planning, i.e., larger reservoir, make it 2-3 days, easily.Hydrogen is not total scam, you just need to understand the limitations and where it applies. In the future, we will have situations of so much excess energy production that all demand is satisfied, and all high-efficiency storage (pumped hydro, li-ion, whatever) is already maxed out. When this happens, havinganyefficiency is better than wasting the production capability. Though, the investment cost can't be high, otherwise it makes no sense. Hydrogen is easy to produce without large investments, but low-cost storage (as is, or converted to some other chemical form) is still challenging.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 13, 2022, 07:59:52 pm
content: Increasing the number of cycles the cells last helps only to a limtied extend. It is rare that the storage would get more than 1 cycle per year. So 1000 cycles is alread some 3 years. In addition to the short time storrage there is also the longer time part, e.g. between summer and winter or at least over the often around 10 days a wether pattern (sunny or cloudy or cold phase) needs to change. So there is also need for storage with a rather limited number of cycles per year. This parts needs a low cost for the capacity and cases less about the efficiency.

author: nctnico
author_rank: Super Contributor
timestamp: February 13, 2022, 08:07:28 pm
content: Quote from: tom66 on February 13, 2022, 07:25:58 pmAt a price where every kWh stored costs you over 21 eurocents. Just look up the price of a Tesla powerwall and do the math. As Siwastaja has written: the price of the cells is just one factor. With small scale storage you pay relatively much for the casing + electronics + installation (which isn't included in the price of Tesla's powerwall BTW).On top of that grid synchronisation will become an issue if small scale storage starts to dominate; that will cost additional money for bringing in time synchronisation over a fiber to every home with small scale storage. I assume you don't want to have the grid synchronisation be depending on something so easely hackable like GNSS or any wireless time transfer mechanism... Grid operators have moved or are moving away from using GNSS for grid synchronisation.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 13, 2022, 08:20:24 pm
content: Quote from: DougSpindler on February 13, 2022, 05:57:41 pmA 1 GW size reactor needs about 1 t of fissile material (usually U235) per year. Usual burnup is around 40 GWd/t with some 3.5 % of enrichment. With recycling the fuel this may be a little less, but not that much difference in the normal light water reactors and reprocessing is a bit controversial.The worlds total plutonium inventories (1/3 of this is weapons grade) is bit over 500 tons.(https://www.recna.nagasaki-u.ac.jp/recna/en-fmdata/pu_2021)Not much highly enrichted uranium is used for weapons.So the total inventory is good for around 600 years to run 1 reactor, not much more.Burning it in reactors would make some sense, but it still needs some work to get reactors certified to run on MOX or similar fuel. Still this would be someting like 30 reactors for 20 years, maybe a few more when only a part can be plutonium. No real need to build new ones for this.

author: tom66
author_rank: Super Contributor
timestamp: February 13, 2022, 09:42:29 pm
content: Quote from: nctnico on February 13, 2022, 08:07:28 pmI'm talking about Tesla's Powerpack solution in grid scale costs at 3.3c/kWh plus overheads. I suspect the overheads in reality for such a solution are small. As it's already being installed by many utilities, I doubt it would be if it truly costs 21c/kWh.I don't think it makes much sense for the home, unless you have huge amounts of home solar or are an early adopter of new tech. There are cheaper batteries than Tesla's but they have worse warranties and integration.BTW, I use the Powerwall warranty because it's publicly available, we don't know what the Powerpack is warranted to, but it stands to reason that the cells would have a similar lifespan. This is also good reason to believe EVs will have good battery lifespans.Quote from: nctnico on February 13, 2022, 08:07:28 pmI really don't think this is as big of a problem as you indicate. I don't know what the long-term guaranteed accuracy of frequency is for any given grid and sure it is used by digital clocks and a few other types of timers, but 0.01% accuracy is probably fine.For instance, nearly every cellular base station has used a Rubidium oscillator in the past to keep time. These manage a few 10's ppb per year and are commercially available.The likelihood is that a grid could manage fine even if it didn't use GNSS synchronisation.And for phase syncronisation, technology already exists, with grid tie inverters synchronising onto the AC feed. The effect is the grid is steered one way or another by these inverters, but you could alternate the phase that each inverter pushes to limit the frequency slip.And of course these issues further go away when you do as much of the grid in HVDC as you can, which is becoming more and more commonplace even for short distance links. For instance a new windfarm is being built off the coast of the UK and it's proposed to use HVDC to link the 15km undersea cable with the mainland.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 10:16:43 pm
content: BATTERIES MAKE NO SENSE, here's why.....I live in California/San Francisco suburbs where our power company/PG&E has scheduled power outage to "protect" us from wild/forest fires. As a result the commissioned solar sales "experts" are selling battery packs to power people's homes during these scheduled outages. After the federal tax credit people are paying $10,000. The solar sales people say the battery pack will power your "home" during an outage.I have 6 neighbors who purchased 1 to 4 battery packs to power their home. (Most spend $20,000 and have two.) Can be Tesla matter if it's a Tesla Powerwall, LG, Enphase etc., pricewise they are all about the same.THE REALITY1 - The battery packs DO NOT power people's homes just part of their home. At the time the packs are installed you have to designate which devices you want powered. That turns out to be about a quarter of your house after the refrigerator.2 - My neighbors tell me one battery will part of their home for about 4 hours. Think about that, $10,000 for 4 hours of electricity to power part of your home. Now when we had a 3 day outage and it was overcast the neighbors who spent $40,000 to power their home were only able to get just about, but not quite 2 days. Yes their solar panels changed their batteries, but it wasn't enough to carry them through a 3 day power outage.No compare that to spending $800 for a gas powered generator which will give you continual power as long as you have gas. And the time to "recharge"/refuel the generator is 15 minutes. Why would anyone spend $40,000 for batteries which might give 2 - days of power and take many hours to recharge depending on the position of the sun when one can spend $1,200 for a generator and gas?If you are talking about Lithium batteries where are you going to get the Lithium? And don't forget there are a lot of environmental and heath issues when it comes to mining for Lithium. In Nevada there's a lot of opposition to prevent mining for Lithium. Where's all of this Lithium going to come from?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 13, 2022, 10:46:25 pm
content: For the short time (e.g. 1-2 cycles per day) the batteries absolutely make sense, as batteries get a good efficiency and very good reaction speed.If it makes sense for local batteries for individual houses is a different thing. In this case it is only to a very small part for backup on a power outage, but for for buffering the PV power and getting more money for the power. How much is paid there is very much a political / regulatory decision and differs between places and often regulations are not really clever or good.The lithium batteries do not actually contain very much lithium - there is more of other materials and the difficult parts may be cobalt and lantanum.Lithium mining in many areas is not that bad as it is salt lakes / near surface salt deposits. If they don't want it in nevada - buy it from China.For the large, utility scale buffering there may be different (hot) battery cells that may be a good alternative if needed. Currently the Li cells are competative and available.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 13, 2022, 11:07:02 pm
content: Quote from: Kleinstein on February 13, 2022, 10:46:25 pmAre you going to pay? Or do you expect families to spend $20,000 to $40,000 or more so they can have some battery supplied electricity? Any idea what the abundance and prices are for cobalt and lanthanum?https://thereaderwiki.com/en/Abundance_of_elements_in_Earth%27s_crustThis might be a language issue, but are you saying we have the technology for large, utility scale buffering with (hot) battery cells? Is this technology we have today? Last I heard there were unsolvable issues with the technology MIT prof came up with.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 13, 2022, 11:36:08 pm
content: Quote from: DougSpindler on February 13, 2022, 10:16:43 pmOne Powerwall is 13.5kWh, 3.3kW of load is a lot more than essentials for most people. Were they thinking they can keep their Bitcoin miners or marijuana growing going for days?QuoteJust one little problem: most gas stations don't work if the grid is down. And generators (even the inverter type) tend to be horribly inefficient at light load and need to be operated regularly so they'll work when needed. The efficiency can be improved considerably by charging batteries so the generator only needs to run intermittently. Delta has a solution that does just that (3.6kWh battery + generator), but for occasional use, a (plug in) hybrid car that doubles as a generator also solves the need for regular testing.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 14, 2022, 04:19:50 am
content: Quote from: NiHaoMike on February 13, 2022, 11:36:08 pmYou are not factoring in the cost of the batteries/powerwalls. AND the fact the power outages are in the summer, typically on very hot days where people need some from of cooling to stay alive. I assure you people will use the generator to keep alive and don't car if they are inefficient.When we have these planned power outages everyone is notified a day or two in advance. Operating gas stations can be found within a 15 minute drive. California has 74 different power companies and PG&E so far is the only one pulling the plug on it's customers. Instead of properly maintaining the transmission lines.It's ironic that PG&E won't provide power to customers, but will give the elderly and people with medical conditions a generator so they will have power.One has to ask why the just don't maintain the transmission lines.There are lot of very good posts, but here, but no one seems to think about the cost and the practicality of the idea.

author: Bud
author_rank: Super Contributor
timestamp: February 14, 2022, 06:00:26 am
content: Quote from: DougSpindler on February 13, 2022, 10:16:43 pmWhat is the rationale for that?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 14, 2022, 08:40:28 am
content: Quote from: DougSpindler on February 13, 2022, 11:07:02 pmThere is limited sense in having individual battery back-up. Local battery buffering may make sense in combination with PV. Than the batteries have to be seen as an investment, paid by the fluctuations in the energy market or part of the PV installation. So not as extra costs to pay but a possible investment.The US grid problem is a different one - they may have to live with slightly higher costs for electricity over there to pay for a more reliable grid. Nuclear power would not solve this but only add higher costs for the production and a small chance for a long term black out if security proplems are found, effecting multiple nuclear power stations of the same type.There are sodium-sulfur batteries around for already quite some time. They were even discussed as a possible use in electric cars before Li batteries became available. It is old technology and not much hyped anymore and they are already used for grid scale buffering, though not very wide spread. The reduced costs of the Li cells have reduced the interrest, but the technology is there and AFAIK they can still be a workable alternative.

author: f4eru
author_rank: Super Contributor
timestamp: February 14, 2022, 11:13:28 am
content: Quote from: DougSpindler on February 13, 2022, 11:07:02 pmYeah, battery backup with 2-4 charge cycles/year make no financial sense whatsoever in a consumer environment (backup to outages). Cobalt is now totally irrelevant to grid storage batteries.Batteries make sense i na grid environment if you can cycle them at multiple times per week. (grid stabilisation, and grid day/night solar comp applications)It needs grid interfacing to decide the feed in/charge times to make those applications.Building them at utility or even grid scale makes the most sense.In a individual home setting, it may be just on the brink of financially viable in a very few countries like germany or perhaps California, because of the high price diferential between the very high consumer price of electricity (tax, mainly), and very low price of solar electricity.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 14, 2022, 11:33:36 pm
content: Quote from: Bud on February 14, 2022, 06:00:26 amThe power company, PG&E, over the past 70 years has failed to maintain the high voltage transmission line in California. With the billions of dollars they saved by not maintaining the transmission lines (trimming trees, replacing weather worn parts) they gave bonuses to senior level management and hefty dividends to stock holders. Over the years trees have grown very close to the transmission lines. When the winds pick up, the tree branches touch the powerlines. When this happens the tree explodes into a fireball starting a fire. The wind, and the remote locations of these transmission lines means the fires go undetected for hours. With climate change, draught, and decades of mismanagement of the forests has resulted in a tremendous amount of fuel. Every year PG&E's powerlines cause around 1,000 wild/forest fires. Every year PG&E is finned millions of dollars and pays the fines. PG&E's has found it's less costly to pay the fines every year than maintaining the powerlines.There is now so much fuel in our forests once these fires get started with with bit of wind they are nearly impossible to put out. In Northern California PG&E's lack of maintenance fires has killed nearly 120 people over the past decade and nearly burned to death an entire school filled with children.PG&E is saying for the "good" of the community they have to shut of power to the San Francisco Bay area to prevent fires. What a spin on the truth. What they really mean is the senior execs don't want to give up their bonuses by maintaining the transmission lines. So they just cut the power to prevent fires.... See what a good company we are? We "care" about our customers.https://youtu.be/stZdaBB3l_khttps://www.youtube.com/watch?v=F3OX1PR2SCM&t=5s&ab_channel=FRONTLINEPBS%7COfficial

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 15, 2022, 01:00:37 am
content: Quote from: DougSpindler on February 14, 2022, 04:19:50 amGood thing hotter days have more sun, solar + thermal storage is the solution.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 02:04:45 am
content: Quote from: NiHaoMike on February 15, 2022, 01:00:37 amHow are you going to run an airconditioner from thermal storage?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 15, 2022, 02:14:44 am
content: Quote from: nctnico on February 15, 2022, 02:04:45 amYou have a small battery to run the pumps and fans. With BLDC motors, just a few tens of watts.Then you use solar during the day to "recharge" the thermal storage.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 02:18:28 am
content: Quote from: NiHaoMike on February 15, 2022, 02:14:44 amIs this what your mom and grandmother ARE using? Or are you just telling other people what they should do?You do know this is NOT an air conditioner, right?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 15, 2022, 02:32:28 am
content: Quote from: DougSpindler on February 15, 2022, 02:18:28 amExplain why not.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 02:38:03 am
content: With an air conditioner the air gets conditioned and cooled. The contraption this guy built is an evaporative cooler which something different.Now that I answered your question, would you answer mine? Is this something your mom and grandmother uses? Or do you just tell other people what the should be doing?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 15, 2022, 03:14:39 am
content: Quote from: DougSpindler on February 15, 2022, 02:38:03 amIt's not an evaporative cooler. It's an ice storage chiller.

author: Cerebus
author_rank: Super Contributor
timestamp: February 15, 2022, 03:20:40 am
content: Quote from: nctnico on February 15, 2022, 02:04:45 amIs it possible to generate electricity (or rotary motion) from a source of heat (thermal storage)?Yes, this is how it's normally done. Normally we use a high \$\Delta t\$ and generate that \$\Delta t\$ by actively heating something (combustion generally) but all that is needed is a \$\Delta t\$ between two environments and choice of a suitable thermal cycle to exploit that (Carnot, Rankine, Stirling, etc.).Is it possible to run air conditioning from a source of electricity (or rotary motion)?Yes, this is how it's normally done.I hope I don't have to point out how the two above add together to form an answer to your question.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 04:27:18 am
content: You do need to explain it. I just don’t see how it is practical.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 15, 2022, 04:57:43 am
content: Pound per pound, making ice stores about the same amount of cooling as charging batteries to run a conventional air conditioner, but the ice is orders of magnitude cheaper. And unlike batteries, there's no inherent wearout mechanism and it's perfectly happy being left at any "state of charge" for indefinite periods.

author: Cerebus
author_rank: Super Contributor
timestamp: February 15, 2022, 05:17:15 am
content: Quote from: DougSpindler on February 15, 2022, 04:27:18 amYou talking to me? I hope not, cause I'd hope that a man who spends as much time as you do commenting on public energy generation doesn't need thermodynamics 101 explained to them what with it being fundamental to the whole field.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 05:19:52 am
content: I just don’t see it being practical.

author: Cerebus
author_rank: Super Contributor
timestamp: February 15, 2022, 05:32:13 am
content: Quote from: DougSpindler on February 15, 2022, 05:19:52 amDoug, if you just post without using quotes nobody can tell what you're replying to. The assumption is that if you don't quote a message you're replying to the message directly above yours. If you are replying to the message above yours, you're not making sense. C'mon, you should have figured out how to use this forum by now.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 05:48:17 am
content: Quote from: Cerebus on February 15, 2022, 05:32:13 amI’ve been too broke to pay attention. Since I was the original poster for this topic I felt it jumped the shark/nuked the fridge when some dummy thinks people will air-condition there home with a block of ice and fan and calls that air conditioning. Which it is not. I think we are just one step away from the ultimate conclusion end which is Godwin’s law.

author: f4eru
author_rank: Super Contributor
timestamp: February 15, 2022, 07:34:59 am
content: Nope. The ultimate conclusion is that the big title of this thread is just baity B.S.QuoteThat is just plain Oxen Excrement.(which is, by the way, an excellent fertilizer)

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 08:02:45 am
content: And what is China doing?

author: f4eru
author_rank: Super Contributor
timestamp: February 15, 2022, 08:26:40 am
content: Research that does not at all replace any single solar panel. In fact, it gobbles up a huge budget, and consumes energy for no practical return.Also, they add 50GW of solar every year.Now approx 300GWAnd today they generate over 2200 TWh/year out of renewables, which is more than the rest of the world, combined.................................

author: Kleinstein
author_rank: Super Contributor
timestamp: February 15, 2022, 08:33:56 am
content: Quote from: DougSpindler on February 15, 2022, 08:02:45 amThey participate in the fusion research - much of this is in colaboration with ITER. Even if they don't succeed in getting fusion working the research money is not completely lost. Participating with a relatively moderate amount of money can be a good investment for China to stay in contact with leading edge technologie.However for there future energy supply they invest more in wind power, PV and hydroelectric and to a small extend also in fission nuclear power, which may also have military background.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 10:59:15 am
content: Quote from: NiHaoMike on February 15, 2022, 03:14:39 amNow try that in a place with >95% humidity in the summerEvaporative coolers are nothing new and they are used extensively in places where the weather is dry and hot but such systems are useless when the humidity is high.Quote from: Cerebus on February 15, 2022, 03:20:40 amI was talking about using something practical. You'd need to have a contraption that can deliver at least 1kW of electrical power to the AC system (that is a small one to cool a few rooms in a home) and work with a temperature difference of 50 degrees C at most (outside temperature at 40 degrees, water temperature might be around 90 degrees). It would surprise me if it turns out it works better & more economic compared to slapping a few solar panels on the roof and run the AC from an inverter. A small battery (like being used on an electric bycicle) would likely suffice as a buffer for this particular application.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 11:19:21 am
content: For cooling, flexible load management is really all that's needed.When the sun is shining and it's hot, PV production is high. Just run the AC with it, in correlation with production. If not enough production to do that, it makes even less sense discussing storing something you don't have. So just keep adding PV production capability!When the sun starts to set and production goes down, the need for cooling also goes down. Not to zero, but it reduces. You might still want to run the AC to prevent high-humidity indoor conditions, but you can do it with any modern inverter heatpump on the lowest possible power setting, keeping comfortable enough. This is also for least audible noise during night.Now for heating, things are different. During heating season, we don't have any mechanism of having a massive free energy source directly correlating with the need of energy. Less sunlight is available in winter, you can't just throw more PV at the problem. Wind power works, but the production is highly variable and does not correlate with the need (or correlates in the negative way; coldest weeks tend to be calm). Thus energy storage (thermal or otherwise) becomes more appealing, but then, long-term storage would be what we really need (months; not days).

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 11:23:03 am
content: Quote from: nctnico on February 15, 2022, 10:59:15 amPlease can you just stop this ugly behavior?What Mike showed us is not evaporative cooler, as he said. If you disagree, please prove him wrong. Calling it evaporative again and again won't help.Evaporative coolers "work" by using water at room temperature, with no other source of energy to cool that water. In Mike's idea, the water is used as a thermal storage medium, it is frozen using refrigeration technology similar to A/C, just the time between consuming the electrical energy and cooling the room is shifted by the storage.You can put the ice cubes or whatever inside plastic bags if you want to stop the small amount of evaporation happening as side effect. Then it definitely becomes a condensing one, i.e., it will make the air dryer like any AC unit.I'm not saying the suggestion is practical or I like it, but if you don't understand it at all, don't comment about it.

author: kjpye
author_rank: Contributor
timestamp: February 15, 2022, 11:28:29 am
content: It's perfectly possible to use stored heat to drive an air-conditioning system. How do you think the old-style kerosene refrigerators used to work, and the camping style three-way refrigerators which use gas as one of the sources?Try searching for "absorption chiller".

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 11:39:38 am
content: Quote from: kjpye on February 15, 2022, 11:28:29 amIt is, but it likely is nonsensical due to poor efficiency: heat to mechanical or heat to electrical conversion is the bottleneck.So just partition the problem the other way: instead of:original energy source -> electricity -> heat -> storage -> electricity/mechanical -> heat,go for:original energy source -> electricity -> heat -> storage -> heat,See? Store as heat, but also use as heat!(It's worth noting "heat" just refers to thermal potential energy here, and this can mean both heating and cooling; just the sign of temperature difference changes, but the amount of energy storage is |dT| * C.)However, an air-source AC unit allows you to store heat (in water as the medium, for example) at high efficiency, and releasing that heat is possible passively, with near-100% efficiency. Though, if you want to keep the storage efficiency good with heat pumps, dT cannot extend far, and this means poor volumetric and gravimetric energy density. Mike's idea is to utilize the massivelatent heatstorage related to the phase change of water, which would theoretically improve the energy density by about 10x, but I see large mechanical challenges with it, as water is known to break structures when freezing.Me? I just like the idea of bruteforcing thermal storage of water, accepting the low energy density. People live sparsely today, but somehow seem to be hesitant on wasting a few % of their square meters/feets on something as important as energy storage. A 2x2x1.5 meter water tank is trivial to construct, inexpensive, and stores 100kWh at dT=15degC. But it needs to be over a strong floor, or basement for example. Gravimetric energy density is close to that of lead-acid batteries, or slightly worse. But simplicity and ease of build of this well-tested solution is priceless.

author: f4eru
author_rank: Super Contributor
timestamp: February 15, 2022, 12:55:06 pm
content: Quote from: Siwastaja on February 15, 2022, 11:39:38 amYep, totally agree.But it would need to be an order of magnitude or two bigger for seasonal storage.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 01:27:05 pm
content: Quote from: f4eru on February 15, 2022, 12:55:06 pmSeasonal storage really benefits from large scale. Assuming spherical (or cubical, good enough) shape (the key it, it scales up in all three dimensions), approaching infinite volume, the ratio between volume and surface area approaches zero (because surface area scales up only quadratically). I.e., at small scale, insulation is critical for long-term storage. At large enough scale, you just dig a hole in ground, or mine the bedrock, and the soil/rock itself acts as an insulator enough. One such project, really large bedrock water storage, is built here in Finland, but got almost no attention at all, everybody's interested about storing heat in sand at ridiculously high temperatures, or some hydrogen BS.I ran some Excel calculations, trying to figure out if it could be scaled for individuals, but it really can't. It needs to be large enough to provide heat for a whole district, at least hundreds of households.1-10 cubic meters of heat storage, OTOH, provides completely different level of demand filtering. It is like those 100uF electrolytic capacitors on the board edge, stabilizing the system against supply impedance. Both consumption, and availability of energy vary massively during a single day, but following different rules. In worst days, consumption and production are in the opposite phase. 24 hours of energy storage provides decoupling to this, and it's sensible to do that with flexible load control. EV charging for example, people are fine as long as the vehicle is fully charged in the morning, leaving room for automation to decide when to charge it. Same works out with heating or cooling, but without any reservoir, you can't cut it for many hours. Relatively small and low-cost storage tanks make that 24-48 hours, easily. For longer than that, the returns are diminishing, and we should go for centralized seasonal storage.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 03:03:55 pm
content: Quote from: f4eru on February 15, 2022, 12:55:06 pmI have one, in the US we call it a swimming pool. On the roof I have solar thermal and solar photo voltaic panels. How does this power or heat my house? Or cool my house in rhe summer tha’s cost effective?

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 03:10:29 pm
content: Quote from: Siwastaja on February 15, 2022, 11:23:03 amI understand it perfectly. More than enough to know it is not a practical solution. Think about heat transfer and surface area. By definition the surface temperature of the ice won't go below 0 degrees so your temperature difference is only a few tens of degrees. You'll need a lot of surface area because the point where adding more airflow is reached very quickly. Just look up a datasheet for a heatsink and take a look at the graph that shows the effect of increasing airflow. Adding things like a plastic bag is going to make the heat transfer even worse.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 03:10:44 pm
content: Quote from: DougSpindler on February 15, 2022, 03:03:55 pm1) Insulate the swimming pool, for example using polyurethane sheet2) Don't forget to cover it, too!3) Get air-to-water heatpump, the larger the better. This can heat up or cool down the water,4) Install PV. If you already have, install more. Can't have too much.5) Create a simple control system that runs the heatpump at the power level no more than your current PV production5b) Additionally, once hourly prices for electricity are forced down your throat, you can also run it when the electricity is at cheapest6) Obviously, during cooling season, cool the water. Target could be set at just above freezing. During heating season, heat up the water, instead.6b) Your solar thermal can obviously directly heat the water, too, but you don't want to do this during cooling season. You need heatpump for that, and it needs electricity.7) Circulate this water in fan coil units to cool or heat your rooms. You might want to do this through a heat exchanger as you can't pressurize the swimming pool, and your distribution system might have iron in it.Not knowing the exact size of your swimming pool, but I would assume it can hold enough thermal energy to last for weeks; if a large one, maybe a month. If in doubt, build a bigger swimming pool!Whether sacrificing the swimming pool for such experiment is worth it, or if the investments ever pay back, is left to the reader to decide. Yet, this all makes more sense thanhydrogen, for example. Properly engineered, it makes a lot of sense, but a ghetto modification of a swimming pool is a different story.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 03:14:32 pm
content: Quote from: nctnico on February 15, 2022, 03:10:29 pmOh, that is all true, I was commenting about you mixing it up with evaporative cooling. But yes, I agree, it's not practical as is. But it's clearly a demonstration of the principle; the plastic bag suggestion is a thought experiment proving it can't be evaporative cooling. More engineering is needed to increase surface area, collect condensation, transferring the ice blocks, etc. I don't like using ice blocks, either; making them and transporting them without bursting anything is difficult. If you can accept the lower energy density of sensible heat only, you can store and transport liquid water using standard steel tanks, pipes and pumps, radiators and fan coil units. All very widely in use, already, in millions and millions of houses.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 03:43:44 pm
content: Quote from: Siwastaja on February 15, 2022, 03:10:44 pmIs this something you have done where you live?Now that you have told me what to do, are you going to pay for it?You are telling people to spend $500,000 for to save about $1,000 in energy costs?In the US we have a saying, "Are you on crack?" Which translates to something like "How fucking stupid is that?" No disrespect intended, but what you are telling other to do is like telling people what a wonderful idea a shovel with a rope handle would be.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 03:51:41 pm
content: Quote from: Siwastaja on February 15, 2022, 03:14:32 pmIn the United State ice harvesting was a big business for decades. Ice would be harvested from lakes and shipped to the big cities where people would buy it and use it for cooling and food storage.There's a reason we don't do that anymore. One is, would you want to lug 50 pounds of ice up several flights of stairs every week to put it in an ice box? They every week you have 50 pounds of water to get rid of.NO THANK YOU. I'll gladly pay the power company $1.00 for electricity to keep my food cold. And I have not meet anyone who is willing to replace their refrigator with an ice box.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 03:53:37 pm
content: Quote from: DougSpindler on February 15, 2022, 03:43:44 pmNo; I haven't needed to, because it already existed, because it's so obvious and trivial. It's well possible your neighbor has it, too, just that you don't have a freaking clue what we are talking about, so you don't know about it.My home was built in 1952. The owners of the time did install thermal heat storage in 1982. Smaller than your swimming pool, but nevertheless, the exact concept I described to you, except with resistive heating instead of heatpumps (converted into heatpump by me last year). It was never used before me, really, but it was still installed, because cost of doing so was negligible. Just some welded steel, a bit of pipe and a few valves. This is normal state of affairs, already in 1980's, for solving the exact same problem we have today: electricity production and consumption are not in sync. In 1980's, you could get electric power cheaper during night due to excess production. So you do see A LOT of these installations, typically between 1.. 5 cubic meters. Obviously, designed to store the heat required just for one day. This concept is perfectly valid today, very cheap, and well tested. It can be extended to maybe up to 10 cubic meters, but not much more at households.Today, the energy market is more complicated: we have hourly prices instead of day-night division, and with distributed household PV, free energy available at some times. This is exactly what I do during spring and fall: run the heatpump during day when I have PV production, and use the energy from the 1982 tank at night.https://en.wikipedia.org/wiki/Hot_water_storage_tankQuoteIt was you who asked about if your swimming pool could be used. Maybe assuming you wanted an actual answer to learn about the concept, was wrong. But since you are just a malicious troll and not a honest person wanting to understand anything, but instead asking questions just to use other's replies against them, I have nothing to discuss with you. Goodbye.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 04:18:01 pm
content: Quote from: Siwastaja on February 15, 2022, 03:53:37 pmBut I assume this is only to provide hot water? In the NL these resistively heated warm water reservoirs used to be quite common (including automatic switches that would turn them on during the night) but nowadays they are rare.

author: Cerebus
author_rank: Super Contributor
timestamp: February 15, 2022, 04:25:40 pm
content: Quote from: nctnico on February 15, 2022, 03:10:29 pmYou clearly don't understand it perfectly. Where do you get this magic ice that won't cool to below 0ºC? It won't go to below 0K, but I'm pretty sure that's not what you meant.Look, ice disobeying the laws of physics! A surface temperature of -18.4ºC!

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 04:28:29 pm
content: Quote from: nctnico on February 15, 2022, 04:18:01 pmOf course cooling was not considered in 1982 in Finland. Probably the idea that someone would retrofit it with a "fridge like machine" exceeding 100% efficiency* and also being able to cool the house would have sounded totally ridiculous. OTOH, at that time, in California it would have been just normal.*) defined practically as a closed system being only the home, not the whole planet. Cooling the planet to heat the house is beneficial, and you don't need to pay for that part!But there is no big fundamental difference. The key differences are:* Pipework should be insulated with vapor proof insulation like Armaflex etc. to avoid condensation* Standard radiators are no good for distribution, because they would condensate on the floors; instead, fan coil units come with condensate trays and drainage.This is all completely off-the-shelf stuff and not expensive at all. Used in all modern large buildings. Not as much at households - yet.From energy storage viewpoint, cooling capacity is smaller because of less available dT before freezing, which could cause a risk of pipe burst. On the other hand, not much dT is available anyway with heatpumps if you don't want to sacrifice the efficiency. This reduces the energy storage capability of the system compared to what it was with resistive heating. Mine is 1.2 cubic meters, and while much better than nothing, I would be happy to take 5 m^3 any day, even if I had to compromise on available room space in the basement.I would be happy to own an unused swimming pool and convert it into some serious energy storage use; it's not a $500k project, but maybe it is a $5-10k project. I'm really not kidding!The problem here is, this is all "too simple to be true", people do not see forest from the trees, instead they look for some UFO solutions, the more challenges, the better.The real solutions are:* PV solar, more and more of it* Heatpumps, heatpumps and more heatpumps!* Just the ages-old power transmission lines, stronger grid* Distributed thermal storage* Load control (heating, EVs)What's best, this is all existing technology.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 04:36:04 pm
content: Quote from: Cerebus on February 15, 2022, 04:25:40 pmThe melting point of ice / water is 0 degrees Celsius (at sea level). The melt water will be at the surface so the surface of the ice you use for cooling won't go below 0 degrees.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 04:38:50 pm
content: Quote from: Cerebus on February 15, 2022, 04:25:40 pm. Though, he'salmostright because most of the energy that can be extracted, will be extracted at 0 degC. Contribution between -18 and 0 is small in comparison. And, energy efficiency of cooling something to -18 instead of, say, -1, drops down because of how heatpumps work.

author: coppice
author_rank: Super Contributor
timestamp: February 15, 2022, 04:51:38 pm
content: Quote from: nctnico on February 15, 2022, 04:36:04 pmWhy do you assume the surface of the ice is wet? If its in an insulated environment it won't be. At least not when it has cooled those insulated surrounding to below zero Celcius.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 04:55:02 pm
content: When cooling, the cold surface will anyway condense water from the air, which, unless we are in a very dry climate, has a dew point usually above 0degC.Doesn't matter whether the surface is aluminium fin, plastic film, or ice cube; if it's below, equal, or slightly above 0degC (but still below the DP), it will be wet from condensate, anyway. This water runs off and is drained - the end result is dehumidification of indoor air. This is the part of air conditioning which makes indoor air more comfortable, even if the temperature is still high. This is specifically why I wanted to make it clear that ice cubes are not evaporative cooling; it's hard to analyze exactly, but with dew point significantly over 0 degC, they still dry out the indoor air, the condensate just mixes with the water coming off the melting ice cubes. This must be drained somewhere, to a closed container, where it does not evaporate - to be refrozen later.If we are in a really dry climate, then evaporative cooling can work, too, but it's a completely different discussion.

author: coppice
author_rank: Super Contributor
timestamp: February 15, 2022, 05:07:20 pm
content: Quote from: Siwastaja on February 15, 2022, 04:55:02 pmArabs have been using evaporative cooling effectively for at least 1000 years. Its doesn't work too well in Mumbai, Hong Kong or Singapore though.

author: TimFox
author_rank: Super Contributor
timestamp: February 15, 2022, 05:10:53 pm
content: Quote from: coppice on February 15, 2022, 05:07:20 pmIn the US, it is very common in the desert southwest. Unheard of here in Chicago.

author: Cerebus
author_rank: Super Contributor
timestamp: February 15, 2022, 05:21:19 pm
content: Quote from: nctnico on February 15, 2022, 04:36:04 pmNo it won't goabovethe triple point of water while there is solid water present, nothing prevents it from beingbelowthe triple point of water. You were just looking at a picture of a thermocouple on the surface of a piece if ice and it was at -18 ºC and you're still prepared to claim that it was at "by definition" at 0ºC and gainsay both the laws of physics and your own eyes. If you don't even understand basic specific and latent heat, how do you expect to understand the thermodynamics of a heating and/or cooling cycle, let alone be in a position to pontificate on them.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 05:28:08 pm
content: The original claim was to cool by blowing air over ice at room temperature. What is going to happen? Given the low thermal conductivity of ice (over 100 times worse than copper) the surface of the ice will melt. Hence the surface will be at 0 degrees.OFcourse you can create very specific situations in which you keep a balance between internal and external heat transfer in order to keep the surface at temperatures below 0 degrees, but that is not the situation at hand.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 05:53:34 pm
content: The surface will be even higher than 0 degC; especially in humid air, it will equal to dew point, because this state change (gas to liquid) requires a lot of energy, regulating the surface temperature. Yes, there are two separate systems with phase changes here, the ice blocks, and the air humidity.But, it's not only the thermal conductivity of ice which limits heat transfer, the solid-to-air contact has probably even worse thermal resistance. Yes, you need surface area to cool the air. This is not difficult to arrange, though; just add the damn surface area until satisfied. Air conditioners use aluminium fins. Mike's ice cube system should just use some kind of "slush", or small ice cubes, maybe with the size of a pea.

author: f4eru
author_rank: Super Contributor
timestamp: February 15, 2022, 06:09:37 pm
content: Quote from: DougSpindler on February 15, 2022, 03:43:44 pmPlease stay respectful.You asked a dumb question in the first place.Using a non insulated swimming pool as a storage basis is obviously not economical.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 06:15:59 pm
content: Quote from: Siwastaja on February 15, 2022, 04:28:29 pmYou'd need to isolate the swimming pool pretty well from the outside to avoid the heat leaking away. Still, if you DIY you can save lots of money. This discussion reminds me: a couple of years ago I investigated into building a 4mx5m-ish basement under my home to get more space. It is definitely something I can't DIY. Having it built would set me back about 200k euro. Making an underground tank in the garden is an option but tricky because it might start to float on ground water.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 06:27:19 pm
content: Quote from: nctnico on February 15, 2022, 06:15:59 pmI tell you what if you think it's a $10,000 project I will fund it. I will even give you double the high end of what you think it would cost, $20,000. I will even pay for your travel and expenses to do it and for your time. But if you are wrong and you are full of shit I would like my $20,000 plus travel, expenses and your time refunded.Do we have deal?

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 06:28:12 pm
content: Very good video from Practical Engineering about the grid.https://youtu.be/KciAzYfXNwU

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 06:32:53 pm
content: Probably easiest would be to insulate the swimming pool from the inside, using insulation material that can take the pressure, for example XPS insulation board, and on top of it, new watertight lining. Quick googling reveals a typical swimming pool could be something like 4 x 8 x 2 m^3.With my magical energy storage Excel:Inputs:* 200mm of XPS insulation (lambda = 0.036 W/mK)* price of said XPS insulation 100EUR per m^3* average ambient temperature +30 degC* storage min +2 degC, storage max +15 degC, storage dT=13 degC* this means, +2degC is considered 100% state-of-charge, +15 is 0%.The results are:* Volume 43.7m^3* Surface area 90.6m^2* Average leakage power (at 50% SoC, at average ambient temperature) = 350W* 100% -> 50% self-discharge in 39 days* Storage capacity 661 kWh* Cost of insulation material: 2240 EURCost of equivalent li-ion battery system at 300EUR/kWh: 198327EUR.To put the 661kWh storage capacity in perspective, if your ambient is at +30 average, in a mid-sized house cooling power of 3kW makes it comfortable enough to live in. Thus, the storage would drain from 100% to 0% in 9 days. Obviously, input power into it must average that 3kW. The leakage power of 350W means roughly tad less than 90% efficiency.The downside is obvious: no swimming anymore. Unless you like it really chilled in summer, and really hot in winter!The elephant in the room is that you must oversize the heatpump because it runs partial duty cycle (whenever that "cheap energy" is available). If you would just heat/cool 24/7, you would use a smaller machine, costing less. Also, more expensive air-to-water type needs to be used instead of the cheap air-to-air room air conditioner type. But of course, for the real DIYer, the latter can be easily modified to cool/heat water.Quote from: DougSpindler on February 15, 2022, 06:27:19 pmNo, and will not have. As I said, I'm not discussing this with you because the communication fails so badly because you don't understand at all what I am telling you, so you are also dissatisfied with my contribution for no reason. It's fine, you don't have to understand. Only you lose.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 15, 2022, 06:39:05 pm
content: Quote from: Siwastaja on February 15, 2022, 06:32:53 pmDo you own a swimming pool? Have you ever built a swimming pool? I don't think so. I own a pool and have built a pool. How are you going to prevent porpoising? You do realize what your saying might work on paper, but that's it.By the way our pool is 25,000 gallons.

author: nctnico
author_rank: Super Contributor
timestamp: February 15, 2022, 06:57:33 pm
content: Quote from: Siwastaja on February 15, 2022, 06:32:53 pmLooks good but I have one question though: is the leakage to ground calculated as the ground being at 30 deg C? AFAIK the ground is usually much cooler. More like 15 degrees C.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 15, 2022, 07:14:23 pm
content: Quote from: nctnico on February 15, 2022, 06:57:33 pmYou are right. Correcting thissignificantlyreduces the heat loss, allowing to change to 100mm XPS instead of 200mm; but maybe the top lid should be thicker.The ground plays in our favor in nearly all cases; during cooling season, it's colder than outside air, and during heating season, it's warmer than outside air (specifically when it matters the most).Needless to say, I'm not seriously suggesting wide scale conversion of swimming pools into energy storage. It obviously requires quite heavy DIY mindset, and not everyone would succeed in it. But, swimming pool has at least one upside: it is already engineered to handle the static pressure of water, and usually well tested in that regard.While we looked at houses we considered buying, a few had indoor swimming pools, in their basements, a stupid trend thing in 1970's. Funnily, no one uses those pools, so it's all wasted space, ready to be converted into something else. It's a cultural thing: we go to sauna and then jump in snow, or frozen lake through a hole made in the ice. No-no to heated swimming pools, too comfy. So, that would be something to be converted into energy storage.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 16, 2022, 12:11:57 pm
content: What exactly was the breakthrough in the BBC report? NIF in the US had the breakthrough first.https://youtu.be/Udukm_OJiMIhttps://youtu.be/-KEwkWjADEAHer’e the real. Breakthrough when it comes to Nuclear Fussion, it’s in the mathhttps://youtu.be/LJ4W1g-6JiY

author: wraper
author_rank: Unknown
timestamp: February 16, 2022, 12:19:51 pm
content: Quote from: DougSpindler on February 16, 2022, 12:11:57 pmQuote

author: DougSpindler
author_rank: Super Contributor
timestamp: February 16, 2022, 12:29:58 pm
content: How is that better than what NIF did?Whers’s the breakthrough?

author: wraper
author_rank: Unknown
timestamp: February 16, 2022, 12:32:41 pm
content: Quote from: DougSpindler on February 16, 2022, 12:29:58 pmQuote

author: DougSpindler
author_rank: Super Contributor
timestamp: February 16, 2022, 12:36:21 pm
content: Who has the better Q? Isn’t that the real breakthrough?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 16, 2022, 12:43:05 pm
content: The next break through needed would be a Q higher than about 10, so enough to actually have a chance to get overall energy out.Another point where they still need a break though is generating enough tritium and finding a wall material that can last longer than 2 years under power generating conditions. These 2 points may be the slightly easier ones, but still not for sure and possible points of failure.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 16, 2022, 03:55:45 pm
content: Which Q number? There are multiple Q numbers.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 18, 2022, 08:10:01 pm
content: Quote from: DougSpindler on February 16, 2022, 12:36:21 pmNot really. The point of Jet is that it is a smaller reactor but can prove things for ITER and future reactors. There is reasonably well understood scaling from increasing the overall size. The advance is that they showed something works more or less as expected and as will be needed for ITER to reach its goals. Same with NIF really. They showed a practical advance in confinment that resulted in an improved Q and power output.Comparing the Q between NIF and JET is pointless, as is looking at the Q of any of these experiments without underlying a good bit of the underlying science and engineering. Even in a far future production fusion power plant Q is only of passing relevance. A $10B power plant that produces 1 GWe with fusion at a Q of 5 is obviously better than one that produces 250 MWe with fusion at a Q of 20. So the absolute power also matters, although without knowing the scale of the equipment behind it is relatively meaningless on its own.Phrasing it as "which one is the real breakthrough" is stupid. It ignores the context entirely, and also neglects the possibility that the answer could be "both" or "neither"

author: dietert1
author_rank: Super Contributor
timestamp: February 18, 2022, 08:31:34 pm
content: To me it seems that efficiency (something like electricity output / total heat produced) will always be less than using sun radiation. There will be additional loss from magnets, lasers etc. on the input side, while on the output side there will be a mixture similar to sun radiation. Anyway, one future problem of this planet will be excess heat, so i don't see how human made fusion reactor will be important.Shouldn't there be projects to build large PV generators in the deserts?There are deserts in the US or am i wrong?Yesterday i found a letter by some congressmen to President Biden, where they complain that the new government tries to protect domestic natural resources while/by concentrating on natural resources of other countries. They lament the domestic jobs lost, but not the cost/risk of military confrontation with other governments.Regards, Dieter

author: nctnico
author_rank: Super Contributor
timestamp: February 18, 2022, 08:57:21 pm
content: Quote from: dietert1 on February 18, 2022, 08:31:34 pmExcess heat is not much of a problem. The amount of heat we generate is neglectible compared to the amount of heat the sun delivers to the earth. IIRC the sun delivers an average of about 160W per square meter over a 24 hour period.QuoteTransport costs, storage costs and political stability (either internal or external; the US still is a collection of seperate countries). Transporting electricity over long distances is very expensive.But there are some ongoing projects using long cables though. IIRC one of the projects is a sea cable between Australia and Singapore to transport solar generated electricity to Singapore. However if you calculate the cost you end up in the US $0.10 per kWh ballpark (IIRC and excluding what Indonesia may charge for having the cable running through their country). Taking into account that this cable is going through a dangerous area (Indonesia has a lot of vulcanic activity), it doesn't seem like a reliable solution.Looking at what is being planned and where technology is heading cost wise, I foresee that in 10 to 20 years from now countries with desserts will become major hydrogen exporters. Australia seems to be in the lead at this moment which is a clever move because they can expect a decline in the amount of coal they export.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 18, 2022, 09:06:30 pm
content: Quote from: dietert1 on February 18, 2022, 08:31:34 pmYes there are desserts in the US as well as in Africa, Middle East, Australia, and Antarctica. One would think it makes total sense to install solar panels in the desert... right? But here's the reality......In the desert their are sunny days with blue sky. The problem is a cloud will form float across the sky and casts a shadow over the solar field for an hour. Output goes from 100% to next substantially less. When this happens the natural gas peaker plants have to be fired up or turned up immediately to prevent brown/blackouts.Second problem - There are massive sand storms in the desert. When this happens solar output greatly decreases of drops to zero. Where's he electrify going to come from?Third problem - The glass, plastic or mirrors used for solar production are caked with sand after a dust storm and have to be cleared. I can share with you pictures of solar panels after one dust storm are producing less than 5% of what they could be producing.Forth Problem - Look at the glass, mirrors or plastic after just one sandstorm the surface is pitted from the sand. The mirrors are no longer reflective and the clear plastic and glass is now frosted.Solve problems 1-4 and the desert wildlife/ecological issues and solar in the desert would work.But in California we have too much solar produced electricity from all of the rooftop solar. There is so much the power company has to pay other companies to get rid of it. So we don't need anymore solar.Here's an interesting fact. All of the rooftop solar in the state of California produces as much power as one nuclear power plant. The solar panels do not produce at night and produce a lot less on cloudy days. A nuclear power plant produces electricity day and night and and cloudy and not cloudy days.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 18, 2022, 10:54:51 pm
content: Quote from: dietert1 on February 18, 2022, 08:31:34 pmYes there should be, and there are. The US brought online over 30 GW of wind and solar last year alone. Depending on capacity factor, that will produce as much (intermittent, sure) electricity as 5-10 nuclear reactors. We are on track to install another 40 GW this year. Another 5-10 reactors. Every projection for rate of growth of renewables made over the last 15 years has been wildly low, but even if we just keep going at the rate we are we will have added the same production capacity as dozens of reactors by 2030. If we start right now we could maybe build some nuclear reactors in that timeframe, but certainly not more than 5 or 10.If we really wanted to, the US could, by 2035, install enough wind and solar to produce as many kWhr as 100% of our current fossil fuel generation, and be well on the way to having 12 hours of grid storage via batteries that are capable of doing daily load shifting. Even at today's prices, this would cost less than the most optimistic cost estimates of nuclear energy. This would not include significant weekly or seasonal storage. But it would could cover a very large fraction of our total electrical needs and probably existing natural gas peaker plants could handle the remaining fraction (at low duty cycle and low carbon emissions) at least until we had a better alternative.It's not like there are no unanswered questions in taking this approach, but it is far more certain than anything involving nuclear power. And if batteries become cheaper (likely to some extent) or off-river pumped hydro takes off or even if fuel cells or flow batteries make sense for longer term storage it only gets better. But even just using proven, commercially deployed technology at today's prices is already good enough to eliminate most of our fossil fuel use in the electricity sector.To be clear, I still think we should be investing in nuclear. We might get to 2030 and find that we can't really get to 100% renewables with practical storage options, or that that it requires too much long distance power transmission and that 20-30% base load capacity from nuclear is really helpful. If so, we are going to be super happy if even a handful of nuclear reactors are nearing completion. But that is the backup plan, not plan A at this point.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 01:24:11 am
content: Quote from: ejeffrey on February 18, 2022, 10:54:51 pmYes if we really wanted to, the US could, by 2035, install enough wind and solar to produce as many kWhr as 100% of our current fossil fuel generation. But here's the trade off. That would require all of the concrete, steel and aluminum produced in the country for the next 12 years. Not building any new buildings, roads, cars, TV dinners for the next twelve years is going to be a hard sell to the world.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 02:08:28 am
content: Quote from: DougSpindler on February 18, 2022, 09:06:30 pmPass that on to other customers, giving them "free" or very cheap electricity when there's a surplus. Allow anyone to take advantage of that, including those who don't have their own solar. They'll figure out some way to use it, be it mining Bitcoins, growing marijuana (where it's legal), making ice or hot water for HVAC, or even just simple stuff like having the dishwasher automatically run to take advantage.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 02:37:49 am
content: Quote from: NiHaoMike on February 19, 2022, 02:08:28 amNice thought, but the world/supply chain doesn't work that way. Just like potatoes this year, 1.5 million pounds are being thrown away. And potatoes can be stored much longer the electricity can.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 04:25:59 am
content: The real problem is that they don't want to do it because in their view, customer owned solar is a step towards independence from the service they're selling and therefore they'll only do things to support it if there's a very strong reason to.Much like how smartphones with long range P2P aren't popular with the carriers since that competes with the service they're selling.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 08:47:34 am
content: Quote from: NiHaoMike on February 19, 2022, 04:25:59 amSolar independence in California is NOT financially feasible for most homeowners in the state of California. Cost for an average home owner is close to $100,000. And starting on August 1st of 2022, PG&E will begin dropping rates for solar customers which will make solar produced power more costly than buying electricity direct from PG&E during solar producing hours.For all of those grid tied customers who were told the solar panels would produce all of the electricity they use will start getting (at least in my case), about a $1,000 per year bill. It’s a pretty slick trick what PG&E is doing. And just wait, the other power companies are about to do the same.Anyone in California would be a financial fool to install residential solar today.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 19, 2022, 08:56:48 am
content: Quote from: DougSpindler on February 19, 2022, 01:24:11 amI somewhat doubt that number - most of the PV panels are imports from China and thus don't need materials from the US, though they still need some for the frames.The US steel production is marginal anyway. Not building new roads is actually a good idea - they struggle to keep the existing roads from crumbling and with ever increasing prices for oil the demand is more like going down.An important point for the US is also to reduce the energy consumption - in many cases it is cheaper to save on the comsumption than to produce even more.It takes quite some effort and investments to rebuild the energy production. The problem with nuclear is that it would need even more material to build up the same capacity. With the large steel parts for the existing designs this would be way higher than the available capacitiy. New designs may be ready from 2040 on and would still need a comparable (or larger) amount of steel. The available cnventional fuel would not last long. So nuclear is not a viable alternative. At best one could argue to slow down the decline somewhat. Current build capacity is hardly keeping up to replace those old plants that are reaching there end of life. So there is little reason to spend money on a non competative technology. The main potential of nuclear power is the potential for a major desaster, but not a chance to solve the energy proplems.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 09:44:32 am
content: Quote from: Kleinstein on February 19, 2022, 08:56:48 amI’m in California and roof top solar is producing too much solar electricity during the day. We have too much and now buyers or way to store it. Then at night, we have too little. More solar is not the answer. Neither is wind. All of the roof top solar produced in our state is the equal to the amount of electricity produced by one of our states nuclear power plants. And unlike solar and wind produces electricity 24 hours a day. And with all of those decommissioned nuclear warheads we have enough fuel for the next 650 years.Nuclear energy causing a major disaster? Yes there have been two. But compare that with oil spills. Natural gas leaks. The massive destruction caused by mining for coal and the ecological disasters coal mining has caused. And what about the thousands of out of control coal mine fires which have been burning out of control for decades. Care to talk about all of the deaths and air pollution illnesses caused by coal, fossil fuel, solar and wind?Nuclear energy has proven to be far safer and less deadly and less environmentally destructive than any other electricity producing method. Yes we have two radioactive hot zones, but compare that to the destruction caused mining for coal and oil and that’s not including spills an leaks.Heck just one small scale coal mining accident is more deadly than all nuclear accidents. There have been more deaths caused by wind an solar then all nuclear accidents. Why would you not be in favor of nuclear when it has such a good track record when compared to all other energy production methods?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 19, 2022, 11:11:55 am
content: If there is excess power on sunny days the problem is not too much PV, but to little storage and to weak a grid. They still have peaks in the power consumption and sometimes rolling blackouts on hot days.Quote from: DougSpindler on February 19, 2022, 09:44:32 amIt comes too late - we would still need PV/wind before nuclear would be ready.The fuel is limited when used in large scale. So nuclear could only be a small contribution (like 10%).The potential for large accidents is still there. So far the accidents in Fukushima and Chernobyl where still with relatively favorable wether conditions / relatively low population density. It could have been a lot worse with a different wind direction. The numbers in the comparison look biased (include older accidents from hydroelectric, but not the early days uranium mining deaths) and can change in the future with the full life cycle.Despite the relatively low risk, there is still no ensurance against large accidents.100% nuclear would still need daily cylce storage, as there would be too much power at night and too little at noon.It is too expensive.Limited scale nuclear can still make sense - that is keeping those plants running that are already build and in good shape. Quite a few older reactors however have reached the safe end of life and upgrades may not be possible (e.g. reactors in Belgium with cracks in the pressure vessel) or too expensive to be econimical.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 19, 2022, 11:54:00 am
content: Quote from: Kleinstein on February 19, 2022, 11:11:55 amOr, there is no problem at all. "Excess solar production" just means part of this free resource is left unused. If you don't have use for it, just don't use it. (Or, you can come up withanyuse, however inefficient).What happens if you have fewer panels?Exact same result - you leave sunlight unused.99.9999% of it is unused anyway!Even if some peaks cannot be fully utilized, that is not a reason not to install more solar. I have 3kW of solar and I seriously consider adding more,notto sell it to grid with crappy price during summer, but to get more than 500-1000W out of it during spring and fall when I actually do need that energy myself!The only actual part of "problem" is, it makes the payback for the panels harder. But handwaving ("boohoo, there's aproblem") is not helpful, it needs to be calculated. It's just a fact that with increased solar, the day comes (and thanks to bad grid, somewhere it is already locally visible) that you can't calculate the investment by assuming 100% utilization for the produced energy. On the other hand, as cheap fossil sources are being driven down, it also means electricity is more expensive when it's most scarce. In the end, the investment plays out.Besides, bad grid can be fixed. This isn't stressed enough. It isn't even expensive. I'm always intrigued by the fact that electricity is easily transported for maybe ~1000km with excellent efficiency, no one blinks an eye, no one eventhinksabout it; has worked this way for decades and decades. A little bit of steel, aluminum and copper is involved.Yet, if someone suggests, hey, make that 1000km into 3000km, the instant reaction is: totally infeasible, can't do, massively expensive, come up with some completely unproven UFO technology instead.Most of the Europe has pretty much functional high voltage distribution, for example. The fact US grid partially looks like it's been bombed down is maybe funny, but not a technical problem; it's a political problem.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 02:10:33 pm
content: Quote from: DougSpindler on February 19, 2022, 08:47:34 amMake that cheap rate available to all customers and problem solved. But then even those without their own solar would be in support for rooftop solar which goes against what the company wants.Quote from: DougSpindler on February 19, 2022, 09:44:32 amNot enough buyers probably because it's priced too high? See above for why they don't want to solve it.Quote from: Siwastaja on February 19, 2022, 11:54:00 amI named quite a few ways to use excess solar. Thermal storage is my favorite since it's quite economical and useful any place that has significant HVAC demand. But of what I listed, crypto mining would probably be the easiest to set up - just plug it in and program it to run only when there's excess production.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 04:48:11 pm
content: Not sure if everyone is aware but there are five power grids in North America.https://en.wikipedia.org/wiki/North_American_power_transmission_gridEach powered has multiple power companies. I know California has about 75 different power companies, but the grid has many more.The electricity we consume in The San Francisco Bay are can come from Washington state or New Mexico where they have coal fired power plants. We are an environmental friendly state so we we burn the coal many states away so the pollution doesn’t affect us.I like many Californians have roof top solar and the power company I am forced to deal with is PG&E. PG&E not only sells electricity, it produces it and transmits the power across the region. Some power companies do all three while others just provide power to customers buying it from the grid.I have seen a lot of posts about how we could store excess electricity, and we are already doing that with pumped storage.You are all throwing out possible solutions but not really thinking through them to see if they would actually,work for us.Wind solar and as we have seen in California with the drought hydroelectric can’t be relied on. One of the hydroelectric plants was off line for months from lack of water.We need a reliable source of power and as many avid anti-nuclear protesters are seeing it current nuclear technology is the way to go with the potential for nuclear fussion to be the ultimate solution.. and I have to agree. As a side note, anyone else notice all of the talk about sodium salt reactors has completely disappeared? So has all the talk about solar roadways. Both sound like good ideas and might look good on paper, but then there’s reality.Can someone please explain to me how thermal storage would work for the grid? It seems to me it’s a dump of an idea as the idiots who want to do gravity block storage. Please tell me why it’s not as clever yet dumb of an idea as a shovel with a rope handle.

author: TimFox
author_rank: Super Contributor
timestamp: February 19, 2022, 04:55:52 pm
content: In the continental US ("lower 48"), there are three major grids: Eastern, Western, and Texas. The vulnerability of shorter-distance grids (determined by politics, not engineering) to relatively local problems was clearly evident in the previous "100-year" cold snap in Texas, about 10 years after the previous one. With such a huge country (area), spreading out the risks geographically is generally a good idea.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 04:59:21 pm
content: Quote from: DougSpindler on February 19, 2022, 04:48:11 pmMake hot water or ice when there's excess energy, in order to use it for heating or cooling when there's less energy available. It would only be effective where there's significant HVAC demand, which turns out to be most places in the US.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 05:16:10 pm
content: Quote from: TimFox on February 19, 2022, 04:55:52 pmI would agree. We've seen many times where an entire grid can be taken down by a series of events. Better a portion that the entire country or continent.

author: dietert1
author_rank: Super Contributor
timestamp: February 19, 2022, 05:21:34 pm
content: Near the place where i grew up there is a gravity storage (Koepchenwerk), an artificial lake about 160 m above a river. Built in 1930 it has 4 tubes of about 2 m diameter to pump up water with excess energy and to let it fall down when electricity is in demand. Maximum input is 20 MW, maximum output 153 MW after 70 seconds.Something similar exists near the place we are living now (Rudolf-Fettweis-Werk). Except this time the level difference is 300 m and the lake is much larger.Regards, Dieter

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 05:28:26 pm
content: Quote from: NiHaoMike on February 19, 2022, 04:59:21 pmSo you want us to make hot water in the desert where the temperature is already 125F/51C? And you want us to make ice when the temperature outside is 25F/-4.And then what?

author: Siwastaja
author_rank: Super Contributor
timestamp: February 19, 2022, 05:47:13 pm
content: Quote from: NiHaoMike on February 19, 2022, 04:59:21 pmThis sounds so obvious but because apparently not everybody here get it, let's make it super clear:The idea isnotto convert stored heat back to electricity; it is possible, but efficiency sucks (also investment cost).The idea is tousethat stored heat, as heat. Whenever stored heat is available, it can be usedinstead ofconsuming energy from the grid and convert it to heat. This can't bring consumption to zero, because we need energy for other purposes than heat, too; for example, watching TV or charging EVs. But heat is a pretty significant part.And in case this isn't clear:cooling is also heat! Heat is a short-hand physical name for thermal energy. Yes: most of our household energy need is in thermal energy, either heating or cooling! Just the sign of temperature difference is the opposite. It should be pretty obvious that if you expect that you needcoolinglater, then you store energy bycoolingthe storage; and if you expect you needheating, then you store energy byheating upthe storage. As a result, there are short seasons when you don't need either cooling or heating, or can't predict which one you need the next day or week. But these seasons are not problematic anyway: energy consumption is low however.Storage tank is thermally insulated so that it keeps the energy instead of self-discharging too rapidly. This should be quite obvious, too, but saying it just in case.Domestic hot water (that you use to shower, for example), is needed during all times. So you may want to store heat also during cooling season. This needs a separate tank. Conceptually, it usually exists anyway. Just make it larger.Personally, I do only positive dT storage, because my distribution system is not up to cooling (not protected against condensation). But here this is fine, cooling needs for summertime are fairly small so can be ignored from energy storage plans.This reply is not for DougSpindler and I am not reading his replies, so no need to waste time playing more games with me. I write this for information for everybody who's interested, because I don't let internet terrorists shut me down; this matter is way too important. I would really like to see more thermal energy storage in use, and I am seriously planning extending my system because what I already have demonstrably works.The key components I see in reducing CO2 footprint and improving sustainability while keeping somewhat acceptable energy cost and self sustainability, are:* Improvement of the grid* Heat pumps (distributed, at households)* Distributed (household) thermal energy storage* PVAll existing and pretty low cost technology. PV is the newest and "fanciest" in the group, but it's becoming cheap and simple, too.But getting there is not without troubles. If more people switch to heat pumps from distributed fossil burning, even though the total energy consumption goes down, the need for electricity production goes up. It's still sustainable because it goes up far less than the energy consumption at households went down! But still, it's a challenge.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 19, 2022, 06:04:42 pm
content: Attached: pictures of my thermal storage system, and the heat pump magically* taking x W out of solar panels (or obviously, grid when I don't have enough production), and producing 3*x W into the energy storage tank, which can be then distributed to the house during the night. This is energy storage.*) not really; scientifically, actually.The storage tank was installed in 1982, not expecting such use case. It probably didn't cost pretty much anything at all, but it seems today welding some steel together seems like an impossible task.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 06:22:37 pm
content: Quote from: Siwastaja on February 19, 2022, 06:04:42 pmIt might work for you, but not for folks in California and most of the rest of the world. Look like you have a leak, is that what the bowl is for? Why don't you get it fixed?

author: nctnico
author_rank: Super Contributor
timestamp: February 19, 2022, 06:38:34 pm
content: Quote from: Siwastaja on February 19, 2022, 05:47:13 pmI wonder about affordability & maintainability of your thermal storage system. How much would a commercial installation cost today? What are the maintenance costs? And ask yourself honestly: if you are going to sell your home, who is going to maintain that heat storage installation?One of the problems that comes with energy transition is that a lot of people can't afford investing into solar and storage solutions; that is typically where the power companies come in which can do investments with a >20 year payback /ROI.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 06:46:16 pm
content: In the US, specifically California, PG&E starting in August 2022 is decreasing the rate/cost electricity during solar production hours. Right now summer peak is $0.58 kWhr. In August 2022 that will drop to $0.15 kWhr. At $0.58 Kwhr for solar payback for my solar system was 4.75 years. With the August rate decrease payback is going to be 60 to 75 years if not more.You would be a fool to install solar today if you are a PG&E customer.

author: Marco
author_rank: Super Contributor
timestamp: February 19, 2022, 07:06:30 pm
content: Rich people can put hydronic air handlers and a buffer tank in their new mansions and save a few bucks at least, for a new install that's a low cost adaptation to the new pricing regime.

author: wraper
author_rank: Unknown
timestamp: February 19, 2022, 07:29:59 pm
content: Quote from: DougSpindler on February 19, 2022, 06:46:16 pmI don't see how 3.86 times price decrease results in 12.5+ times higher payback time when there is no operating cost. Not to say $0.58 kWhr is simply ridiculous and $0.15 kWhr is reasonable but still not cheap.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 07:41:45 pm
content: Quote from: Marco on February 19, 2022, 07:06:30 pmIf you have a mansion in California you have the money to pay whatever the cost would be to heat your house and for electricity. It's far less than a Tesla Mod X car payment so who cares.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 07:52:23 pm
content: Quote from: nctnico on February 19, 2022, 06:38:34 pmA lot of commercial buildings use water based HVAC so adding thermal storage would be easier than for most residential. (In the US, residential water based heating is used in some areas while residential air conditioning chillers are almost unheard of.) It used to be that preventing corrosion was a major problem for water based HVAC systems, but now with PEX plumbing, the problem is reduced to the heat exchangers which are typically copper or aluminum and thus not difficult to make reliable.In any case, it would be vastly cheaper than batteries, with the limitation that it's only useful for HVAC.QuoteSome are investing in batteries for energy storage, granted that also acts as backup power so not a 100% fair comparison to thermal storage. But the point still stands that in areas with significant HVAC use, thermal storage would be far more economical than batteries.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 19, 2022, 07:58:03 pm
content: Quote from: nctnico on February 19, 2022, 06:38:34 pmSometimes I think this forum must be some kind of practical joke.I posted a picture of a totally normal hydronic system. Hundreds of millions of these exists. The technology dates back to 1800's. Mine is build somewhere in 1950's-1960's I guess, and upgraded with a new boiler and that energy storage tank in 1982. Piping, radiators, storage tanks are well known to last for at least 100 years. Those parts I opened for modification were all in pristine condition. So I just reused old iron pipes and fittings and did modifications with hemp and paste like originally. I expect them to be in good condition still in 2100. Rest of the house probably isn't. Expansion tanks, circulation pumps and possibly some ball valves require replacing every 20-40 years, though.Heat pumps also won't last much beyond 15 years. Planning to replace it every 10 years is highly recommendable (i.e., don't pay 10000EUR for 1-day install job, it will waste any savings you get).This is all normal, you don't have any maintenance-free heating/cooling system in existence. A storage tank does not affect this. IMHO, it just should be installed, as large as possible. It's a tiny cost compared to the total. But yeah, you have to pay some 3000EUR for a newly manufactured 3m^3 energy storage tank today, so it's not free, but nothing is when you build new from scratch. It's still like 100kWh of energy storage! Compare this to the cost of li-ion battery storage.But now the opposite is happening; working storage tanks are being dismantled as we speak. I opted not to do that, but instead put it in use.It all boils down to a tiny piece of control electronics and software that is missing: read out PV production, energy spot price, etc. Control heat pump power setting. Adjust motorized mixing valves (yes, these date back to 1970's or so, too) to control energy storage. Currently such control box does not seem to exist. I'm working on it, and it can't be that I'm the only one.

author: nctnico
author_rank: Super Contributor
timestamp: February 19, 2022, 08:07:24 pm
content: Quote from: Siwastaja on February 19, 2022, 07:58:03 pmEmphasis mine: that is the problem right there in bold. You think that this is easy but how is a regular plumber going to figure out where the problem is? You took a bunch of standard components but added a proprietary solution on top of it that makes it unmaintainable for a regular plumber.Don't get me wrong here, I have similar pieces of electronics in my home that sit on top of bog standard heating components but I do realise that when I'm away or after I have sold my home, nobody else can maintain these and they likely will be replaced as a result if problems occur.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 08:13:50 pm
content: Quote from: wraper on February 19, 2022, 07:29:59 pmThat is exactly what the power companies PG&E and the others who will be doing the same want you to think. This is part of the doubt and confusion campaign.When you install solar you are placed on a Time of Use Plan. For the rate plan I am there are 6 different prices the power companies sell me power at and six different prices I sell excess power to the power for. In one day the cost for a kWhr changed 5 times. What the power companies are doing is changing the cost they are selling and buy electricity for but they are also changing times they are paying those prices.Right now PG&E will charge me $0.58 Kwhr to consume. If my panels are over producing they will pay me $0.56 kWhr. Later today when I charge my car when the rate is $0.15 kWhr I can spend the "money" I "earned" from selling the electricity to PG&E. For every 1 kWhr I over produced and sold to PG&E I can get 3.73 back when the rates are at $0.15. With the sell one, get 3.73 back the our solar panels paid for themselves just under 5 years. What a deal!But PG&E is dropping prices.... Sounds good doesn't it. Lower prices.... Who doesn't like lower prices?At the same time they changed the times for peak, partial-peak and off peak hours. There is no peak or partial-peak during solar production hours any more. PG&E is not paying a flat $0.15 for excess solar.So now when I have 1 excess kWhr to sell to PG&E I get $0.15 as a credit. But when I need to buy that 1 kWhr back when PG&E is charging $0.58 I have to pay out of my pocket $0.43. So to offset the price difference I now need to install 3-4 times as many solar panels as I currently have.PG&E's TOU pricing is much more complicated. But using my data for the past 5 years, I have been over producing $1,100 every years. At the end of the year, PG&E gets this $1,100 for "free". When the rates change in August I will have to pay an additional $800 out of my pocket in addition to the $1,100 I'm already giving to PG&E.SOLAR MAKES NO FINANCIAL SENSE FOR PG&E CUSTOMERS ANY MORE. There new low price of a kWhr of electricity is lower than the what one can produce a kWhr with roof top solar.Get it?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 08:32:03 pm
content: Quote from: nctnico on February 19, 2022, 08:07:24 pmDocumentation is everything. It should clearly explain how the system works and what the signals should look like. Much easier said than done, the main barrier to get past is the impression that good documentation is of little value on a system that has already been built.In the end, it's really no different than a home network or home theater system. In particular, older home theater systems needed the user to understand how everything is connected.Quote from: DougSpindler on February 19, 2022, 08:13:50 pmOr use the solar as it's being produced so you don't have to buy as much on peak. That can be done with thermal storage if HVAC is most of that use.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 08:51:49 pm
content: Quote from: NiHaoMike on February 19, 2022, 08:32:03 pmWe don't have an HVAC system as do most of the people who live around use. Looking at the cities to the west of us, well over a million people, none of them have HAVC systems either. It's just not needed.

author: nctnico
author_rank: Super Contributor
timestamp: February 19, 2022, 09:04:22 pm
content: Quote from: NiHaoMike on February 19, 2022, 08:32:03 pmNot just that but also support is needed. The average plumber that works on heating systems knows jack sh!t about how a heating system actually works. No idea. They just connect the pipes & wires as they have learned during their training. Doesn't matter if it makes sense or not (don't get me started...). Even with documentation, they have no idea what to do with a homebrew system. Their skill level just doesn't go that far. If they can't call a manufacturer for support, they are clueless about what to do.Bottom line: if you can built your DIY thermal storage system; great! But it will take much more to make it a scalable solution that can be installed widely. Maybe millions of systems already exist in a country that can 'easely' be converted but it has to make sense financially to convert these systems. There are so many things to figure out before you could even market such a solution.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 09:21:50 pm
content: Quote from: DougSpindler on February 19, 2022, 08:51:49 pmThen what is the peak time use?Quote from: nctnico on February 19, 2022, 09:04:22 pmIn the US, service techs for air conditioning, heat pumps, and refrigeration do need to know how those systems work. It's required to get the EPA 608 license.

author: Someone
author_rank: Super Contributor
timestamp: February 19, 2022, 11:02:26 pm
content: Quote from: Siwastaja on February 19, 2022, 07:58:03 pmDespite already being built into inverters, that sort ofcomplexitytrivial control spawned a (rather expensive) box to make it palatable to dumb installers/consumers:https://www.fronius.com/en/solar-energy/installers-partners/products-solutions/residential-energy-solutions/ohmpilot-hot-water-with-solar-powerElectricians familiar with industrial control, just added a timed relay to the inverters GPIO.Wedontshouldn't need another layer of complexity with an intermediate product to orchestrate all this! Appliances with a demand control input (shift set point when commanded) could do it directly.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 19, 2022, 11:15:51 pm
content: Quote from: Someone on February 19, 2022, 11:02:26 pmThat's a thyristor phase angle controller to modulate a resistive heater to exactly match the surplus solar production. Basically a very high power light dimmer with a controller that tries to minimize import or export.

author: Someone
author_rank: Super Contributor
timestamp: February 19, 2022, 11:37:59 pm
content: Quote from: NiHaoMike on February 19, 2022, 11:15:51 pmYes, do the maths on its payback period compared to alternatives (including alternative of do nothing) and consider if it makes sense in your circumstances.But the OP said there were zero products for self consumption regulation/control.... yet there are several, for different end loads, to the point of having such a specialised device available off the shelf.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 19, 2022, 11:41:36 pm
content: SOLAR MAKES NO FINANCIAL SENSE FOR PG&E CUSTOMERS ANY MORE. AND IT"S GETTING WORSE.I just looked today and the rate PG&E is now paying and has been paying for excess solar is $0.58 kWhr. When I last looked PG&E was going to pay $0.15 for over produced solar. Out of curiosity I just looked and PG&E as of August 1st, 2022 will only be paying $0.10. Yes they are lowering rates, but at the same time it's going to take customers with residential solar 3 times longer before they can break even. In my previous post it was looking like 60 years. Now it's looking more like it will be 100 years.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 20, 2022, 12:07:08 am
content: There are solar setups that break even in a reasonable time at $0.10/kWh. Perhaps the answer is to DIY so that you don't end up paying the ripoff installers.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 12:12:28 am
content: Quote from: NiHaoMike on February 20, 2022, 12:07:08 amAt $0.10 kWhr I think it's highly debatable for DYI.

author: Someone
author_rank: Super Contributor
timestamp: February 20, 2022, 12:50:34 am
content: Quote from: NiHaoMike on February 20, 2022, 12:07:08 amEven at 10c/kWh in Australian dollars and at the bottom of the Australian mainland (38 degrees south) , there are commercially installed residential systems with payback periods in the 6-8 year range. Its like certain noisy people who say how cheap their Tesla car is without explaining the myriad of subsidies/incentives they received, all this is so specific to the location and the payments/rates available.If you take some random datapoint (no idea if trustworthy):https://www.energysage.com/local-data/solar-panel-cost/ca/That would suggest a solar system in California US is still very viable, its not like this is hard to check:https://pvwatts.nrel.gov/index.php12 year paybackSo... please stop feeding the toll!

author: nctnico
author_rank: Super Contributor
timestamp: February 20, 2022, 01:46:17 am
content: Quote from: NiHaoMike on February 20, 2022, 12:07:08 amIf you manage to buy used solar panels and an inverter cheaply and climb on the roof yourself, yes then it is doable. I have looked into this myself (aiming for a 4 year payback) but I couldn't get the deal closed for the solar panels and have not revisited the idea since. Buying new panels and having it installed just fills the pockets of the installers; they are the only ones making real money from the solar panels. Like people who sell mining equipment say: mine the miners! On top of that there is no subsidy possible if you install the panels yourselfAnother example are green roofs. You can get subsidies for that as well over here. Because our shed got a new roof recently, I looked into putting a plant based (green) roof on it. Prices are insane!

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 02:46:58 am
content: Quote from: Someone on February 20, 2022, 12:50:34 amDown under do you have TOU rate plans where you pay a different amount based on the time of day or do you have a flat rate. In the US/PG&E the amount we pay or get credited for excess solar changes 5 times in one day. In one day we are paying anywhere between $0.15 kWhr to $0.58. In addition to variable pricing during the day we have a tiered system on top of that. If you use more than your base allotment the rates increase. Depending on the TOU rate plan there can be 3 tiers.Not sure why you are referring me to PV Watts as it will NOT work for PG&E customers. By default you MUST enter in the average cost for a hWhr. Problem with that is the accuracy is plus or minus 250%. It's useless for PG&E customers. Now you can dig deeper in the program and enter some TOU data but it's not enough to get anything that's close to being accurate.In the US PG&E is leading the way in sliding scale pricing for residential customers. PG&E has 14 different rate plans for residential customers. When you become a customer of PG&E or install solar you must select 1 of the 14 rate plans. Imagine going to the gas station to buy a gallon of gas. Depending on what day of the week it is, time of day, and how much fuel you have purchased so far this month that determines how much you pay. This means you could be paying $0.58 kWhr at the pump you are getting gas from and I could be paying $0.10.Can you name one other product when two people are buying it at the same moment in time from the same company there is nearly a 600% difference in the price?Forgive me, but your estimate of 13 years payback is just laughable for PG&E customers one rate for solar production hours drops from $0.56 to $0.10. During non-solar production hours customers even with solar still have to pay $0.58 kWhr.Frankly I don't see how any PG&E customer will ever be able to breakeven by installing solar. Again, I'm ONLY talking about PG&E customers.If you think I am wrong, please take me through the calculations. What PG&E is doing is very clever and will screw every PG&E customer who has or is going to install solar.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 20, 2022, 03:47:05 am
content: Quote from: DougSpindler on February 20, 2022, 02:46:58 amIf solar can break even against $0.15/kWh flat rate in a reasonable time, it will break even sooner on a variable rate that sometimes is higher. And it can offset enough use to not go into the higher tiers.The installers overpricing systems based on past rates that still allowed overpriced systems to pay back quickly is a different problem.

author: Someone
author_rank: Super Contributor
timestamp: February 20, 2022, 03:47:31 am
content: Quote from: DougSpindler on February 20, 2022, 02:46:58 amYou sir are an idiot, a loud and dithering one at that. Size a solar system, price it up with those exampleaveragecosts, then....using the worst case 10c/kWh pricing... it still ends up being profitable.So what are you saying? You have some special maths or some unrealistic cost point for a solar install?Your sideways discussion for no point won't work here, either put up some specifics/justifications or expect forceful pushback of your nonsense.

author: Someone
author_rank: Super Contributor
timestamp: February 20, 2022, 03:49:36 am
content: Quote from: NiHaoMike on February 20, 2022, 03:47:05 amIndded it seems to be a big wall of text claiming they can get paid at least 10c/kWh and often more, yet somehow that situation is less profitable than someone always getting 10c/kWh.newmaths!

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 04:25:10 am
content: Quote from: Someone on February 20, 2022, 03:47:31 amDude you are not getting it or are you just daft? The solar sales crooks use the average price and every grossly oversell to the tune of $10,000 to $15,000 more than what one has to pay if they did it your way. I received five separate quotes for solar panels for my home. Prices ranged from $27,000 to $40,000 to produce enough electricity to cover 100% of my yearly usage. But then I talked to an installer who understands PG&E rate plans and he sold me a system that was half the size and said even that would be too big. I spent $14,000 and they sales guy was correct it was too big. Every year I have over $1,000 of electricity I don't use and have to give to the power company for free. I probably only needed a $10,000 system.To be fair to the solar estimators each one of them was corrects in sizing solar for my home. The difference is they all used different PG&E rate plans. If I used the average rate as you are suggesting I would have overpaid $23,000. Why would you tell people to spend $23,000 more than they have to?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 20, 2022, 05:06:15 am
content: Quote from: DougSpindler on February 20, 2022, 04:25:10 amSo find ways to use the extra electricity? Perhaps get an "outdated" Bitcoin miner for cheap.Going DIY fixes the installer problem altogether and also allows starting small and building up over time.

author: Someone
author_rank: Super Contributor
timestamp: February 20, 2022, 05:44:21 am
content: Quote from: DougSpindler on February 20, 2022, 04:25:10 amYou keep jumping to the "conclusion" you came up with but dont provide any of the working (figures) to get there. $XX,000 system is meaningless without the generation/nameplate capacity. You are now dragging this out for some perverse reason.Its very very simple, for a given system:price of install / ((energy generation estimate per year) * electricity selling rate)then you have an estimate of the payback period, the above calulcators will do the hard work for you. But you won't show us how you somehow fail to do such a simple calculation. Jumping to average rates as your "defence" is stupid when we keep showing you it doesn't stack up even on worst case rates and average cost (as bolded in the original but your comprehension doesn't event pick such an obvious point up). Everything I am suggesting is worst case 10c/kWh as the selling rate, even then solar is still a profit. Unlike your endless loud claims to the opposite. Real world will be better than that through self-consumption etc.$20,794 install for 10kWh / (16,613kWh annual production * $0.1 feed in) = 12.5 yearsSo unless you are a complete moron and pay over the going rate for the system and simultaneously some how receive less than the 10c feed in tariff, that was a 12.5 year payback.Quote from: DougSpindler on February 20, 2022, 04:25:10 amand you move the goalposts once again with some bizarre claim that you won't get paid for feed in under some non-specicific and unsubstantiated circumstances. Thats called your imagination until we can see something to explain it.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 06:30:21 am
content: Quote from: nctnico on February 19, 2022, 08:07:24 pmHey, this is engineering forum and we are discussing about the future. We are discussing hydrogen for energy storage, we are discussing building lithium ion grid-tied storage systems, we are discussing about nuclear-****ing-fusion.Some of these are more difficult to engineer, some are easier.I presented the one that is simplest and lowest cost. If even that is too much for you to handle, then I guess we are doomed as a mankind. I only see continued hedonism.Or maybe you got me wrong, and I got you wrong. I'm not seeing home made Raspberry Pi DIY contraptions as a viable large scale solution; they are proof of concepts, not actual products. But you might have misunderstood the "I'm working on it" part. I'm a professional design engineer and I'm working on this for a company to come up with a professional solution which is properly documented and can be installed by any normal electrician and plumber. Just like those solar inverters, and motorized mixing valve controllers are installed every day. And by saying "I can't be the only one", I expect to see competition, which is only good.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 07:13:52 am
content: Quote from: Someone on February 19, 2022, 11:02:26 pmOhmpilot actually does quite well (according to specs, at least, I have not seen one in action), but as you say, you can get almost the same by much simpler, cheaper means. If you don't even have the GPIO out of inverter (I don't, for example), go for a simple timer: heat during the hours when PV production normally happens. It's already a huge improvement over the default of running the heatpump controlled by its outside temperature feedforward curve, making it mostly run at night time with guaranteed zero PV production and inferior COP. This is the setup I used last fall: heatpump controlled by its own internal timer feature (simply programmed from the touchscreen), and distribution circulation pump turned off with a plug-in timer during some evening hours to stop distributing that stored heat too early. Nowthisis trivial!The problem is, Ohmpilot still isn't a full optimizer. I have seen systems grow to box-after-box-after-box, and a lot of interfacing work between these boxes. Every box is sold for maybe $500, for a partial solution. It never makes financial sense.In my thinking, there should be either 0 or 1 "control brain" boxes. If the problem is trivial enough to solve without any, then by all means do that. If one is needed, it should be solving the whole problem, in this case, energy optimization.Relevant parameters are* Energy spot price* Weather forecast* Local PV production* Forecast of local PV production* Local heatpumping capability and COP estimation* Local thermal energy storage capability, and it's effect on heatpump COP (storing too much energy compromises efficiency)* Inherent energy storage capability of the building itself* Building thermal modeling in general* Possible local battery storage* Other local energy sources: fossil boilers etc.* User's patterns and preferences (when they are home, which rooms are used); it seems this pointaloneis basis of many optimization boxes* EV charging needsI know of many products that use 1-2 of the listed parameters to solve a partial problem, but do not offer significant savings compared to simpler systems, like simple timers, because they miss the obvious synergies.So yeah, when I say "simple box", I mean an electrically simple box which is cheap to manufacture. The software work that goes into it isn't completely trivial, and it needs stringent mindset to make it failsafe. And in the end it requires enough customers to make the unit price affordable. Classic chicken-egg.But this is what happened with solar inverters!They were completely infeasible first, too expensive. Now they are not, and are sold in high numbers. A lot of complex engineering goes into such product.So if we can't engineer the box I describe, we definitely can't engineer nuclear fusion or hydrogen anything.In the meantime, simple bodges work good enough, and we should just stop the destruction of existing thermal storage systems which cause no harm even if they can't be utilized to their fullest potential. And we should be also installing thermal storage to newly built hydronic installations, because at that point, the storage itself is a very small investment. The already existing demand control tools built in to modern heat pumps and PV inverters already allow simple utilization of those storage tanks. So this is not some far-fetched UFO technology, it's all existing technology which can be used right away.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 08:31:09 am
content: Perhaps the two notorious renewable energy haters with no proof in their figures would like to get out of the discussion. What applies to one little postage stamp in the world is so irrelevant to the rest of us.Ultimately things are changing. I am already selling at wholesale rates that outstrip the government scheme. My energy supplier is already working on products to help people shift their demand. When you do both of those you are onto a winner.If you are going to make outstanding claims then have some evidence or get out! This is an engineering forum not a practice session for the politics students.

author: Someone
author_rank: Super Contributor
timestamp: February 20, 2022, 09:38:18 am
content: Quote from: Siwastaja on February 20, 2022, 07:13:52 amI know of several works in that direction but they are coming from the supplier/grid/wholesale side of things, rather than giving control to end users. Hopefully some interoperability standard can be established so that we don't need brute force control methods with extra series switching (most of the appliances/loads already have enough embedded intelligence to handle being a slave to an external serial bus) and at that point it becomes clever software which can take into account all the regional/supplier/site specific oddities.... anyway its what we were promised with the introduction of smart meters in Australia, yet once they were installed the utilities (having got their no-cost meter reads and remote disconnect) mysteriously went silent.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 10:43:28 am
content: Quote from: Someone on February 20, 2022, 09:38:18 amI think that large scale / grid level efforts and distributed (households and commercial properties) efforts are pretty much orthogonal, they have different opportunities, work is needed on both levels. We concentrate too much on the large scale things only in the hope we can continue our hedonistic lifestyles without any investments, risk taking, etc. But it doesn't play out. Energy prices are increasing, the households are paying the bill anyway. So we should be doing what's mostoptimalin terms of engineering.For example, short-term thermal storage is best distributed (locally), where the use of thermal energy exists, because it's expensive and lossy to transfer heat for long distances.Seasonalthermal storage needs to be centralized, because large systems benefit from the volume/surface area ratio.On the other hand, battery storage makes more sense in large scale / grid level, because the larger installation divides down the unit cost, and it really doesn't matter where in the grid the storage is. (I'm not saying distributed battery storage is totally infeasible, though. Just the optimum bias is in larger installations.)PV is a mix of the two; centralized sites are very good (and again, electricity can be transferred hundreds to maybe just thousand kilometers), but if you have to waste good farming land to do that, it's not a good idea. Whereas distributed installations can utilize those small "wasted" areas such as rooftops which have no other use. For PV, unit cost has been already driven quite low by engineering and competition.And wind, again, is solely for large installations because of the physics; wind is available up high, or on coasts (even there, you need to build high). Unit cost is high, so each unit must be large.--Interoperability of devices is the key. This is also why "number of control boxes" must be 1, at maximum, so thatcontrollersdo not need to interoperate. We already struggle just with interoperation between the single box and solar inverter.This problem won't be ever solved by PV inverter manufacturers, or heat pump manufacturers. They have all the reasons to make the systems only operate with their own inverters. What we need is a design which comes withdriversfor most commonly available devices, and this is best done by 3rd party. The ideal is that a solar inverter can be replaced with another brand in plug&play fashion. With SunSpec compliant devices, I have this part already working; others need custom drivers which is more work.Same can be said about heatpumps. Look athttps://ctc-heating.com/products/indoor-modules/ctc-ecozenith-i555-profor example. This product is a relatively tiny 600-liter buffer tank (cost of such tank normally: 500-1000EUR) with resistive backup heaters, communication with CTC's heat pumps, and some trivial "smart" control logic and a touch screen. I have actually seen a quote for one. Guess what the price is? 4462.50EUR (+ tax). The "smart" control literally costs 3000EUR! And what can it do besides control one single brand of heat pump? It has a relay output so it can turn a gas burner etc. on.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 20, 2022, 12:57:17 pm
content: Quote from: Siwastaja on February 20, 2022, 10:43:28 amCustomers would be a lot more likely to pay for energy storage if it comes in the form of a box that's installed on their site. At least for residential, the concept of a "cloud battery" is not likely to sell well.

author: nctnico
author_rank: Super Contributor
timestamp: February 20, 2022, 01:02:32 pm
content: Quote from: Siwastaja on February 20, 2022, 06:30:21 amWith that explaination it makes a lot more sense to propose your thermal storage solution as something a large number of people can actually buy & use. So far it looked like a one-off DIY project to me. BTW: I specifically didn't go into the economics because that is very location / country dependant.A side note: did you look into preventing algea/bacteria (legionella) growth by keeping the water at over 60 degrees? I've seen you mentioning water temperatures around 30 degrees but don't know whether this is your actual operating temperature or it is just an example.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 01:47:09 pm
content: The problem we have is a lack of standardization. This is what governments are for. In the UK they botched the first roll out of smart meters, second generation meters such as mine can be transferred between suppliers with no hassle unlike the first generation ones. Government now needs to set up some sort of body to oversee the smart grid standardization. I tried telling my energy supplier to just do something that works on the zigbee network, it's already here and many of our devices are ziggbee, replace just the hub and setup your house to respond to energy prices using your existing smart home gear. They have other plans but are already working on things.The prablem is that we have 2 or 3 ways of doing this:1) A large commercial entity does it and gains immediate widespread adoption thus becoming the standard by default - but they now control the market.2) The government sets up a body that involves all manufacturers and a common standard is agreed. So no one commercial interest gets to take over but we get a decent system hopefully without scrapping what we have already.3) We leave the various commercial entities to battle it out amongst themselves and over a long time some sort of standardization and/or cross compatibility solutions will emerge - painful, slow, expensive as we constantly scrap and rebuy hardware for the sake of software features and the consumer may get left out of having a say.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 01:58:00 pm
content: Quote from: nctnico on February 20, 2022, 01:02:32 pmHeating systems are closed circuits. They do not suffer from microbiological problems, also not corrosion because the oxygen is quickly consumed, which is also why they are traditionally built with very low cost and durable iron parts. (Even if there were some bacteria in the system, nobody is exposed to it.)Domestic hot water (the one which you get out of taps and showers) needs high enough temperature to prevent microbiological problems, this would be always, constantly over 50degC, or if unsure of that, periodically higher.When heatpumps are used not only to provide heating, but domestic hot water as well, there are basically two ways to do it:* just use the heatpump up to the final temperature. The heatpump needs to alternatively switch between two storage tanks with different temperatures; one for house heating purposes, one for domestic hot water heating purposes; requiring motorized diverting valve. Basically all air-to-water heatpumps support this functionality.* use heatpump to provide just one water temperature, in a single large storage tank; that needed by the house heating circuits. In my case that varies between 30-45 degC.Preheatdomestic water with heat exchanger (copper coils inside the storage tank) to this temperature; this part happens at the full COP of the heat pump. Then, finalize the heating by a smaller resistive heater, hydraulically in series with the preheat. Legionella really isn't a thing in copper pipe coil heat exchangers thanks to water flowing without leaving dead spots, but even if there is some, it is killed in the resistive post-heating step.If significant part of year requires heating, the efficiency of the two solutions is practically same. The first strategy is superior in warmer climates where domestic hot water is a large part of total energy cost, or even cooling is needed.I use this second strategy as retrofitting it with existing energy storage units is simpler and cheaper: very small and low-power resistive boilers can be used because they are supplied with pre-heated water so hot water does not easily run out. In my case, this is 3kW and 60 liters, the white box top left in my picture.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 02:31:00 pm
content: I think legionella is not an issue in water mains systems where the water is treated. It could be further treated with UV and copper kills it also. UK pipework is copper but some is now plastic, I'm not sure what rules there are on material use.I worked on a project for hand wash units to be used in trains. We had a lot of problems there as the water stored in the carriages overhead tanks was deemed to not be sanitary and basically we had to deal with that. We had to on the one hand heat the water to 70C but on the other hand supply it at 40C and mixing with the cold contaminated water was not allowed.I think the train companies wanted to have their cake and eat it and in all likelihood the winning competitor could not do it either but just lied.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 20, 2022, 02:32:15 pm
content: Quote from: Siwastaja on February 20, 2022, 01:58:00 pmIn the US, city water has chlorine added to prevent that exact problem. Thus bacteria is more of a concern with well water.QuoteMore common is to use a "desuperheater" heat exchanger. It uses the hot refrigerant gas coming off the compressor, which is often a few tens of degrees hotter than the condensing temperature.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 02:40:50 pm
content: And remember that with legionella it's about storage, so if it's heated on demand not a problem. I have my boiler set to 40-43C so that I can shower with it directly as I do not have a mixing tap. I just open the hot water and shower.

author: Marco
author_rank: Super Contributor
timestamp: February 20, 2022, 03:58:24 pm
content: I'm surprised there are no heat exchangers for showers yet using warm water from heat pumps. Heat pumps prefer having warm water in their loop and all showers need is warm water, not hot water. As you said, legionella is only relevant for storage.Shower drain heat recovery devices are already common, add a second heat exchanger to heat up incoming water with water from the heatpump loop, finish it off with electrical heating if necessary.Some people will want hot water taps throughout a big house, but for me a small close in boiler for hot water in the kitchen is enough. All I need in the bathrooms is warm water.

author: TimFox
author_rank: Super Contributor
timestamp: February 20, 2022, 04:29:41 pm
content: Quote from: Simon on February 20, 2022, 02:40:50 pmThe legionella outbreaks I remember involved water storage and re-circulation, such as cooling towers or hotel-lobby fountains.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 04:39:23 pm
content: Quote from: Marco on February 20, 2022, 03:58:24 pmHow do you think on demand combi boilers work? The water that is heated in a combi boiler is the central heating water, this is passed around the system to the radiators , or, through a heat exchanger to heat the domestic hot water on demand.A heat pump "boiler" will work in the same way. What really annoys me is that when heat pumps are installed they take the gas boiler out. Put the heat pump in front of the gas boiler so that the gas boiler will top off the heating as required. Better to heat with gas at 95% than electric that was made from gas with 50% or less efficiency.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 05:01:23 pm
content: Quote from: Marco on February 20, 2022, 03:58:24 pmOne guy at a Finnish heat pump discussion forum haswiredpiped(?) his shower circuit from the lukewarm preheated water directly, for better COP. He actually uses it nearly everywhere except kitchen tap. As a result, he gets constant flaming to the point of bullying over his results, people claiming his setup is illegal and whatnot. Indeed legionella risk is very small as the water just goes through the copper pipe coil heat exchanger, but that doesn't prevent people panicking about it.One must be way more careful when elderly and people with immunological diseases are involved.Legionella for a normal healthy adult is a mild flu.Thismightbe an understatement. It's best to take legionella seriously, just in case, even in just small household installations.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 05:15:43 pm
content: Quote from: Siwastaja on February 20, 2022, 05:01:23 pmThey don't know what they are talking about, he is doing the same as a combi boiler. It's all about holding water at a temperature between 25 and 60C for something like 2 days. then you need it hot and it has to stay hot for a certain time to kill it. The danger is that the bacteria will multiply at these temperatures so it's as much about storage time as temperature.

author: gildasd
author_rank: Frequent Contributor
timestamp: February 20, 2022, 05:27:58 pm
content: Legionella in water is a loop hot/cold tap/shower water Issue.This a problem on ships that have such loops.It is combated by UV filtering, adding small amounts of chlorine and regular testing.I am very surprised that some household systems are made like this, makes no sense.Do you have any links so that I can avoid them like, erm, legionella in the new system I am planning.

author: nctnico
author_rank: Super Contributor
timestamp: February 20, 2022, 05:30:43 pm
content: Quote from: Siwastaja on February 20, 2022, 05:01:23 pmBuilding regulations in the NL stipulate that water must be heated to above 55 deg Celsius in devices that supply warm/hot water. If you set the temperature lower, you need to take disinfecting measures but AFAIK that hasn't been included into th building regulators yet. Over here Legionalla is taken pretty serious as there are incidents that get healthy people killed every once in a while.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 05:37:37 pm
content: Quote from: gildasd on February 20, 2022, 05:27:58 pm... and you forgot the most obvious, high enough temperature. (55degC as nctnico said as an example.)QuoteWait, what systems? Made like what? The only thing not making sense here is your comment, IMHO.QuoteLinks to what, to avoid what?

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 05:50:51 pm
content: The idea of storing excess electricity generated from solar is a very good one which is why we are already doing it.... It's called pumped storage. Works nicely and provide reactional areas. Here in California we also do it naturally, it's called rain and we use dams.As for that excess solar electricity we have in California on hot summer days many of you are saying we should use to heat-up a liquid and store it in tanks? Instead of a liquid, what if we were to use air? People in California could install a resistive element heater to maximize efficiency outside and heat the air with all of that excess electricity. No need for liquid storage tanks, fluids where bacteria can grow.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 06:03:22 pm
content: Quote from: DougSpindler on February 20, 2022, 05:50:51 pmWhat ?

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 06:08:31 pm
content: Quote from: Simon on February 20, 2022, 06:03:22 pmHe has been repeatedly told that during hot season, the thermal storage is obviouslycooled down, and used for cooling; for example, overnight. So he is just trolling, the strategy in this case is to ignore all corrective comments and repeatedly put completely stupid ideas in other's mouths to make others appear stupid. Of course, it does not work here. It's beyond me why and how such a person has found this forum.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 06:12:47 pm
content: Well some people think that hanging out with clever people makes you clever......

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 06:26:12 pm
content: The really smart people here in this post have said on hot days California's should store heat energy in a liquid and have told me to use my swimming pool. Then on cold days where temperatures are below freezing, freeze the water making ice.But what they don't tell me is how that electrical energy which is now stored as thermal can be converted back to electrical energy. Sees like a very stupid idea to me. But they are the "engineers".So I'm thinking why use water, and why not use air to store the heat energy. And instead of a tank, use the atmosphere. Thus install a heater outside the house and heat heat the air on really hot days to store all of that excess solar electricity. As I stated in a previous post makes as much sense to me as a shovel with a rope handle.Then some of the expert engineers here fail to understand how electrical energy from solar can be sold to the power company for $0.56 kWhr and purchased later in the day for $0.10 kWhr resulting in a $0.46 credit. They don't seem to grasp that with say a 4 kWhr system I can sell enough excess solar electricity to buy back 12 kWhrs. They might be good engineers, but they sure suck when it comes to finances.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 06:29:15 pm
content: You see? It repeats ad infinitum, no matter how many times it's corrected. It's nearly unbelievable people behave like this. This is also seriously detrimental to the quality of discussion.

author: DougSpindler
author_rank: Super Contributor
timestamp: February 20, 2022, 06:30:07 pm
content: Quote from: Siwastaja on February 20, 2022, 06:08:31 pmYou continue to fail to listen.... Dude, it's California, we don't need any cooling at night, we have something called the Pacific Ocean and fog which naturally provides cooling at night.

author: Marco
author_rank: Super Contributor
timestamp: February 20, 2022, 06:30:14 pm
content: Quote from: nctnico on February 20, 2022, 05:30:43 pmThe water in my shower hose never gets to 55 degrees though. The rules are really too strict, with a close in heat exchanger designed to cool down or empty the piping after the heat exchanger quickly after showering, there would be no additional risk.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 06:31:36 pm
content: Right, that will get us some respite.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 06:34:43 pm
content: Quote from: Marco on February 20, 2022, 06:30:14 pmIt should be about stored water temperature. The bacteria does not magically multiply in 5s, I think the time I had to account for was 48 hours. As we had no control over the train being out of service for periods I think we were considering just pumping for an amount of time at startup to force any old water out.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2022, 06:36:04 pm
content: Quote from: Marco on February 20, 2022, 06:30:14 pmThe idea is that all the water in your shower hose has once been at >55 degC, or continuously below about <20degC. It's mixed from cold enough and hot enough water, so it should not contain much of the legionella bacteria. Even if it stays warm for some time in the hose, this small bacterial load won't grow up to significant numbers before it already cools down to room temperature, slowing the growth down again.Now if you have storage tanks at say 35degC, or complex pipeworks with "dead legs", fed from a water source which never goes >55degC, and you feedthatwater to your shower head, the risk starts to get very real.

author: Marco
author_rank: Super Contributor
timestamp: February 20, 2022, 06:49:51 pm
content: Quote from: Siwastaja on February 20, 2022, 06:36:04 pmJust to point out the obvious, the water in my shower hose is such a dead leg, it just cools down fast and is small in volume.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 06:55:09 pm
content: Quote from: Marco on February 20, 2022, 06:49:51 pmYes but the point is that it does not sit in the shower hose at over 35C for 48 hours and then you shower with it.

author: nctnico
author_rank: Super Contributor
timestamp: February 20, 2022, 07:50:45 pm
content: Quote from: Simon on February 20, 2022, 06:31:36 pmOfftopic: Still, simply not engaging is more effective.

author: Simon
author_rank: Unknown
timestamp: February 20, 2022, 08:17:18 pm
content: Quote from: nctnico on February 20, 2022, 07:50:45 pmI tried to explain that when I was first dragged into this topic by a report but he obviously did not get the message.

author: gildasd
author_rank: Frequent Contributor
timestamp: February 21, 2022, 09:16:46 pm
content: Quote from: Siwastaja on February 20, 2022, 05:37:37 pmYes, above a certain temp on the hot loop and below another on the cold loop (tested at the furthest point, the galley and a random cabin), I also forgot testing of the feed tank and after the remineralisation filter if we want to get pedantic.On a ship, each loop goes to every subsection, then goes back to the pump. It then gets UV treated and sent back into the loop. As water is used, another pump adds more water to the loop (via a constant pressure hydrophore for the pedants).A each passage via the pump and UV, the hot loop gets heated, the cold loop cooled.Unoccupied cabins, dog legs, get a 15min drain of their showers and taps once a week.This makes sure that every user, even 100m away from the pump gets near instant cold or hot water - but makes it uniquely susceptible to Legionela.Single home systems normally do not have a hot and cold loop (except the heating, if you wash in or drink heating water, you are erm, special). Main lines go to manifolds that feed each user (bath, sink, kitchen etc). The lines thusly get drained at each use and the water cannot go over the same piece of biofilm multiple times.If a manufacturer uses a loop of sanitary water (instead of heat exchangers) that after a while gets fed into the domestic system, I would rather avoid them.Edit:They do not, I misread Siwastaja earlier post, sorry, upwards and onwards.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 26, 2022, 04:38:09 pm
content: Quote from: NiHaoMike on February 20, 2022, 12:57:17 pmOf course not but that isn't the point. The point is that utilities will install batteries when it allows they to buy cheap power and sell it later for more money.Look, i'm a big fan of rooftop solar and onsite storage. I think it makes sense in a lot of situations but not all. But when we are taking about the future of energy production we are talking about grid scale installations run by electric utilities. Claiming (as certain individials have) that nuclear power is the only answer because in some regulatory environments rooftop solar is not profitable is bananas. Nobody insists that we need basement nuclear after all.

author: nctnico
author_rank: Super Contributor
timestamp: February 26, 2022, 05:47:48 pm
content: Quote from: ejeffrey on February 26, 2022, 04:38:09 pmIt is not like that. First of all solar and wind need more surface area than is available in some areas (mostly the west part of Europe). There are no regulatory issues; in the end space is finite. Secondly switching to solar, wind and storage takes time and investments to re-organise power grids, implement storage and energy transport. And Siwastaja is making a good point: a large scale shared resource is cheaper in the end. A storage system serving a single home needs to be relatively larger compared to a storage system that serves an entire block because the load is spread more evenly. Also cabling, mounting, installation, etc costs are shared. It is the exact same reason why there is a power grid instead of everyone having a generator at home.Meanwhile, Nuclear is a good step in between by using existing technology in order to get rid of fossil fuels for electricity generation sooner rather than later. You may not agree on a personal level, but there are lots of countries planning & building new nuclear power plants in order to make the CO2 reduction deadlines that have been set. It is not like countries are going to wait until solar & wind and storage are 'ready' to supply all energy. Nobody really knows when that is going to happen. So a two pronged approach in order to make sure that CO2 reduction is achieved as quickly as possible is a better strategy (also for reducing pollution from burning fossil fuels in power plants).

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 26, 2022, 08:27:16 pm
content: Quote from: ejeffrey on February 26, 2022, 04:38:09 pmThermal storage for HVAC makes sense anywhere there's significant need for HVAC. Thermal storage for hot water is already very common. What's missing is sufficient incentives to move energy demand to off peak.

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 06:19:15 am
content: Thermal storage for HVAC requires a massively larger amount of water than that used for domestic hot water. I'm actually considering replacing my hot water tank with a gas fired tankless water heater in order to eliminate the large tank consuming valuable space in my garage.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 04:39:03 pm
content: Quote from: james_s on March 28, 2022, 06:19:15 amTankless has it's disadvantages. Tankless systems need to be flushed once a year. They require AC to work, no hot water when there's a power outage. If you live in earthquake country and there's a earthquake and water lines are broken you have several days or water in the tank.

author: Marco
author_rank: Super Contributor
timestamp: March 28, 2022, 05:07:41 pm
content: The disadvantage of tank solutions is that rainwater showers go through water in a big hurry, so with a family you end up with huge boilers. I've never seen the attraction myself, but it's a highly desirable luxury for a lot of people.Given the current situation here in Europe, I wonder if it isn't time to stop letting the market try to solve things and do megascale projects with a little gentle force.Deliver 45 degree water from ground source heat on residential scale, with storage where economic. Create cheap ready made solutions to convert most existing radiators to forced air radiators. Create close in heat exchangers to heat shower water next to the shower (basic install visible inside the shower room for free, anything more advanced for the cost of the home owner) with small electric boilers for other hot water needs.I don't think without treating this as a war and getting the margins down by central planning and large scale projects, the deadlines the EU is setting itself can be met.

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 05:18:15 pm
content: Quote from: DougSpindler on March 28, 2022, 04:39:03 pmYes I'm aware of this, there is no perfect solution, everything comes with advantages and disadvantages. I have a generator so the need for electricity is not a big problem. The earthquake issue is something to consider although I can store potable water elsewhere and hope for the best. I think if a quake is so bad that it breaks the water lines there's a good chance my house (and the water tank) will be a pile of rubble anyway.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: March 28, 2022, 06:03:33 pm
content: Quote from: james_s on March 28, 2022, 05:18:15 pmAgree that there are tradeoffs. But your need for water may be greater than you think. Damage to any part of a water system often causes a shutdown because of fear of contamination. Your house and your plumbing (and the plumbing on your street) can be fine, but still no water.I decided to skip tankless because of the high initial cost. Would take forever to recover in energy savings. Well that and the difficulty of getting the high capacity electrical circuit to the area where it would be installed. Other houses might be much easier.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 06:10:54 pm
content: One other HUGE disadvantage of tankless is depending on the input water temperature you might only be able to get 90-100F temp out. If I recall correctly if you would like 130 water out, you'll need to start with 55F water. OR you'll have to install two tankless heaters in series.

author: Marco
author_rank: Super Contributor
timestamp: March 28, 2022, 06:23:59 pm
content: He was talking about a natural gas solution though, not electrical.In my opinion the right way to do it electrically would be by heating water with a heatpump to ~45C and then using that to take cold water to shower temperature with a heat exchanger next to the shower.As I said before, the shower hose always has some standing warm water. It's about volume and speed of cooldown, not regular flushing with scalding water of all parts, that's not what happens now. With a heat exchanger near the shower the same level of safety could be reached without ever taking water above ~45C. These systems don't currently exist, but they should.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 06:33:29 pm
content: Quote from: Marco on March 28, 2022, 06:23:59 pmIn the US they are trying to get us to buy heatpump tank/water heaters. They are more than twice the cost of a tank water heater and have a motor when running some people say it can vibrate their house. What about geothermal?

author: Kleinstein
author_rank: Super Contributor
timestamp: March 28, 2022, 06:48:42 pm
content: Small scale geothermal is essentially only a "heat" source for a heat pump, that can be better than abient air in colder climate.Really hot Geothermal is viable in some places as a large installation for thousands of users, but usually not small scale. It very much depends on the location. In some locations it can be great (e.g. where you have volcanic activity and hot springs, like on island) and in other areas it just does not work.Modern heat pumps can run with low vibrations - just like modern air conditioning.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 06:54:30 pm
content: Quote from: Kleinstein on March 28, 2022, 06:48:42 pmMaybe the "Made in Germany" ones don't vibrate as much, but the ones in the US have been known to.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 06:55:08 pm
content: Quote from: Kleinstein on March 28, 2022, 06:48:42 pmI've heard of enthusiasts setting up personal geothermal heating, but it puzzles me how they keep effective control of the flow of heat in a small installation.Quote from: Kleinstein on March 28, 2022, 06:48:42 pmThere isn't really a meaningful difference between the two.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 06:57:46 pm
content: Quote from: DougSpindler on March 28, 2022, 06:54:30 pmWhoever makes the case, the guts of almost every heat pump, from the smallest fridge or dehumidifier to the largest domestic HVAC system is made in East Asia. Only the really large industrial ones seem to be made in the west now, and I don't think they've put the kind of investment into improving efficiency that the best Asian makers have.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 07:08:44 pm
content: The term "geothermal" seems to have been re-defined in this millennium.Originally, I saw the term applied to what is essentially mining natural hot water from under ground, from natural hot springs, as a powersource.Now, I received a self-congratulatory message from my undergraduate college, where they have replaced their ancient steam plant with a large heat pump, heat-sunk to an underground source of water at a temperature close to the yearly mean temperature above ground. They referred to the system as "geothermal".(An engineer I knew 50 years ago, who lived roughly 1 km from Lake Michigan in Chicago, wanted to run a heat-exchange powersourcebetween the Chicago sewer system, which is a bit hotter than Lake Michigan. I'm not sure the temperature is large enough to be practicable.)

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 07:42:08 pm
content: Isn't the reason we use gas and electricity to heat water. Isn't it because it's simple, economical and reliable? Solar thermal, geothermal, heat exchangers/heat from the sewers etc.... are complicated systems and far more costly.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 07:47:20 pm
content: That depends on the price of energy used to heat the water and the price (and maintenance) of the different capital equipment for heat pump vs. combustion.Combustion to raise the temperature of water is much less efficient than a proper heat pump, and therefore uses less energy.In fact, driving the fuel pump with a good diesel burning fuel is more efficient than directly heating the water with combustion.

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 07:50:21 pm
content: Quote from: coppice on March 28, 2022, 06:57:46 pmI don't know where most of them are made, but the Copeland compressor in my heat pump was made in the USA and as far as I know they still are, Copeland has a plant in Missouri. I expect the compressors in the popular Mitsubishi heat pumps are made in Japan but I have not confirmed this.

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 07:52:14 pm
content: Quote from: CatalinaWOW on March 28, 2022, 06:03:33 pmElectric tankless heaters on a whole-house scale are pretty much a non-starter. I would only consider tankless with natural gas. Most are 150k-199k BTU/h and to get that with electricity would require more than the entire service capacity to my house.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 07:55:51 pm
content: Quote from: TimFox on March 28, 2022, 07:47:20 pmIn some parts of the US heating oil is used. But were I live it's almost all natural gas. No one has a heat pump. And the cost for a heat pump is 3 times that of a water heater. From what I understand heat pumps are very slow to heat the water so they have heating elements. So aren't they electric water heaters/air conditioners? If you take the heat out of the air to heat the water, don't you have to run the heater to heat the house?

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 07:58:04 pm
content: Quote from: DougSpindler on March 28, 2022, 07:55:51 pmYou don't put them in conditioned space, otherwise you would have to do exactly that. One of my friends has a heat pump water heater, it's installed out in his garage which is vented to the outdoors. If I were installing one of those I'd put it in a closet with a vent to the outside so it doesn't make the garage cold either.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 08:03:06 pm
content: Quote from: james_s on March 28, 2022, 07:58:04 pmThat's my point.... there's an additional cost. But when it's cold outside the efficiency of the heat pump dramatically decreases and one has to use the electric heating element. Why pay the premium price for a heat pump water heater when you can just buy an electric one for one third the price?

author: Marco
author_rank: Super Contributor
timestamp: March 28, 2022, 08:05:16 pm
content: Quote from: james_s on March 28, 2022, 07:52:14 pmOnly in their current incarnations where they would have to resistively heat a lot of the way.If apart from a tiny bit of hot tapwater, nothing has to be heated above 45 degrees Celsius then it can all be done at high COP. Showers are where the problem is, but not an insurmountable problem because you don't shower with scalding water either.The systems as they exist are a non starter, the systems as they could be made should be started. Regardless of Nuclear or renewable, if there's a future for technological civilization the future is electric.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 08:24:01 pm
content: Quote from: DougSpindler on March 28, 2022, 08:03:06 pmYes, this is a quantitative engineering question. The more expensive capital solution will have a lower fuel cost in many applications or locations. In the case of my college's huge heat pump installation, they have a large heat sink that is at 55oF, year-round. In most domestic applications, the heat sink is the (unlimited) air outside your walls, whose temperature varies by maybe 100oF around the year.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 08:31:41 pm
content: All comes down to the initial outlay of money and ease of installation..... Electric tank water heaters cost the least. Connect 1 wire and 2 pipes and you are done.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 09:03:36 pm
content: Quote from: DougSpindler on March 28, 2022, 08:31:41 pmYes: this is a normal engineering calculation. If you can reduce fuel costs by spending capital on equipment, how many years does it take to pay for the capital expenditure?

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 09:21:23 pm
content: Quote from: TimFox on March 28, 2022, 09:03:36 pmBut homeowners do not think that way. All they care about is the initial cost.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 09:23:44 pm
content: Quote from: DougSpindler on March 28, 2022, 09:21:23 pmMost younger homeowners expect to move in a few years, so long term investment in their home only makes sense if it can be retrieved in the selling price.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 09:28:03 pm
content: Quote from: coppice on March 28, 2022, 09:23:44 pmSane in the US.

author: james_s
author_rank: Super Contributor
timestamp: March 28, 2022, 09:53:31 pm
content: Quote from: DougSpindler on March 28, 2022, 08:03:06 pmBecause a straight electric heater is far more expensive to run than a heat pump. Averaged out across the whole year electric resistance heat is about 3x the consumption of a heat pump. It has to get quite cold out before a heat pump reaches parity with electric resistance, and even when it is running backup resistance heat in parallel with the heat pump it is still less energy than a standard electric water heater.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 10:05:46 pm
content: Quote from: james_s on March 28, 2022, 09:53:31 pmCompare the price and complexity of a heat pump with an electric hot water heater. The initial cost is 3 times more. Then you have all of the added complexity complexity of a motor, valves and refringent. Far more parts to fail. I'm not so sure a heat pump water heater would ever be cost effective. It would probably fail and need to be replaced before it would ever offset the energy savings.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 10:25:55 pm
content: Quote from: james_s on March 28, 2022, 09:53:31 pmInstead of resistive heating, you can use natural gas, and use only 40% of the kWh of energy that it takes to drive the resistive heater. Now you aren't consuming much more than the heat pump, and you've paid a lot in hardware costs. Heat pumps aren't much of a win unless:Your temperatures are not too low, so the COP of the heat pump is high most of the time.Your electricity is sourced from renewable resources.Most heat pumps bought today will be replaced by the time most electricity production is truly sustainable.In the UK they are making a mockery of heat pumps by trying to use them as a drop in replacement for a boiler. This means raising water to at least 60C or 70C, to feed the existing radiators in the house. That really hurts the COP. It only makes sense to create high temperatures from a heat pump for water heating, where you need something around 50C for a good shower. Heating air to the low 20s, and passing that around the house makes much more sense, but that needs a lot more changes to a typical UK house, which has no ventilation system.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 10:29:18 pm
content: At Home Depot, prices for "regular" electric hot water heaters (40 to 50 gallon, warranteed for 6 years) range from $400 to $550.High-efficiency electric hybrid (with heat pump) hot water heaters are more expensive (warranteed for 10 or 12 years), and range from $1700 to $2700.The manufacturer (Rheem) claims an annual electricity savings of $315 per year on the 50 gallon model ($1700 price).This is an example of the trade-off of initial price vs. operating expense.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 10:33:02 pm
content: Quote from: coppice on March 28, 2022, 10:25:55 pmYou are leaving out is the cost for the energy. While natural gas may only use 40% of the kWh of energy what if it costs twice as much? The energy savings will cost you more.

author: TimFox
author_rank: Super Contributor
timestamp: March 28, 2022, 10:39:26 pm
content: Again, you need to do the calculations. The relative cost of electricity and natural gas per Joule varies around the country.Here's an advertisement from the gas company in Minnesota:https://www.centerpointenergy.com/en-us/Services/Pages/natural-gas-electricity-cost-comparison.aspx?sa=mn&au=busAccording to them, the price of gas per kwh is about 2 to 3 times lower than electricity, but that will vary depending on your location. Chicago has higher electric prices and lower gas prices than the national average.Unfortunately, most articles about prices don't convert "therms" for gas to "kwh" for electricity, which is why I cited the Minnesota advertisement.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 10:40:49 pm
content: Quote from: DougSpindler on March 28, 2022, 10:33:02 pmWe pay about 4 times as much per kWh for electricity as we do for gas. I used an energy comparison, which makes the heat pump look better.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 10:45:29 pm
content: Quote from: coppice on March 28, 2022, 10:40:49 pmWhat's conversion factor you used to convert a BTU or Therm to a kWhr?

author: cdev
author_rank: Super Contributor
timestamp: March 28, 2022, 10:48:11 pm
content: I'm guardedly optimistic about fusion but I also have to say, the likelihood of hype being behind many stories like this makes me assume that most of them are..Its like Elon Musk and his hype train.. There must be some Department of Propaganda in every country that makes these stories up. They all are similar. Take some intractable problem, and solve it in a story. Add the hero worship, the Horatio Alger like elements of the story..a grain of truth, plus some eye of newt, etc..The likelihood is that someday we wiil lol "solve" these problems, but not ass rapidly as the politicians want and probably the people who figure out how to do it wont be the ones officially anointed.. so that being the case, they might even get ripped off, the insiders might steal it, or sit on it. Until the patent expires. Thats how things work now. The insiders get rich and the rest pay and pay more. profit maximization is king..Quote from: DougSpindler on December 05, 2020, 05:21:55 amI have a friend who is involved in a similar project, here in the US. I dont think they have made any huge breakthroughs.. More like incremental progress.The proof of a success would be China no longer having to buy as much energy (natural gas, oil, etc) as they could get their hands on..--------QuoteLOL..

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 10:53:19 pm
content: Quote from: DougSpindler on March 28, 2022, 10:45:29 pmGot to love Google 1 Therm = 100​,000 Btu = 29.3 kWhIf you pay 4 times as much per kWh for electricity than gas, how much are you paying per Therm or BTU for gas?

author: cdev
author_rank: Super Contributor
timestamp: March 28, 2022, 11:03:15 pm
content: That is the lingering effects of the export ban which is now over, however the facilities to do the exporting are not finished so util they are the price wont be rising to world average levels that will probably happen in a year or two. Then the subsidy ends.. meaning the price of natural gas will go up a lot. People will have to do without or move somewhere thats warmer.. or less urban.Most of the rent stabilized less energy efficient buildings in older East Coast cities will become "obsolete" and candidates for redevelopment money. They will be torn down and replaced with market rate housing.Being older they can be declared "blight" making it possible to use eminent domain to clear them of tenants. Huge real estate developers will make billions because that land is incredibly valuable. In anticipation of this big landlords have been buying up those older budilingd cheap for quite while. The way the laws are structured the "building back better" that must be done wont include below market rate housing.That term originated in Haiti. Not much housing was built for the millions displaced by the earthquake.. But huge amounts of US tax money was funneled to the well connected developers to do so.

author: Someone
author_rank: Super Contributor
timestamp: March 28, 2022, 11:04:59 pm
content: Quote from: TimFox on March 28, 2022, 10:39:26 pmOr just consider electric vs electric as you discussed above. Electric heat pump hot water systems very quickly recover their additional capital cost:https://harvesthotwater.com.au/how-much-your-hot-water-system-costs/thats 4 years to profit, unless you are considering variable off peak/solar electricity into the mix. All very specific to the location.Quote from: DougSpindler on March 28, 2022, 09:21:23 pmRemember DougSpindler is baiscally against engineering (check their post history), no idea why they bother trying to engage on an explicit engineering forum.

author: coppice
author_rank: Super Contributor
timestamp: March 28, 2022, 11:13:49 pm
content: Quote from: Someone on March 28, 2022, 11:04:59 pmSo, a heat pump beats the most expensive way to heat water. Most impressive.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 28, 2022, 11:16:34 pm
content: Quote from: coppice on March 28, 2022, 11:13:49 pmAnd costs 4 to 5 times to purchase.

author: TimFox
author_rank: Super Contributor
timestamp: March 29, 2022, 01:28:05 am
content: Quote from: DougSpindler on March 28, 2022, 11:16:34 pmAre you familiar with engineering calculations of "pay back period"?

author: Someone
author_rank: Super Contributor
timestamp: March 29, 2022, 01:30:43 am
content: Quote from: coppice on March 28, 2022, 11:13:49 pmWell it could be contrived to be more expensive than resistive heating tank storage (solar and/or heat pump water heaters are almost universally tank storage too!), but if they are using the same priced source of energy then its only people demanding abnormally large temperature differences who wouldn't be better off. The majority of people are better off with the longer term view, average property ownership 11 years:https://homes.com.au/news/length-of-home-ownership-in-australia-reaches-10-year-peak

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 29, 2022, 01:30:42 pm
content: They should require that all new resistive heated water heaters, space heaters, and clothes dryers have a peak demand reduction device. Could be as simple as a microcontroller measuring the grid frequency, no IoT needed.

author: coppice
author_rank: Super Contributor
timestamp: March 29, 2022, 03:50:44 pm
content: Quote from: NiHaoMike on March 29, 2022, 01:30:42 pmThere is a weak correlation between mains frequency and demand, and the frequency changes very little anyway. A microcontroller would need a pretty accurate clock to detect a shift. No IoT is needed, though. Ripple control has been used in many places since at least the 1930s for load shedding.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 29, 2022, 04:56:12 pm
content: Some appliances already do this and others can easily be retrofitted for $10-$20. I live in California/PG&E customer and forced onto a Time of Use plan. During peak hours I'm paying $0.58 kWhr. (I think that's the highest rate in the world.) But during off-peak I pay $0.18. I can't think of another product where the price furcates over 30% during the day. To make things worse, the rates changed up to 5 times.Depending on when I use an appliance/consume electricity I choose when to purchase the electricity with a smart appliance. Most of the appliances in my home are programed to turn off during peak hours. So instead of paying $0.58 kWhr like many of PG&Es customers I'm only paying $0.18. I've calculated my savings to be about $1,200 per year. Or about half of what I was paying.For those of you thinking of replacing your tank water heater with a tankless, you might want to think again. With Time of Use rate plan you should be thinking of thermal storage just by adding a smart outlet to your electric hot water heater. Heat the water when the rate is $0.18, and consume when it is $0.58. I retrofitted my hot tub to with an Amazon smart outlet and a contactor/relay, Took about an hour install.Most of the posts here are about elaborate systems with heat exchangers and storage tanks. Why not do the easy least expensive stuff first?

author: cdev
author_rank: Super Contributor
timestamp: March 29, 2022, 05:16:07 pm
content: They just go by hours?What if it overcast or a cool day?They would be smart to figure out some way to communicate the demand situation and incentivise people that way..I mean, this is California, the Left Coast..not some backwater in the middle of nowhere.. Don't they have any pride? This is maybe the most important issue for you engineers, One where electronics is absolutely key.We cant waste this opportunity to do this-... RIGHT!..California should create a contest to figure out the best way to do it and experiment. Show the world how to do this the absolute best way. Also make it fun.. Make it competitive.. Have a Grand Challenge like event.. with teams..Offer prizes for best solution.Quote from: coppice on March 29, 2022, 03:50:44 pmIt sounds quite simple to sense a 1% change in AC power line frequency. But it would make ac powered clocks lose or gain time, (1% or possibly even less) I would gladly give up cheap clock accuracy for power savings.. They could use mains frequency as a means of communicating the need for power limiting fairly easily. Or use RF for signalling say over the FM subcarrier frequencies.. to tell people when power demand was high and dryer, AC use should be postponed? As I understand it Raspberry Pis already have an FM receiver chip built in to them. (its on the bottom) so it might be possible to use them for this management function. Also ultra cheap RTL2832 dongles could be used. Ive bought them for as little as $6. They make excellent digital ready FM receivers.

author: coppice
author_rank: Super Contributor
timestamp: March 29, 2022, 05:55:41 pm
content: Quote from: cdev on March 29, 2022, 05:16:07 pmWhy do you want to use new and complex approaches, including ones which have proven to be lousy (FM subcarrier control has been used, but abandoned due to too many appliances in radio dead spots), when ripple control has always worked so well? You might not care if clocks don't keep time, but millions do, including the utilities. Do you know how many millions of devices expect the number of mains cycles to be spot on over a day? Do you know what a 1% shift in mains frequency, rippling over thousands of km of interconnected grid would be like for network stability? There are reasons why grid frequency is tightly controlled.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 29, 2022, 06:15:32 pm
content: Quote from: coppice on March 29, 2022, 05:55:41 pmAnd your forgot to mention it is required by law in the US.

author: Simon
author_rank: Unknown
timestamp: March 29, 2022, 06:31:37 pm
content: Quote from: DougSpindler on March 29, 2022, 04:56:12 pmJust have a look at your own suppliers wholesale prices. UK prices vary by as much. Electricity is literally supply and demand and the price changes every 1/2 hour

author: EEVblog
author_rank: Unknown
timestamp: March 29, 2022, 08:19:09 pm
content: Quote from: DougSpindler on March 29, 2022, 04:56:12 pmYou don't need a "smart" appliance. Modern appliances like washing machines and dishwashers have a simple delay timer on them, just do the math in your head.

author: james_s
author_rank: Super Contributor
timestamp: March 29, 2022, 08:41:28 pm
content: Quote from: coppice on March 29, 2022, 05:55:41 pmI certainly care. Just in my house alone I have probably a dozen clocks that rely on mains frequency for timekeeping, not to mention the timers on my washer, dryer and dishwasher. Who even knows what other systems are out there that rely on this, an accurate 60 (or 50) Hz mains frequency is something that we've been able to rely on for decades, it would be foolish to mess with it.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 29, 2022, 09:14:21 pm
content: Quote from: EEVblog on March 29, 2022, 08:19:09 pmWhat about the appliances that don't have timers. Refrigerators, heaters, hot tub, pool pump, hot water heater, etc.? Another benefit of using smartplugs is the power company through a third app can turn off the smartplugs during super-peak energy times automatically. If you do, you get paid for not using electricity during those periods.Another reason for not doing the math in your head is the power company changes the rate up to 5 times in one day. So yes you could calculate the start time to be during non-peak, but you would also need to know the run time to calculate when it would finish AND then remember which day of the week it is. The time the rate changes is deferment depending on the day in the week.

author: Someone
author_rank: Super Contributor
timestamp: March 29, 2022, 09:28:35 pm
content: Quote from: NiHaoMike on March 29, 2022, 01:30:42 pmWhy not heat pump water heaters too? They're pretty much exactly the same thing, big thermal storage tank dribbling heat into it when available/cheap.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 30, 2022, 12:32:51 am
content: Quote from: Someone on March 29, 2022, 09:28:35 pmHeat pumps don't like being cycled on and off too often. Resistive heaters are perfectly happy being switched on and off multiple times per second. Also, a (residential) heat pump for hot water only uses 500W or so.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 12:43:01 am
content: Quote from: NiHaoMike on March 30, 2022, 12:32:51 amHow do you figure 500W? Take a look at the specifications... It appears you are after by a factor of 10.https://images.thdstatic.com/catalog/pdfImages/73/73236cfd-10b6-415f-9e54-6bce99317265.pdf

author: Someone
author_rank: Super Contributor
timestamp: March 30, 2022, 12:50:21 am
content: Quote from: NiHaoMike on March 30, 2022, 12:32:51 amGrid side demand management is rarely (never?) switching at such extreme rates, even a simple deadtime would suffice as is commonly done for other motors like pumps. This has been shown to be effective for solar self-consumption which is possibly the fastest fluctuating demand management in residential installations. The conversation was dominated by off-peak/variable tariffs, either way thermal storage is able to cover daily fluctuations, and heat pumps can easily do that work (more efficiently) in place of a resistive heating method.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 30, 2022, 02:30:13 am
content: Quote from: DougSpindler on March 30, 2022, 12:43:01 amThere's also a backup resistive heater if it gets too cold for the heat pump to operate, the 37F limit is likely to prevent the possibility of it cooling down the space to the point where pipes could freeze, it's not hard at all to design a heat pump to work well below freezing.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 02:32:39 am
content: Quote from: NiHaoMike on March 30, 2022, 02:30:13 amBut can you do it for 500 watts as someone claimed?

author: EEVblog
author_rank: Unknown
timestamp: March 30, 2022, 04:16:06 am
content: Quote from: DougSpindler on March 29, 2022, 09:14:21 pmSwitch to a provider that doesn't do that?

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 05:46:32 am
content: Quote from: EEVblog on March 30, 2022, 04:16:06 amWish I could. Provider is PG&E. You know the power company that is responsible for starting those massive wildfires in California which killed, no murdered over 100 people.

author: james_s
author_rank: Super Contributor
timestamp: March 30, 2022, 06:11:42 am
content: Quote from: DougSpindler on March 30, 2022, 12:43:01 amThat's the auxiliary resistance element that's rated 4500W, about the same as a standard water heater.The compressor is 4200 BTU/h so about 1/3 Ton, which is about 1/3 HP so about 300-350W. How often the electric element runs I don't know. I do know the heat pump water heaters do work, and they are considerably cheaper to run than a conventional electric water heater. Whether it makes economic sense depends on how much you pay for electricity and how long you intend to live there.

author: Simon
author_rank: Unknown
timestamp: March 30, 2022, 06:56:10 am
content: Quote from: EEVblog on March 30, 2022, 04:16:06 amYou are either in the deal or not. Grid prices change all the time, 48 times a day in the UK although the step change is not big that often, so if you want to save you have to follow the money, the money follows supply and demand.

author: james_s
author_rank: Super Contributor
timestamp: March 30, 2022, 05:12:41 pm
content: Quote from: Simon on March 30, 2022, 06:56:10 amThat's something I'm glad I don't have to deal with here. My electricity price has changed once in recent memory, it used to be around 8.2c/kWh and now it's 10.1c/kWh. There is only one provider so there is none of this nonsense of having all these different companies to sell me the same stuff from the same place delivered over the same wires.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 05:47:24 pm
content: Quote from: Simon on March 30, 2022, 06:56:10 amI find what you are saying hard to believe, so maybe I'm not understand you. Are you saying in the UK the cost you pay for electricity changes every 30 minutes? So in one half hour period you might be paying say 15p and 30 minutes later 45p? That's ridiculous.

author: Simon
author_rank: Unknown
timestamp: March 30, 2022, 06:03:08 pm
content: Quote from: james_s on March 30, 2022, 05:12:41 pmi am refering to the wholesale price. as a customer you never see this unless you sign up to a tariff that specifically tracks wholesale rate. No matter your locality there will be a supply/demand auction going on to get power from different suppliers, you simply pay the averaged retail price to bean counters who may not even be generators themselves.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 06:09:27 pm
content: Quote from: Simon on March 30, 2022, 06:03:08 pmI thought we were talking about residential. In the US, for PG&E customers our rate can change 5 times in one day. One hour we can be paying $0.17 kWhr and the next $0.58.In the US wholesale rate are billed per minute.

author: james_s
author_rank: Super Contributor
timestamp: March 30, 2022, 06:26:08 pm
content: Quote from: DougSpindler on March 30, 2022, 06:09:27 pmThat's really bizarre. PSE rates are printed right on the bill, there's a base rate and then over a certain kWh threshold you pay a bit more per kWh but it never just changes between billing cycles.

author: Someone
author_rank: Super Contributor
timestamp: March 30, 2022, 10:12:22 pm
content: Quote from: james_s on March 30, 2022, 06:26:08 pmNote the toll like behaviour, never mentioning the specific tariff/contract (or that alternatives are available) just repeating the same misleading point over and over. Changes 5 times per day could be from an:off peak - shoulder - off peak - peak - shoulder - off peakdaily pattern (or various similar ones), 5 changes but only 3 different rates. PG&E offer as their simplest plan a 2 rate tariff covering evening peak, and all other use. So they dont have a fixed rate tariff available, but its not like they are forcing people into complex and variable pricing.Quote from: Simon on March 30, 2022, 06:03:08 pmExactly this, people arent forced onto complex or variable tariffs, but in many places they can choose to. How many more pages do we need of this nonsense?I would like a wholesale tracking plan, Australia does 5 min wholesale pricing and 15 minute residential billing, but wholesale priced plans are not available here for residential customers.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 30, 2022, 11:52:18 pm
content: Quote from: Someone on March 30, 2022, 10:12:22 pmYou should take a look at PG&E's residential rate plans, they have 13 of them. And just to be clear PG&E has NO shoulder pricing. Feel free to read the details of each of the rate plans on PG&E's and the PUC web site. Here are the 13 rate residential rate plans one can be on. E-1, E-6, E-7, E-9A, E-9B, EV-A, EV-B, EV2-A, EV-B, ETOU-A, ETOU-B, ETOU-C and ETOU-D.Crap and since you made me look I see PG&E just raised the rates for the plan I am on. I'm not paying $0.60 for peak and crap $0.26 for off-peak. That's a $0.02 and $0.08 kWhr increase since the beginning of this month. Each rate plan is different, but we pay 6 different prices throughout the year. The 6 prices are broken down into 3 prices in the winter, and 3 for summer. But that's for the rate plan I am on. Some of the other are the same and other are different. You have to read the rate plan agreement.Got a question for you.... Is $0.60 kWhr the highest amount residential customers in the US or for that matter anywhere else in the world an electricity? What sucks is the next town over, about 5 miles from me, customers are paying $0.15 when I am paying $0.60. Would you agree PG&E is fucking with their customers and screwing them?

author: Someone
author_rank: Super Contributor
timestamp: March 31, 2022, 12:47:35 am
content: Quote from: DougSpindler on March 30, 2022, 11:52:18 pmE-6:Sure looks like it has shoulder pricing (as does EV, and EV2). Which would be:off peak -2pm- shoulder -4pm- peak -9pm- shoulder -10pm- off peakBut you still won't say which plan you are on that has 5 price changes a day and .60c/kWh at peak, toll on, tollololol on. Also half those tariffs you claim to be able to access arent publicly listed (or dont exist).

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 02:13:48 am
content: Quote from: Someone on March 31, 2022, 12:47:35 amDude can't your read? Do you see the word shoulder? I don't. As you can see PG&E has peak, partial-peak and peak, NO SHOULDER as you claim.Just received a letter in today's mail from PG&E offering us a "Lower Price" if we switch to the ETOUC rate plane.https://www.pge.com/en_US/residential/rate-plans/rate-plan-options/time-of-use-base-plan/tou-everyday.page?WT.mc_id=Vanity_toueverydayRead the fine print. This is a tiered TOU rate plan andNOTE THERE IS NO SHOULDER PRICING?https://www.pge.com/en_US/residential/rate-plans/rate-plan-options/tiered-base-plan/understanding-baseline-allowance.pageIf we were two switch to this "lower rate" plan it would cost us $750 more per year.PG&E continues to deceive and screw their customers saying the prices are lower. Why yes they are, but when you factor in TOC and tiering customers are having to pay much more. And if they installed solar panels, they are doubly screwed because PG&E doesn't do one for one exchanges on excess kWhrs. With this TOU rate plan customers will have to sell PG&E 1.5 kWhrs during the day/off-peak to get just one back during peak. Look at the rate, it's over $0.50 kWhr during the summer on the higher tier.https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_SCHEDS_E-TOU-C.pdfAs I stated earlier I am on the EV-A rate plan which is nearly identical to the EV-B rate plan. This rate plan is straight TOU, non-tiering,NO SHOULDER PRICING.Dang are customers about to get screwed.... Especially the ones who already have solar.

author: Someone
author_rank: Super Contributor
timestamp: March 31, 2022, 02:45:21 am
content: Illustrative example:Quote from: Someone on March 30, 2022, 10:12:22 pmQuote from: DougSpindler on March 30, 2022, 11:52:18 pmQuote from: DougSpindler on March 31, 2022, 02:13:48 amOh so we have to say:off peak -2pm- partial-peak -4pm- peak -9pm- partial-peak -10pm- off peakbecause that is entirely different and nothing at all the same.Now a troll and a literal pedant, or will you insist its not trolling as you want to call it being precise and disruptive? Yet you miraculously still avoid mentioning what plan you are actually on.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 02:52:23 am
content: Quote from: Someone on March 31, 2022, 02:45:21 amDude if you can read you owe me a HUGH apology or are you just trolling and stirring the shit pot. Reading the second to the last line in my last post. I keep answering your question and you call me a troll. That's not very nice.

author: Someone
author_rank: Super Contributor
timestamp: March 31, 2022, 03:57:23 am
content: Quote from: DougSpindler on March 31, 2022, 02:52:23 amQuote from: DougSpindler on March 31, 2022, 02:13:48 amPedantry, you never mentioned you were on this plan before this point. Still...Quote from: Someone on March 31, 2022, 12:47:35 amPG&E does not list EV-A or EV-B:https://www.pge.com/tariffs/index.pageThose are rates of larger plans/contracts.EV rate A has peak consumption at 60.355c/kWh, but only 3 daily tariffs of 4 daily changes:off peak 24.689c/kWh -7am- shoulder 35.944c/kWh -2pm- peak 60.355c/kWh -9pm- shoulder 35.944c/kWh -11pm- off peakQuote from: DougSpindler on March 29, 2022, 04:56:12 pmchanges 5 times? still not there yet. Again:Quote from: DougSpindler on March 30, 2022, 06:09:27 pm$0.17 to $0.58 jump in a single step, nope, no evidence of that. So you can try and find some tiny slice of truth, but most of its still unsubstantiated nonsense, about a plan you chose to use.So where is this plan that has 5 daily changes of rate? Or are you going to point to a weekday changeover between seasonal rates and include the two different off-peak tariffs, then claim "victory". 2 days (at best) at year with predictable and well known in advance pricing changes is not something to be spamming up the forum about. You chose the plan, if you dont like it there are simpler ones!Hugh apology, just for you:

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 04:17:04 am
content: Now I know you are a fucking troll. Please stop with your lies and false claims.Right from PG&E's web site.https://www.pge.com/en_US/residential/rate-plans/rate-plan-options/electric-vehicle-base-plan/electric-vehicle-base-plan.pageWhat is the EV-B rate?EV-B rate separates your vehicle’s electricity costs from those of your home. It requires the installation of a second meter. The price for charging varies based on the time of day. Your home energy use is measured separately through its own rate.The EV-B rate is best for those who want to track their EV charging separately from their home energy usage and/or are not able to shift their home electric use to off-peak hours.Remember: you can maximize your saving by reducing usage from 7 a.m. to 11 p.m. on weekdays, and 3 p.m. to 7 p.m. on weekends and holidays.Time-of-use (TOU) periods and costsThe EV-B rate is a Time of Use (TOU) rate. This means there are different prices for electricity depending on the time of day. Costs on EV-B are lowest from 11 p.m. to 7 a.m. when energy demand is lowest. This is the best time to charge your vehicle.Electricity is more expensive during peak (2 - 9 p.m.) and partial-peak (7 a.m. - 2 p.m. and 9 - 11 p.m.) periods.The cost to charge your EV during off-peak hours is the about the same as paying $1.96 per gallon. Learn more about eGallon.Opens in new Window.The EV-B rate is not eligible for the CARE and FERA monthly discounts.DOWNLOAD EV-B FULL SCHEDULE AND RATES (PDF, 430 KB)PDF. OPENS IN NEW WINDOW.Lowest costs - ideal charging times 12a.m - 3 p.m. Higher cost - avoid or limit charging: 3p.m. - 12a.m.

author: gnif
author_rank: Unknown
timestamp: March 31, 2022, 04:21:12 am
content: Settle down guys or this thread will be locked.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 04:22:56 am
content: Quote from: gnif on March 31, 2022, 04:21:12 amLock it, The guy is being a dick and a bully. I am the original poster and he has ruined it for everyone.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 31, 2022, 05:08:36 am
content: So if I understand the rates correctly, the cheapest would be to get the EV2-A plan and put your bulk of energy use in the 12AM-3PM time. Should be fairly easy to do with the help of automation, no battery storage needed. (That's assuming it's possible to get that plan without owning an EV or stationary battery system.)

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 05:30:56 am
content: Quote from: NiHaoMike on March 31, 2022, 05:08:36 amIt's almost worth it to buy an EV just to get on the plan. EV-A is closed, but EV-B is still open. EV-A has been replaced by EVA-2 which isn't as good. Ideally one would want to sell as much energy to PG&E between after 2 pm to sunset what PG&E is paying $0.60 kWhr. And then buy back as much electricity as you can from Midnight to 7AM and on weekends when the rate is $0.18. Starting on August 1st this is about to change and PG&E in their effort to lower prices is redefining off peak to be midnight to 3 or 4 pm or daylight hours. So instead of getting $0.60 kWhr customers will only get $0.15. I will now have to sell PG&E 2 or 3 kWhrs (off-peak) to buy one back during peak. People who have solar and not had to buy any kWhrs from PG&E due to 100% offset are in for a surprise. They might need to double the size of their solar system to get 100% offset once the rates and TOU times are redefined in August.

author: Simon
author_rank: Unknown
timestamp: March 31, 2022, 07:36:47 am
content: The simple fact is that electricity is going up in price. My supplier has a tariff where you buy and sell at wholesale linked prices, you sell at wholesale and buy back at 2x wholesale. This used to be good when during the day it was over 5p/kWh wholesale as that is what the government pays you through other suppliers and the price may climb to 10/12p on exceptional days or at certain times of day. You would then change you usage patterns to use power when it was at it's cheapest. This was worthwhile. But now the wholesale price has flatlined thought each day but for the 16:00-19:00 peak.Attached is the graph of today's prices, the weather is not good at the moment but we are getting quite a bit of wind and solar is not doing bad considering we have our first light dusting of snow here for the 21/22 winter. Now if you look at wholesale prices and then look at where the power is coming from:https://gridwatch.co.uk/the price makes sense, these days I look at my prices for tomorrow and guess what the weather will do based on the price.

author: f4eru
author_rank: Super Contributor
timestamp: March 31, 2022, 10:35:47 am
content: Please lock the thread.it's totally offtopic anyway.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 31, 2022, 12:34:46 pm
content: Quote from: DougSpindler on March 31, 2022, 05:30:56 amSo minimize what you use on peak and push what you can to off peak?

author: Simon
author_rank: Unknown
timestamp: March 31, 2022, 01:32:42 pm
content: Ideally if the price is so variable or the difference between what they pay compared to what they charge is large you have storage but batteries are still quite expensive for the home unless you go the DIY route and pray your home insurance does not ask why your house wend up a little bit like a lithium fire when you claim.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 31, 2022, 01:47:22 pm
content: Quote from: Simon on March 31, 2022, 01:32:42 pmIf a large amount of the peak time use is thermal, thermal storage is a lot cheaper.

author: Simon
author_rank: Unknown
timestamp: March 31, 2022, 02:33:49 pm
content: Quote from: NiHaoMike on March 31, 2022, 01:47:22 pmThat is the basis of the scam artists at myenergi, they produced a device to control power to a heater to use solar power rather than export the solar, then they claim to be "green" when doing this is far from green in fact the opposite.For as long as we use gas to make electricity it is better to heat water with gas not electric. Production of electricity with gas is sub 50% efficient, could be as low at 30-40%. But a modern gas boiler is over 90% efficient. Meanwhile exporting that solar means that less gas is used in power generation where over twice the gas is being used to make electricity that would not be needed if the baby boomers that "invested" in solar were not so greedy having already been paid up to 4 times the retail value for the electricity they generate.....The zappi charger is not much greener either as it has nothing to do with shifting consumption avoiding say that we resort to coal for brief periods.

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 06:22:33 pm
content: Quote from: NiHaoMike on March 31, 2022, 01:47:22 pmHow would one do it? What would be the cost?

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 06:30:28 pm
content: Quote from: NiHaoMike on March 31, 2022, 12:34:46 pmThat's what I've been doing with smartplugs. I've had to modify smartplugs for 220v appliances. But here's the thing. That will work great until PG&E's rate change goes into effect for customers with solar panels. I will have to sell them 2 or 3 kWhrs just to get one back during peak. I have 20 panels right now and for the past 3 years we have been over producing and having to give PG&E $1,100 of free electricity every year. With the new prices for solar I'm thinking I'm going to have to add 10 more panels just to try and come close to 100% offset. I think I will need more like 15.What PG&E is doing is just screwing everyone who has installed sola panels. And they are trying to make it worse.

author: Someone
author_rank: Super Contributor
timestamp: March 31, 2022, 10:15:04 pm
content: Quote from: Simon on March 31, 2022, 02:33:49 pmAs the OP keeps noisly bringing up, when to use solar production is mostly determined by the tariff structure (getting paid the fully loaded retail import price for exports is anomalous/unsustainable, its a huge subsidy). If you get paid a lower rate for solar export than for off peak imports, then self consumption of solar electricity generation for thermal storage in domestic hot water makes financial sense. Whether that makes sense environmentally depends on what other energy source that would offset. But if environmental cost is your primary concern, then you're back to a heat pump storing thermal energy from the lowest carbon electricity you can source. Hot water from a heat pump even when powered by electricity produced from gas, can be greener than gas directly.Quote from: Simon on March 31, 2022, 02:33:49 pmYes, with current daily load following in the UK being done with gas plants this adds up if youonlyconsider gas vs resistive hot water. Even that contrived framing doesn't apply in Australia, or other countries where solar is a larger component and gas is predominantly used for evening peaking. This will also change over time, with batteries and other storage coming online reducing the need for gas peaking.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 31, 2022, 10:32:53 pm
content: Quote from: DougSpindler on March 31, 2022, 06:22:33 pmMake hot water or ice when there's excess solar, use it for heating or cooling later. It ends up a few orders of magnitude cheaper than batteries for any substantial amount of storage.Quote from: DougSpindler on March 31, 2022, 06:30:28 pmHave you already done what you can to minimize peak time use even if it means using a lot more off peak?

author: DougSpindler
author_rank: Super Contributor
timestamp: March 31, 2022, 11:27:16 pm
content: Quote from: NiHaoMike on March 31, 2022, 10:32:53 pmI have done everything I can do to sell as much solar surplus electricity at peak rate, and consume as much as I can during off peak. I'm using smart plugs and they work perfectly. For 220v appliances I'm using contactor/relays. Working perfectly. I created smart-plug group which turns appliances off during peak and on during off-peak. But in August when PG&E drops the rate they pay for excess solar electricity everyone with solar will have to start buying electricity from PG&E at the peak rate. For me, it will be $0.60. Right now we are over producing $1,100 of electricity per year which we have to give to PG&E for free. Starting in August we will have to buy $700 worth of electricity from PG&E.

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 12:47:48 am
content: Quote from: DougSpindler on March 31, 2022, 11:27:16 pmYou're never forced to sell for 0.0c, ever. And you're not forced to buy electricity ever. So thats just more fear mongering nonsense. Point to actual plans/rates/announcement instead of your sensationalist lies.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 01, 2022, 03:51:51 am
content: Quote from: DougSpindler on March 31, 2022, 11:27:16 pmSounds like your strategy to "sell" as much as you can is wrong if you end up building up so much excess that you end up giving it away. Perhaps try using more as it's being generated and sell less?

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 05:20:51 am
content: Quote from: NiHaoMike on April 01, 2022, 03:51:51 amPutting the pieces together it seems like they are on some plan where they sell at exports at almost the full retail price of the TOU plan:Quote from: DougSpindler on February 19, 2022, 08:13:50 pmPeak, Shoulder, Off-Peak prices, differing rates in summer and winter = "6 different prices". The buy/sell margin is currently unrealistic:Quote from: DougSpindler on February 19, 2022, 08:13:50 pmThen the (proposed?) incoming changes to the plan/rates include:Changing the peak and shoulder times to match the current wholesale market (no longer coinciding with peak solar production times as they have plenty of solar production now)Changing the rate at which solar exports are paid to match the "avoided cost" of generationWhen you look at how the current billing is divided these changes make sense, there are no daily connection/supply charges and its all lumped on as a tax/tariff on kWh of use (attached below). So the prior method of calculating solar exports was crediting exporters back the operating expenses of the network, above and beyond the actual costs of generation that the solar was offsetting. Lunacy!Queue the noisy fat cats who were causing everyone elses bills to be so high making out like they are being hard done by.... we saw the same thing in Australia around franking credit refund for retirees, a bizarre negative tax (https://australiainstitute.org.au/post/cashed-up-retirees-getting-a-refund-for-tax-they-never-paid-weve-hit-peak-rort/). Same thing here, sending power to the network shouldn't result in someone being paid as a network operator, since they aren't. It was probably a convenience in accounting when the scheme was first setup, but has turned into a nasty loophole that is damaging to the market.

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 06:17:29 am
content: There's your problem!Random day (29/03/2022) of California ISO wholesale market data tells it like it is.

author: dietert1
author_rank: Super Contributor
timestamp: April 01, 2022, 10:31:41 am
content: Is this averaged over year?I think these data show a market chance for people/institutions who build storage for electrical energy, e.g. gravitational storage like i mentioned above. Total storage needed would be about 9 hours times 10 000 MW. Earnings could be about 2.4 million dollar per day (12 hours x 10000 MW x 20 $/MWh).Regards, Dieter

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 11:22:27 am
content: Quote from: dietert1 on April 01, 2022, 10:31:41 amThat was just a single recent weekday, the pricing is wild. Running gas fired base load while negative wholesale pricing? Likely some really weird long term supply contracts behind that. You can see why they want to move the peak pricing to the evening and pay very little for daytime solar production.

author: DougSpindler
author_rank: Super Contributor
timestamp: April 01, 2022, 01:44:22 pm
content: Quote from: Someone on April 01, 2022, 12:47:48 amDude I, just like every PG&E customer who has solar who wants to remain attached to the grid must enter into an Net Energy Metering agreement and select an electricity rate plan. Instead of trolling and making false claims in your posts as you have in the past, try reading the documents. You’ve been given the links.

author: Simon
author_rank: Unknown
timestamp: April 01, 2022, 05:06:24 pm
content: Quote from: Someone on March 31, 2022, 10:15:04 pmWhen you have been paid 4x the retail value (about 8 times the wholesale value) clinging onto that power is just taking the immoral piss.The myenergi product developed to heat water was well before heat pumps, yes if the home owner upgraded to heat pumps at a cost of £10'000 that would work but remember assuming the product supports a heat pump, we are talking about people that only "invest" they never gave a shit about the environment.It's not just how the power is produced at any time but as we all know the losses in power transmission are exponential, the whole advantage of micro generation is to supply power locally thus taking load of a strained infrastructure and making for more efficient transmission too. but no, you get home in the summer when the demand is peaking and you plug in your car that charges from your panels from electricity you have already been paid to generate leaving the whole infrastructure to go screw itself.

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 09:39:47 pm
content: Quote from: DougSpindler on April 01, 2022, 01:44:22 pmYes, have read the links (and more). Nowhere are people being forced to sell electricity for 0.0c (free) or forced to buy specific amounts. Thats what you claim above, in the quote you re-quoted. Its not true, you say it is, but cant point to the agreement that makes it happen. I'm not going to do an exghaustive search though the entirety of every possible contract (many of which are not publicly available) in your market. If you say there is such a horrible agreement that you are "forced" into then it should be trivial for you to show a) what that agreement is and b) why your generation and consumption make it that way.Since you think it is so obvious, why not point to this new plan which requires you to give them electricity for free?You keep picking sensationalist figures out of a larger picture, which you won't reveal. The solar feed in were only offered to people who were producing close to their overall use, so what is your balance of generation/consumption? feel free to break down that consumption into the different TOU tariffs if you like (the generation from solar can be easily estimated). Yes, you did have a "good" deal for you where solar exports were sold for very high prices. But that was so far above the actual market rate, and so many people were doing it, that the market collapsed. Now that market needs a re-adjustment, and you will be worse off. I have not even seen any mention of curtailment/blocking exports during peaks, it looks like the plan is to continue paying for exports (even during negative price/overloaded market). Getting paid less for your exports is not being paid 0.0c.But you arent forced to buy or sell electricity in any specific volumes or specific prices, that choice is yours.Even in the worst case if the export tarriff was 0.0c (or negative, either way unproven/unsubstantiated) you could self consume that energy, as people here keep saying, its your resource to do with as you please.I'm 99% sure I could re-write this to be accurate/true, going fromQuote from: DougSpindler on March 31, 2022, 11:27:16 pmto something like:Right now we are over producing electricityeach year which we will be paid $X,XXX less for by the new rates.Starting in Augustunder the new rates we will buy electricity from PG&E at higher prices, increasing our costs by $XXX.That assumes you make no changes to your behaviour, except the market is telling you that what you are currently doing isnt working, and you need to change your behaviour.

author: Someone
author_rank: Super Contributor
timestamp: April 01, 2022, 09:59:00 pm
content: Quote from: Simon on April 01, 2022, 05:06:24 pmYou're the one who reframed the argument around environmental, when the discussion was about economic (bolded). Different priorities give different plans/outcomes. Not sure how using green power is "immoral" when the economic advantage is to sell it, that opening line makes no sense.Yes, the most common/dominant UK hot water system is that byzantine combined heating system. But again, thats a choice, if the replacement costs are so high, you could equally install a separate hot water unit and "split system" heat pumps around the house (as most other countries do). Why is that not common in the UK? Because historically the differential price of electricity to off-peak electricity or gas (used for that heating) favoured the storage systems. Thats no longer the case, like the OP, you can get all grumpy but the market is changing where what used to be profitable/economic is becoming uneconomic. Or, acknowledge that the energy pricing structures of 5, 10 years ago arent coming back, and that things might have to change.P.S. even refitting a boiler direct to a heat pump is becoming profitable:https://www.dailymail.co.uk/news/article-10675685/Heat-pumps-CHEAPER-lifetime-gas-boilers.htmlDepending on who you believe, the lower maintenance and longevity of a heat pump can end up with a lower fixed cost per year (before the savings in marginal fuel costs).I'm 100% backing NiHaoMike here, if the majority of peak power (universally the short evening peak) use is from HVAC and/or hot water for a customer then thermal storage is a no brainer. Could be as simple as some insulation and pushing the house a few degrees cooler/warmer in the afternoon, then riding out the peak with the HVAC off/fan/circulate-only.

author: Simon
author_rank: Unknown
timestamp: April 02, 2022, 06:33:05 am
content: If you know all about the P&G plans you post them instead of ranting all the time.

author: DougSpindler
author_rank: Super Contributor
timestamp: April 02, 2022, 03:39:25 pm
content: Quote from: Someone on April 01, 2022, 09:39:47 pmNo you haven’t or if you have you cannot comprehend or understand what you are reading. YOu my friend are ranting about something you do not know about. Or are just a troll attempting to ruin this site for others.

author: Simon
author_rank: Unknown
timestamp: April 02, 2022, 08:16:52 pm
content: How about:1: one of you put some links in to back up your petty argument2: both get out of the thread3: do I lock it as you insist in arguing like children!!!

author: DougSpindler
author_rank: Super Contributor
timestamp: April 03, 2022, 04:28:42 pm
content: Quote from: Simon on April 02, 2022, 08:16:52 pmWe are all here to learn and share information. Why not start by apologizing for the insults you’ve posted in the past.Then re-read the information in the inks I have provided and apologize and correct the lies you previously posted. If you are kind and have something nice to say, people are much more likely to engage in a meaningful conversation with you.Instead of brining your preconceived ideas and a closed mind, try listening and reading information others are posting as you might learn something and become better educated. The world id full of dummies, just look at politicians.I have posted links in the past which you claim to have read, but your posts after you claim to have read them contradict what is in your post.Re-read the links I have posted previously and fell free to ask questions or challenge me to supply supporting evidence so you can see the source material I am quoting. Everything I have posted can be found on PG&E/s web site and The California Public Utilities Commission web site. And don’t mixup Net Energy Agreement (NEM) with customer rebate plans. I previously listed the 13 rate plans residential rate plans customers can be on. There are two NEM agreements with a third one pending. PG&E customers with solar MUST be on one customers rate plans AND agree to one of NEM agreements.As I have stated in previously, PG&E has made this very complicated with 13 different rate plans and three NEM agreements.