Wind turbines might not be that great afterall - Page 1
Forum section: electronics / general

author: DougSpindler
author_rank: Super Contributor
timestamp: October 04, 2020, 04:22:15 pm
content: Interesting discussion about the disadvantage of wind turbines other than no one want's them where they live.I question one of facts presented. The life of a wind turbine is about 20 years. Why so short? That's less than coal and nuclear power plants. I would think a wind turbine would be more on the order of 40 or 50 years. But then again we have a very large wind turbine generating facility with nearly 5,000 wind turbines. I read they decommissioned about 25% after 20 years because of bird/bat hitting the blades and costs. Turns out the older ones were too costly to maintain, the technology was too old, as was the power output was too little.If what's in the video is correct wind sure doesn't seem that great in the long run.

author: tom66
author_rank: Super Contributor
timestamp: October 04, 2020, 05:08:59 pm
content: Because so many people object to building wind turbines near them in the UK, they tend to be built offshore now. This is true for the UK but I have heard other things from the rest of Europe. No doubt that significantly increases the cost of maintenance and installation and probably also affects the lifespan of the turbine (salt spray, wind, potential ship collisions etc.)Personally I would much rather have turbines a few miles away than a coal or natural gas plant 10 miles away. I think they are quite pretty and I admire the beauty of mankind capturing energy from nature.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 04, 2020, 05:14:41 pm
content: Quote from: tom66 on October 04, 2020, 05:08:59 pmBut what about end of life? What do to do what the tons of carbon fiber and the massive cement foundation?

author: Gyro
author_rank: Super Contributor
timestamp: October 04, 2020, 05:59:46 pm
content: As I type, wind energy is generating 17% of the UK's energy needs and we go weeks [Edit: / months] on end without burning any coal.20 years is a huge timeframe in such a rapidly advancing technology, efficiency is going up all the time. Early wind turbines suffered from rapid wear of their gearboxes due to stop start operation and fretting of the gear teeth that were engaged when the rotors were stationary. The early ones are probably repairable, just not economically viable these days, when their site can be used for a more efficient one. Modern direct drive designs are far more efficient and require far less maintenance, making them very suitable for offshore wind farms.The foundations and steel towers, if constructed properly can be re-used, with just replacement of the working heads so recycling costs are minimal. Steel and copper are obviously completely recyclable, the lightweight composite blades can be used as filler material (as shown at the end of the video) - you need a supply of the raw material before you can realistically scale up the processes. Anything that reduces the digging up of virgin countryside for gravel extraction for building use has to be a good thing.Why keep digging up non peer reviewed information [Edit from] Youtube videos as source material? Do you feed it to your students too?

author: tom66
author_rank: Super Contributor
timestamp: October 04, 2020, 06:09:23 pm
content: Well, there's no perfect energy source.That video states things like, access roads and cabling need to be put in for wind. Well, the same is true for solar, coal, nuclear, etc. Possibly, wind turbines could require more cabling, due to their sparse nature, which is a possible strike against them, but then it's not as if other more centralised sources of power, like nuclear, are carbon free either.Then it states 500k birds are killed every year by wind turbines. But over 1 billion (10e9) are killed every year by the domestic cat, in the US alone ; so if we are truly concerned about bird life, shouldn't we be worrying about cats instead?The recycling aspect of wind turbine blades is going to be a headache, but I suspect at least some of it can be deferred by keeping existing turbines running for as long as possible. Old turbines are perhaps decommissioned because their power output is too low and they could be replaced with more powerful turbines. If the turbine is, say, 5MW instead of 100kW, it perhaps makes more sense to keep it running. As the author states, there's no perfect option; if you burn coal or natural gas, sure, you don't have to recycle anything, but you're using the atmosphere to recycle the waste products from the combustion, and that definitely isn't sustainable. It sounds like if a wind turbine produces, say, 24 tonnes of waste (8 tonnes/blade) at the end of its life, but it lived 35 years, then that may be an acceptable trade off, especially so if 50% or more of that waste can be recycled into something else.https://www.nature.com/articles/ncomms2380

author: themadhippy
author_rank: Super Contributor
timestamp: October 04, 2020, 06:23:59 pm
content: Only 20 years life span or half that of the original nuclear sites,however several wind farms down the line and they'll still be decommissioning the nuclear site and giving future generations a big pile of radioactive crap to play with.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 04, 2020, 06:52:07 pm
content: Quote from: tom66 on October 04, 2020, 06:09:23 pmI've heard this argument before as if there is only one species of bird. Can we look at the facts? The birds domestic cats go after are small, abundant, and not endangered. These are not the bird being killed by the turbines.The birds and bats being killed by the turbines are larger and are birds of prey. Many are on the endangered species list. The reason these birds fly around the turbines is they are gliders looking for prey in the open fields. Have you every head of a cat capturing a raptor?Shouldn't we be asking how may cats raptors kill each year?Once you look at the facts the story is quite different.

author: Gyro
author_rank: Super Contributor
timestamp: October 04, 2020, 07:10:46 pm
content: This discussion has gone downhill to evil little pampered b*stards killing indiscriminately for the fun of it (I mean the cats!) faster than I expected.There are no bats within miles of offshore wind farms and their siting is done with very careful consideration and public review of their environmental impacts - on wildlife (airborne and marine), fisheries, risk to shipping movements and aesthetics when viewed from the shore etc. That's the case for the UK ones (I assume other countries use the same procedures, I don't know about the US).

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 04, 2020, 10:31:56 pm
content: Quote from: tom66 on October 04, 2020, 06:09:23 pmSolar uses much less wiring - just the little bit to connect the panels to the building it serves.

author: KE5FX
author_rank: Super Contributor
timestamp: October 04, 2020, 11:14:31 pm
content: 60+ GHz automotive radars would be good for detecting approaching birds, given that turbines need a wide-open area in order to operate. I wonder if birds would veer away from the blades if you hit them with a low-power laser,a laNathan Myhrvold's mosquito zapper.Bats could probably be discouraged simply by making a lot of ultrasonic racket in the vicinity.Cats can be discouraged by keeping them indoors where they belong.

author: Cerebus
author_rank: Super Contributor
timestamp: October 05, 2020, 12:00:16 am
content: Painting a single wind turbine blade black cuts bird strikes by 70% (https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.6592). By the way, the study ran for 10 years and included proper controls.A tin of black paint is a bit cheaper than 60GHz radar sets and a battery of lasers.

author: KE5FX
author_rank: Super Contributor
timestamp: October 05, 2020, 12:18:01 am
content: Quote from: Cerebus on October 05, 2020, 12:00:16 amActually, I seriously doubt that. Durable outdoor industrial-grade paint is expensive these days, and most people have no idea how big those blades really are.Would you even need more than one laser and gimbal? It'd depend on whether entire flocks tend to get minced versus one bird at a time. No idea, but that question is probably what would determine the cost-benefit crossover point versus paint.

author: Cerebus
author_rank: Super Contributor
timestamp: October 05, 2020, 12:53:11 am
content: Have you not considered that the blades need painting in the first place anyway. It's just a change of colour. And of course, this now counts as a proven technique, which we can't (yet) say about your speculations. Plus paint is pretty reliable, I doubt the same could be said about a laser targetting system stuck up a pole somewhere, by definition, very windy and exposed.Before you start discussing cross-over points, you ought to first establish that your putative technique even works at all.

author: KE5FX
author_rank: Super Contributor
timestamp: October 05, 2020, 02:11:28 am
content: Quote from: Cerebus on October 05, 2020, 12:53:11 amIt's not 100% clear that the blades have to be painted, or that it's a good idea to do so.A few years ago, American Airlines boasted about saving weight and cost relative to its competitors by minimizing paint coverage on their airplanes.One sourcesays that the paint on a 737 weighs 555 pounds and costs over $100,000 to apply. It wouldn't surprise me if the blades on a typical wind turbine have just as much surface area as a passenger jet. Whether they need to be painted at all, I have no clue, but there's certainly an incentive to leave them unpainted if it doesn't hurt anything.QuoteHappy to try, but not for free.Idle speculation, of course, is always free, and worth what you paid for it.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: October 05, 2020, 03:46:41 am
content: I certainly hope that newer generation wind turbines have longer lives than those currently installed. I have driven the I-10 East of Los Angeles several times a year for the last 50 years and have watched the wind farms there develop over time. From the first experimental turbines (that literally fell apart in just a couple of years), through the installations of fields of ever larger turbines.One thing is obvious - the economic operating life of these things is quite short. There are whole fields of older turbines not operating. And even in the newest fields a surprisingly high percentage are not running even though others are clearly on line. I don't know the specifics of what causes this, whether it is actual wear-out of the turbines, shut down because safe operation can't be guaranteed due to fatigue life limits, end of incentive contracts or any number of other causes. But it is hard to see how this trend will turn into a long term energy solution. The argument that the newer units are much more efficient seems inadequate. If the original installation made economic sense it would seem to be worth continuing operations and trying to recover more of the sunk costs. Obviously the newer units are more profitable, but in that particular area they haven't covered all of the desert. There is no need to remove the old units to install newer and better ones.

author: f4eru
author_rank: Super Contributor
timestamp: October 05, 2020, 05:36:11 am
content: Could we use the old fiberglass material, sawing it into tiles, to do roofing ?

author: DougSpindler
author_rank: Super Contributor
timestamp: October 05, 2020, 08:17:35 am
content: @CatalinaWOW I know exactly where you are talking about. I live in the Bay Area where they installed nearly 5,000 in the Altamont pass in the highway 580/5 area. They decommissioned 25% of the turbines. Then out in the Delta they must have 5,000 or so turbines out there. Don’t know very much about that wind farm.The Altamount Pass wind farms was one of the first. This is where they discovered endangered birds and bat were being killed in large number. When the study was first completed a judge ordered the turbines not to spin to protect the endangered birds.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 05, 2020, 10:49:53 am
content: In Germany the time span the wind turbines got the extra money for the electricity was 20 years. With that number this was a clear target for the design. It may be a good compromise anyway as the technology is still improving. The newer turbines are not much more efficient - they are mainly get larger with the costs not going up as fast. Materials have also improved to get less maintenance cost. Getting more mature chances are the life time can increase. The blades may be still limited as heavier blades cause more wear.In theory they can reuse the foundation and often also the tower, but often they build new larger ones instead, as the old turbines were at the best spots and these are rare - at least in Germany. So they may remove 3 old ones to build one larger new with a higher power.AFAIK a common way of recycling the fiberglass is burning in the process of cement fabrication. The resin is used as fuel and the glass (silicate) part is a wanted ingredient to the cement. One could consider it a wast of material, but no real need to burry on a landfill - chances are the old blades still have an economic value.The larger the turbines get, the less birds and bats are hit, as less of them fly so high regularly. It's not just turbines and cats that kill birds - collisions with cars also kill more birds than wind turbines, at least in Germany.

author: gmb42
author_rank: Frequent Contributor
timestamp: October 06, 2020, 10:51:47 am
content: Clean energy is cancelling gas plantsApparently, by following the money, the analysts are seeing investor demand for gas plants decreasing, even in the land of maximum fossil fuel usage.I don't know, but suspect that the Rocky Mountain Institute is somewhat of a cheerleader for renewables though.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 06, 2020, 11:13:16 am
content: First time I have ever seen a unbiased news article to end say to take action and make a donation?TAKE ACTIONJoin us to answer the global call for a brighter energy future

author: Cerebus
author_rank: Super Contributor
timestamp: October 06, 2020, 02:56:24 pm
content: You haven't read many mainstream newspaper's web sites recently then. Just about every newspaper website asks for money now, some as donations some as subscriptions, it's hardly surprising that a non-profit's website does.In this day and age of dwindling newspaper circulation the money needs to come from somewhere, you are just faced with the choice of paying to see reporting on subjects that interest you, or reading something that someone else has paid for in an effort to influence you. Sadly we have reached the point where if someone isn't asking for money you need to ask the question "who paid for this"; so in general an appeal for donations is a weak indicator of a source that's more likely to be even-handed in their reporting or at the very least that you know what their agenda is. Getting from there to the truth is just a matter of using the uncommon "common sense" and its equally rare cousin, critical thinking.That just leaves the question of inherent bias. I've always known that the Daily Mail would cheer the fascists along, the Guardian was a bit lefty, and the Telegraph was written by and for mainline members of the Tory party and their camp followers - and so on. About the only paper news source I ever read that I was confident wasn't putting an idealogical spin on things was New Scientist. In the world of "Nu Meija" guessing the allegiances up front isn't as easy a task as it was with a long published newspaper. Reading any reporting without your mental spin filter in place is a act of intellectual self-vandalism.

author: ahbushnell
author_rank: Frequent Contributor
timestamp: October 06, 2020, 02:57:59 pm
content: Quote from: NiHaoMike on October 04, 2020, 10:31:56 pmNot in a solar power plant.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 06, 2020, 03:23:46 pm
content: PV installations usually need quite a lot of cabling between the panels. For the rest it depends: it can be relatively little for a small roof top installation if the normal house installation is large enough. Already with larger building, e.g. farms the normal electricity demand may be way smaller than the possible PV installation and they may need extra cables.Usually PV has a relatively low energy output compared to the installed power. Wind power is often better in this aspect: in Germany it's roughly 10% for PV and some 25 % for on shore wind and some 50% for off shore wind. So PV can cause more stress to the grid, though also more predictable. A mix has some additional benefit, as high wind often comes with clouds. The comparison also depends on the location for both sun and wind.

author: SparkyFX
author_rank: Frequent Contributor
timestamp: October 06, 2020, 06:21:52 pm
content: Quote from: DougSpindler on October 04, 2020, 04:22:15 pmFound that one interesting:https://www.bbc.com/news/science-environment-53909825It is kind of interesting, the first turbines i saw had red markings on the blades, might be that leaving that away was a bad decision.

author: elekorsi
author_rank: Regular Contributor
timestamp: October 12, 2020, 08:51:12 am
content: For me, one of the biggest problems in renewable energy sources like PV and wind turbines is its effect on the reliability and stability of electric grid. There is a fine line of how much of these sources can be used in the whole grid. The most obvious problem are of course weather conditions which affect the productivity the most...Another problem, that is not mentioned usually is the importance of rotating mass in the grid. At suden spikes a lot of compensation is done by large turbines and generators in thermo and hydro power plants, due to its inertia. Of course PV has none of it, but one would say that the wind turbine has a lot of it... not really, since it is feeding the grid via an inverter.The problem in the clean energy propaganda is, that almost no one talks about its effects on the power grid.Good, stable grid must consist of different sources. Big thermo power plants (for me the thermonuclear is the only good solution currently) running constantly at max power, smaller power plants for power regulation (hydro or gas powered), standby - on demand power plants that provides power at larger demands and unexpected shutdowns of larger power plants and of course the renewable energy sources like PV and wind turbines. More renewable sources also mean more on demand power plants. Nice and clean example of on-demand power plant is accumulating hydro power plant which pumps water to higher elevation when there is too much production in the grid and uses this water for generation when it os nedeed. Also it can be standby gas powered (we have one in our country) but it has quite big operating costs, as it is constantly heated, spinning at low RPM without load and allways ready to spin to rated RPM and accept the load in seconds.Everyone would drive an EV, cook on induction, use their AC, heat their homes with heat pumps, etc. and of course with the electricity generated 100% from renewable sources. It is not going to work!

author: AndyC_772
author_rank: Super Contributor
timestamp: October 12, 2020, 09:55:48 am
content: We had solar PV panels installed on the roof a few weeks ago, 16 panels each rated at 365W under some best case test conditions.With direct sun, in the middle of the day, we get 5kW after conversion losses even here in the UK in October - enough to power our own home and several others. I was really pleasantly surprised.However...- The moment a cloud moves in front of the sun, that can easily drop to 1kW or less; the difference is enormous. On a day with patchy cloud, the power output is effectively on / off every few minutes.- In the morning and evening, when the sun is low in the sky and there's shading from nearby trees, we get a few hundred W at best.- It's quite rare that peak availability of solar output coincides with peak demand. In the morning we're using the kettle and coffee maker before there's any meaningful solar output, so they're still powered from the grid. In the evening the relatively light loads like the TV, lights and computers run from batteries that were charged from solar during the day, but the large peaks (cooking etc) still need the grid.Overall, the solar panels do meet most of our demand for electricity on reasonably sunny days. On cloudy days they're nowhere near, and there's really no correlation between demand and availability. I dare say the same is true for wind power; plenty of it around in total, but no correlation between availability and demand.To have any hope of being effectively independent of the grid, we'd need more panels - but also alotmore batteries. We have 4.8kWh right now and we'd need at least 2-3x that capacity to have a hope of not drawing on the grid for heavy loads or early morning use.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 12, 2020, 10:44:56 am
content: For the wind turbines it depends on the type of generator if there inertial is part of the rotational mass or not.There are different generator types, some with an inverter for the whole power and some with with an inverter only for regulation of the generator excitation (a little like the generator in the car, but AC). For a very short time there are also capacitors in the PV inverters - so for a few ms they can also buffer.PV and wind give extra stress to the grid, but on the long run gas and coal are not an alternative. The clouds on the local PV system are not so much of a problem, as this is a very local effect, so it could be already a few houses down the street that the cloud comes later. So while PV is distributed generation it still needs the long range grid to flatten the fluctuations.The first 25-50% renewable are the easy part - the tricky part comes when we also need extra storage.Nuclear power turned out to be rather expensive - meanwhile even PV got a lower price in not so good positions. If taking it seriously nuclear is also not dependable: For safety reasons one should be ready to turn them down if a flaw is found (e.g. like the flaw in the RMBK that was part of the Chernobyl disaster or the weakness in cooling after a power outage found in the westinghouse type BWRs found in Fukushima). So you have to choose between safe and dependable.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 12, 2020, 02:49:05 pm
content: What about 30% from renewable sources and the rest from nuclear?

author: Kleinstein
author_rank: Super Contributor
timestamp: October 12, 2020, 03:10:41 pm
content: Quote from: DougSpindler on October 12, 2020, 02:49:05 pm70% nuclear would be a problem for several reasons: it would be pretty expensive. Unless one would cut down on electricity a lot, it would take a long time to build new capacity, so what to do in meantime (e.g. some 30-100 years). In the long run Uranium would get expensive too if done on a larger scale - breeder reactors tend to be even more expensive than conventional ones.Nuclear power may also have trouble to work with other flexible sources and one would have too much power at night. Not running most of the nuclear at night would increase the costs even further. So like with PV or wind it becomes a problem if more than some 25-50%. France already has the problem of excess power at night and short on peak power in summer if a few of the nuclear stations lack cooling water or in winter when demand peaks. Like the renewable nuclear power on a large scale needs additional storage and flexible power / backup. There is also no insurance against the need to turn them all down, if a problem turn up. So maybe keep the existing 3-10% nuclear, but why build new if wind / PV with battery storage is similar to lower price but lower risk.

author: Cerebus
author_rank: Super Contributor
timestamp: October 12, 2020, 03:19:55 pm
content: Quote from: DougSpindler on October 12, 2020, 02:49:05 pmDoesn't work because of the disparity between different generation method's ability to pick up load as demand changes. Nuclear takes ages to spin up and down, but is completely predictable in capacity. Renewables, at least wind and solar, have unpredictable capacity so can't be turned on and off to meet demand. You need something to bridge the gap which has predictable generation capacity and can be brought online and taken offline quickly as load changes - so storage (battery or stored hydroelectric), or fast spin-up/spin-down like open cycle gas turbine. All of those are either relatively short term, or inefficient (open cycle gas turbines) so you need something intermediate to fill in between base load nuclear, fickle solar and wind, and fast reacting but limited capacity stored energy systems. That leaves you with closed cycle gas turbines (including biogas, but there's little of that as yet) and older dirtier generation methods such as coal and diesel.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 12, 2020, 03:35:51 pm
content: I’m in California and we just like Arizona have days where we have excess solar electricity. PG&E pays other power companies to take it. We are tapped out on hydro electric. There just aren’t anymore places where hydro-electric can be installed.So what’s left?

author: coppice
author_rank: Super Contributor
timestamp: October 12, 2020, 03:50:35 pm
content: Quote from: AndyC_772 on October 12, 2020, 09:55:48 amYou must have those panels inclined at a very optimal angle for the time of year. 365W x 16 = 5.84kW. Allow a reasonable percentage for losses, and your 5kW is about the highest you could possibly get.

author: Cerebus
author_rank: Super Contributor
timestamp: October 12, 2020, 03:56:08 pm
content: Quote from: coppice on October 12, 2020, 03:50:35 pmAnd/or time of day. I've often wondered if sun tracking for rotation and angle would be worth it for a domestic PV system, but not with enough curiosity to sit down and actually calculate the costs/gains. Obviously it'd only be useful if you've got the 'farmer' type PV, using up the corner of a field, it wouldn't be practicable for a roof top system except on a big flat roof.

author: AndyC_772
author_rank: Super Contributor
timestamp: October 12, 2020, 04:56:54 pm
content: Quote from: coppice on October 12, 2020, 03:50:35 pmIt's pretty close; it's a south facing, pitched roof, and the fact that COS x ~= 1 for small values of x means the angle doesn't have to be perfect in order to get close to maximum output.Re: conversion losses, the inverter is remarkably efficient and I doubt the cabling loses too much either given that it's carrying no more than 10A even in full sun.https://www.fronius.com/en-gb/uk/photovoltaics/products/home/inverters/fronius-primo/fronius-primo-5-0-1: it may be that the inverter is capping output at 5kW since that's its output rating - it's not clear from the data sheet whether it can handle greater power for short periods, or whether it reduces the panels' output to keep within its own output rating.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 12, 2020, 05:35:56 pm
content: Quote from: Cerebus on October 12, 2020, 03:56:08 pmFWIW, in my last job I had a good deal of direct contact with power generation and power systems engineers. About 10 years ago, they were already saying that tracking systems were less economical than adding more panels. Tracking systems are mechanical systems with bearings, motors, and electronics, and must be strong to withstand wind loading. Ones that last as long as the panels are very expensive, maintenance is expensive, and reliability is poor compared to additional panels. You don't even save much space, because with a tracking systems you must keep panels farther apart to allow for movement and to prevent shadowing. They had actually had installed systems and gathered data on this, since at the start of the study, it was less clear.I find this debate somewhat funny. Power companies and utilities started voting with their dollars (or your favorite local currency) years ago. They are used to thinking long term and put a lot of resources and staff into understanding the total cost of energy. Does that mean they are perfect, or that the world circumstances will never force adjustment of model inputs? Of course not, but most of them are very good at it and the models are not static. They also don't tend to publicize what they know because this understanding and expertise is extremely valuable and thus proprietary. Giving it away would be cause for termination of employment.Also, if you are going to argue about bird losses, please take the numbers of birds lost to coal, natural gas and other sources into account. Make sure to include the effects of mining and transporting fuel. At least, please do so if you actually care about birds. Maybe consider some other forms of wildlife, as well. If you are really interested in this topic, you might be interested to know that one of the main measures of ecosystem health is the Shannon Diversity Index, yet another application of Claude Shannon's work on information theory. It can help you reduce favoring one bird, or species, over another.Cheers,John

author: Cerebus
author_rank: Super Contributor
timestamp: October 12, 2020, 05:52:47 pm
content: Quote from: JohnG on October 12, 2020, 05:35:56 pmI had suspected that it would be a close run thing but, as I said, was too lazy to do any calculation because, as you point out, it isn't just the simple cost of a few motors versus a few percent in PV efficiency. From my point of view a helpful answer, consider my curiosity satisfied. Thank you.QuoteOne caution I'd sound about adjudging an answer from people 'voting with their dollars' is that the whole thing gets confounded by the regulatory environment, incentives or disincentives set up by governments and, in some environments, the massive lobbying efforts made by people with their own interests to protect/promote. There's an engineering answer, and there's an answer that has to deal withrealpolitik- I suspect people here are interested more in the engineering answer than in one served with a bitter side dish ofrealpolitik.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 12, 2020, 06:19:13 pm
content: For the classical Si based solar cells there is not much use in moving them around. It is just cheaper to use the flat area and have a few more panels. A tracking system would need quite some space in between to avoid one part giving shade to the neighbor. So a tracking system would need more total land area.Tracking can still be attractive with other systems, that get better efficiency or thermal storage from concentrated light. This can be special PV cells or thermal systems. There is especially the 1 D tracking with the parabolic mirror technique. The balance also depends on the climate, as concentration only works well with a clear sky.

author: coppice
author_rank: Super Contributor
timestamp: October 12, 2020, 06:33:18 pm
content: Quote from: JohnG on October 12, 2020, 05:35:56 pmI've seen dynamically tilting installations. They look OK, but are costly and only really practical for ground level installations. I've seen full sun following installations. They seem self defeating. They need so much extra space around each panel to avoid shadows on adjacent panels it looks like they'd get more output by just filling more space with fixed panels. In the end they look more like a rich man's plaything, than a serious energy production facility.

author: hendorog
author_rank: Super Contributor
timestamp: October 12, 2020, 06:55:13 pm
content: Quote from: AndyC_772 on October 12, 2020, 09:55:48 amInterested to know what percentage of the total cost of the system went in the generating component - i.e. the panels?I'd guess about 33%, but you have batteries too so it might not be that high.

author: AndyC_772
author_rank: Super Contributor
timestamp: October 12, 2020, 07:28:16 pm
content: I couldn't really say; we had a single quote for the complete system including inverters, batteries and installation.

author: f4eru
author_rank: Super Contributor
timestamp: October 12, 2020, 09:14:57 pm
content: Quote from: DougSpindler on October 12, 2020, 02:49:05 pmThat doesn't work any more.It's too expensive because nuclear costs >3x more than renewables.It's not really flexible.It would be much more expensive if used flexibly.Let alone all the small issues like we cannot get rid of the wastes.The only reason to still plan to use nuclear power in 2020 is to make bombs.The thing the modern energy based society needs is scalable seasonal electricity storage. Hydrogen from electrolysis + fuel cell would be perhaps a borderline acceptable solution to that problem.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 12, 2020, 09:45:56 pm
content: Where does the electricity come from when the sun isn't shinning and the wind isn't blowing and we don't want to burn anything? Doesn't that leave nuclear?

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 12, 2020, 11:27:30 pm
content: There's hydroelectric power and OTEC. And then there's adapting load to better match supply.

author: elekorsi
author_rank: Regular Contributor
timestamp: October 13, 2020, 04:57:13 am
content: Sory, but nuclear is more friendly to the enviroment then hydroelectric, which are really a big problem for the rivers ecosystemQuoteReally??

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 13, 2020, 05:24:20 am
content: There's damless hydroelectric that (as its name implies) doesn't have the problems caused by dams, but that's really only useful for near constant load.

author: james_s
author_rank: Super Contributor
timestamp: October 13, 2020, 05:44:41 am
content: I'm a cautious proponent of nuclear. It is not without problems, but neither is any other adequate source of energy. An ironic result of the anti-nuke movement is that we have a lot of really old plants still operating rather than being replaced with newer, safer and more efficient nuclear plants.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 07:33:58 am
content: Nuclear has a far better environmental, health and the lowest death rate of all of the other energy sources. Comparing coal with nuclear. The environmental damage called by nuclear is next to nothing compared to coal. All of the deaths which have occurred in 60 years of nuclear energy is about the same as one small coal mining accident. And as for the health hazards, coal is far worse than nuclear.Once we figure out fusion our energy problems will be solved. A Chernobyl scale accident with fusion will have decayed away in 15 - 20 years and there is no long term nuclear waste.

author: f4eru
author_rank: Super Contributor
timestamp: October 13, 2020, 11:42:40 am
content: hmm. No.Nuclear usually kills over million of years, when the waste leaks out to the water table. -> much much much more to come.Coals kills only during use, yes.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 12:10:34 pm
content: Quote from: f4eru on October 13, 2020, 11:42:40 amThink again. Coal has killed tens of thousands of miners. The burning of coal releases radioactive elements into our atmosphere. Th slag heaps are radioactive. Mine tailings and slag heap accidents have killed tens of thousands. Then you have all of the respiratory health issues millions suffer from when coal is burned. Then the burning of coal affects everyone on the planet with the real ease of greenhouse gasses.Current nuke technology is far better for us and the planet.But next gen nuclear can’t kill over millions of years, the half-life is way too short. The worst accident will only kill for 8 years. After 20 years, it will have decayed away.What’s not to like about next gen nuclear?

author: Galenbo
author_rank: Super Contributor
timestamp: October 13, 2020, 12:38:11 pm
content: Quote from: DougSpindler on October 12, 2020, 09:45:56 pmNo Nuclear doesn't react that fast.It will be Coal and Gas that produces at that moments.And stays in expensive and polluting standby modus when there is wind&sun.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 13, 2020, 12:56:46 pm
content: Automated load management would probably be the "greenest" solution.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 13, 2020, 01:41:14 pm
content: Quote from: DougSpindler on October 13, 2020, 12:10:34 pmWhat's wrong is that I have been hearing about it almost as long as I have been hearing about fusion. I was once a big proponent of this, but so little progress has been made that is has been very disheartening.John

author: themadhippy
author_rank: Super Contributor
timestamp: October 13, 2020, 03:01:05 pm
content: Nuclear's not much use if your on uncle sams naughty list

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 03:11:32 pm
content: Quote from: Galenbo on October 13, 2020, 12:38:11 pmFrom what I understand coal doesn’t react that fast either.As for diseases coal causes, I forgot to mention black lung disease.Not aware of anyone dying from leaking nuclear waste, but fracking is sure causing issues.

author: coppice
author_rank: Super Contributor
timestamp: October 13, 2020, 03:24:36 pm
content: Quote from: DougSpindler on October 13, 2020, 03:11:32 pmCoal and traditional nuclear generators are much slower to run up and down than gas powered generators. However, a lot of the newer reactor designs would be much more responsive to changing demands. To make small modular reactors, suitable for powering an isolated community, responsiveness is a prime design consideration, as the generator is unlikely to be on a grid.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 13, 2020, 03:33:09 pm
content: Quote from: DougSpindler on October 13, 2020, 12:10:34 pmThere are two big problems: 1st. It would take at least 50 years to develop, likely longer, just like fusion. So it would not be ready in time and we need another solution first. 2nd the promises about only short time wast just don't work, not even in theory: there are just not enough neutrons to do all the transmutation. Another problem with transmutation is it need huge amounts of chemical separation, so it gets very very expensive and may need more energy than produced in the first place. So if one does the math the result is it just does not work - hardly any noticeable reduction in the waste.What you here from next gen nuclear are usually best case assumptions - far from realistic, it just can't get better than that. A breeding reactor is tricky to operate, as the usual intrinsic safety mechanisms cause a loss of neutrons - so these reactors are usually more tricky to operate. They would be lucky if they get it as well behaved as the RMBK that caused the Chernobyl disaster.With using thorium, there is one important drawback often ignored: to get breeding, one needs very pure thorium and relative frequent chemical cleaning of it. This makes it prohibitive (orders of magnitude to expensive) to reuse the thorium. So one would not use some 98 % of the thorium as usually claimed, but more like 0.1-1 %. So thorium is.The chemical separation was essentially stopped by the US because of nuclear proliferation risks. Essentially all next gen. nuclear ideas include some for the chemical reprocessing.In many places the dangers from nuclear waste are exaggerated - it may be highly radioactive now, but in some 100 years the activity is already down by some 95-99% (depends on were to start counting). Because of the mixture of isotopes the decay is much faster in the initial phase and slows down later. The safe disposal of the waste is still not easy and cheap.Nuclear may be better than coal, but it is still not good enough.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 03:53:04 pm
content: If what you are saying about Next Gen nuclear is correct why was NIF built? And why have the experimental results disprove the math you mentioned? Why is ITER being built if next gen nuclear doesn’t even work in theory?What am I missing?

author: f4eru
author_rank: Super Contributor
timestamp: October 13, 2020, 03:56:05 pm
content: Quote from: Galenbo on October 13, 2020, 12:38:11 pmExactly.I think it will be more "Gas and gas", as it seems now, coal plants being converted to gas, or closed altogether.In the long run, as soon as viable seasonal storage will become feasible at scale, those plants will quickly disappear also.

author: VooDust
author_rank: Regular Contributor
timestamp: October 13, 2020, 03:56:40 pm
content: Quote from: tom66 on October 04, 2020, 05:08:59 pmExactly this.

author: f4eru
author_rank: Super Contributor
timestamp: October 13, 2020, 04:02:20 pm
content: Quote from: DougSpindler on October 13, 2020, 03:53:04 pmThose are fundamental research facilities, not even trying to solve an energy problem.Iter is just a boondoggle, and will fail to demonstrate much more than a minute runtime, because of plasma instabilities causing breakdowns.It's just like trying to hold down a hungry tyrannosaurus with your bare hands.

author: Cerebus
author_rank: Super Contributor
timestamp: October 13, 2020, 04:13:48 pm
content: Quote from: DougSpindler on October 13, 2020, 03:53:04 pmThe difference betweenfissionandfusion.The next generation nuclear people are talking about are newfissionreactor designs. Ideally designs that are intrinsically safe, producerelativelybenign waste products and cannot be used in the proliferation of nuclear weapons.NIF, ITER and all that is about trying to work towards creating practicalfusionreactors. So far fusion reactors are teetering on the point of getting out slightly more energy than is put in. They are, as yet, a long way from a practical source of power.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 05:23:57 pm
content: Fusion is what's providing the source of energy for solar, wind and hydro right now. It has been demonstrated we can do it. In addition to NIF there are 5 other companies working on it. They are getting net positive energy... So it is possible.

author: Cerebus
author_rank: Super Contributor
timestamp: October 13, 2020, 05:32:25 pm
content: Quote from: DougSpindler on October 13, 2020, 05:23:57 pm

author: coppice
author_rank: Super Contributor
timestamp: October 13, 2020, 05:37:36 pm
content: Quote from: DougSpindler on October 13, 2020, 05:23:57 pmWhere did you get that idea? NOBODY has achieved net positive energy from any form of controlled fusion. There are examples of instantaneous net positive results, but not an overall net positive. So much energy has been needed to bring the system up to the brief periods of output that have been achieved. The whole point of ITER, the Wendelstein 7-X Stellerator, and other current projects is to build on the results of things like JET, and try to achieve real net positive energy and a much more sustainable reaction.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 05:38:22 pm
content: NIF

author: coppice
author_rank: Super Contributor
timestamp: October 13, 2020, 05:46:42 pm
content: Quote from: DougSpindler on October 13, 2020, 05:38:22 pmWhere have you seen NIF claim a net positive energy from their facility? Not a half baked headline, but a proper claim. All I have seen is statements like "during an experiment last month, the amount of energy released through a fusion reaction exceeded the amount of energy being absorbed by the fuel.", which sounds like a properly worded statement, but isn't net positive energy at all.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 06:06:06 pm
content: They had an open house about a year ago and that's what I was told. LLNL seems to be very cautious about publicity.Haven't a couple of the private companies reached energy parity? Just haven't crossed over to net positive?

author: james_s
author_rank: Super Contributor
timestamp: October 13, 2020, 06:34:01 pm
content: Quote from: JohnG on October 13, 2020, 01:41:14 pmI think most of the reason for that is not technological but political. Nuclear is no longer politically correct, and any sort of development gets stalled and issues like transporting waste through various areas gets a lot of pushback. It ends up being easier to just keep patching up the old plants and keep them running while waiting for some new super green unicorn technology to save the day.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 13, 2020, 07:49:42 pm
content: One of the most politically incorrect things about nuclear is its very high capital cost and low return on investment. Politicians will hate you for this.John

author: f4eru
author_rank: Super Contributor
timestamp: October 13, 2020, 10:00:55 pm
content: And the even bigger elephant in thee room: Cleanup costs further down the timeline that haveneverbeen factored in, which will multiply the cost of that energy by 2.As said previously: with double the cost, the only reason to plan nuclear power in 2020 is to make bombs.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 11:09:00 pm
content: Quote from: f4eru on October 13, 2020, 10:00:55 pmWhy is it we clean-up after nuclear but not hydro-electric, coal or gas? Any idea how difficult it is to make a nuclear bomb? It's not that easy.

author: themadhippy
author_rank: Super Contributor
timestamp: October 13, 2020, 11:17:57 pm
content: Quotebecause thats the american way?meanwhile here in the uk many old coal fired power station are now or will soon be housing estates.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 13, 2020, 11:26:15 pm
content: Quote from: themadhippy on October 13, 2020, 11:17:57 pmI just watched a video about the nuclear power plant that was turned into an amusement park in the Netherlands/German/Belgium border.That's because you've run out of land. In the US we still have a lot of land we can leave our garbage on.

author: BrianHG
author_rank: Super Contributor
timestamp: October 14, 2020, 12:17:49 am
content: Just so FN we are clear about the stupid '500K bird loss'.QuoteGo remove every sky-scarpers on earth first, then worry about the windmills puny number of deaths which can be even significantly lowered just by making the blades black.Do you know how many birds as well as wildlife has been destroyed by our Alberta tar sands alone here in Canada in the name of Big Oil.I'll take any good tech which gets us off the oil/fossil fuel craze as soon as possible, even if we need to pay a little premium in the beginning. Windmills are a valid portion of that solution.

author: themadhippy
author_rank: Super Contributor
timestamp: October 14, 2020, 12:33:24 am
content: Quotefunny you should mention rubbish,just watched a uk program called mega shippers and it turns out the uk is shipping waste, that normally would go into landfill, to Sweden were its burned for electricity generation and district heating .A bit of research and it turns out the uk is paying for the waste to be removed ,its cheaper than the taxes to bury it.Its not green energy ,but surely burning it in the uk would save on both emissions and the transport cost,or maybe thats too sensible/not enough brown envelopes for the british government

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 12:43:38 am
content: Quote from: themadhippy on October 14, 2020, 12:33:24 amDo you know what's happening to eWaste? Thanks to the world sending their eWaste to Ghana to be burned, and the British providing high speed Internet to the country we are all being scammed as we pollute another country.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: October 14, 2020, 02:00:37 am
content: How is e waste burned safely and economically? I know when my company tried to do it back in the 1990s it was ghastly expensive to control all of the emissions and residue. The amount of heat generated was no where near enough to pay for the process. We ended up getting out of the manufacturing business, letting someone else deal with it. Has someone solved the problem now, or is it just a little greenwashing of the necessary disposal expense?

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 02:15:45 am
content: Quote from: CatalinaWOW on October 14, 2020, 02:00:37 amDid you watch the video? Apparently the folks in Ghana have found a way. Not sure about the rest of the world, but in the US we pay an eWaste recycling fee. It's nice to what's done with all of that money that's collected.

author: boB
author_rank: Frequent Contributor
timestamp: October 14, 2020, 03:54:36 am
content: WTF = Wireless Transmitted Fusion (energy)Just need the receiving antennas to use this resource. Like PV panels or wind/water turbines.Just like Tesla envisioned. But this energy is free unlike his would have been and works over most of the earth instead of a short range from the transmitter.Fusion works pretty well if you have enough receivers. The transmitter is a long ways away.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 04:29:53 pm
content: Quote from: boB on October 14, 2020, 03:54:36 amTesla said a lot of things, including he had an electric car powered by the energy from the universe. He remove ICE motor and replaced it with his vacuum tube energy receiver. Like all of Tesla’s proposed inventions later in his life they never worked.

author: Nauris
author_rank: Regular Contributor
timestamp: October 14, 2020, 06:34:33 pm
content: Quote from: themadhippy on October 14, 2020, 12:33:24 amBut there is not that much need for the heat in the UK or district heating systems? If it were burned in the uk to make just electricity most of the energy is lost. If it is burned in Sweden to make mostly district heating it has some 95% efficiency. So it is actually much more environmentally friendly to ship it to Sweden and burn there because the energy content of the wastes can be utilized so much better.

author: james_s
author_rank: Super Contributor
timestamp: October 14, 2020, 06:42:02 pm
content: The UK is not exactly warm. I mean during the summer heat is not needed, but throughout probably 7 months of the year most occupied buildings will need to be heated. Not as much as in Sweden but it's not like they don't need heat.

author: Cerebus
author_rank: Super Contributor
timestamp: October 14, 2020, 06:56:58 pm
content: Quote from: DougSpindler on October 14, 2020, 02:15:45 amDoug, you've gotten into a habit of saying this. It's rather presumptuous to expect people to take time out watching 20 minute or longer videos because you can't be bothered to either make or summarise the argument yourself. Once in a while for something complex, it might be the only way, but you're a serial offender in this regard and I've already been involved in threads where to follow what you're saying would have required watching hours of video, much of it far from as good or conclusive as you've implied.

author: coppice
author_rank: Super Contributor
timestamp: October 14, 2020, 06:58:16 pm
content: Quote from: themadhippy on October 14, 2020, 12:33:24 amThere are numerous power stations around the UK that were built as waste disposal incinerators, with generation plant added on to make good use of the released energy. There is one beside the North Circular Road in North London. It became operational in 1969, and has provided good service since then. It has a tall chimney with lots of flue filtering, to minimise anything harmful in the exhaust it produces. Its nearing the end of its life now, so they need a new plant. Unfortunately, the NIMBY problem has come into play:https://www.hackneygazette.co.uk/news/environment/north-london-incinerator-project-cost-soars-to-1-2-billion-1-6422599

author: coppice
author_rank: Super Contributor
timestamp: October 14, 2020, 06:59:59 pm
content: Quote from: Cerebus on October 14, 2020, 06:56:58 pmI agree with you to an extent, but look at the other side. If someone hasn't watched the video, and doesn't know what arguments its making, why are they commenting?

author: themadhippy
author_rank: Super Contributor
timestamp: October 14, 2020, 07:10:25 pm
content: Quotedistrict heating isnt common in the uk,but the hot water could be used by new industrys built to take advantage of the cheap hot waterQuotegive them the choice,a nice compact waste burning plant , a nice shiny "non polluting" nuclear plant or local power cuts.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 07:14:49 pm
content: Quote from: coppice on October 14, 2020, 06:58:16 pmThese are complex topics and I have found people in the forums ask questions which are clearly explained in the video. I don't want the info I'm posted to be considered conspiracy theory BS which is why I provide links to the source material I am using for my information. That way the viewer can use their critical thinking skills to determine if what I'm saying is accurate or not.And something else.... If you watch the video don't you learn something you didn't know? I hope you agree learning is a life long experience. I can't begin to tell you how much I have learned from the good people in this forum and Dave's videos. I would think everyone posting in these forms is also here to learn.

author: coppice
author_rank: Super Contributor
timestamp: October 14, 2020, 07:19:27 pm
content: Quote from: DougSpindler on October 14, 2020, 07:14:49 pmI think you responded to the wrong comment, but there is a good reason why nobody since Thomas Young has been considered a polymath.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 14, 2020, 07:55:13 pm
content: Quote from: DougSpindler on October 13, 2020, 11:26:15 pmThat nuclear power station (Kalkar) was never running - it was an essentially complete build fast breading reactor. However because of some doubts in the safety, the expected high costs (seen with the French counterpart that started a little earlier) and lack of reprocessing it was never brought into service. So it was just a large robust concrete building, that got a new use.There is not much experience taking down real nuclear power plants. There is some with a reactor from eastern Germany: AFAIK the main part is dismantled and the parts are still waiting for a safe place for final disposal. The costs turned out relatively high - quite a bit more than originally planed for - more than the original planed costs for the construction. However the original costs estimates were notoriously low estimates anyway. Dismantling those reactors that experienced a significant accident scenario (even if nothing left the plant) is a different and more expensive case, as there can be much more contaminated concrete. If will definitely not be fun in Fukushima.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 08:23:57 pm
content: Quote from: Cerebus on October 14, 2020, 06:56:58 pmThese are complex topics and I have found people in the forums ask questions which are clearly explained in the video. I don't want the info I'm posted to be considered conspiracy theory BS which is why I provide links to the source material I am using for my information. That way the viewer can use their critical thinking skills to determine if what I'm saying is accurate or not.And something else.... If you watch the video don't you learn something you didn't know? I hope you agree learning is a life long experience. I can't begin to tell you how much I have learned from the good people in this forum and Dave's videos. I would think everyone posting in these forms is also here to learn.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: October 14, 2020, 10:38:06 pm
content: So Doug Spindler you publicly shamed me into watching the video. And were lying in doing so.The only thing in the video on burning eWaste is in the first couple of minutes, and it describes what I thought was happening, open burning of the carcasses and letting whatever burns off blow away in the wind. The video says that the narrator expects the poor folks doing this to get cancer from the process.The rest of the video discusses internet scamming and juju. Both interesting topics I am sure, but not what I set out to learn today and actually very little information I did not already have. Remember there is an opportunity cost to learning, and you just swindled me into learning two minutes of new information by watching a twenty minute video. Nothing about safe and economical burning of eWaste. I could have spent the time on an internet search and learned more and faster.I had been warned about you, but did not take the warning seriously enough.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 14, 2020, 11:44:51 pm
content: Quote from: CatalinaWOW on October 14, 2020, 10:38:06 pmI feel as if you are twisting my words into saying something I didn't say."I asked if you now what's happening eWaste?"Hopefully you learned from the video eWaste from the US, Europe and Australia is being sent to Ghana for recycling. How are they doing that? They are burning it and picking through it to build computers to scam the people who sent them the computers for recycling.Sort of ironic, isn't it. We pay to have our eWaste responsibly recycled by shipping it to another country. We are trying to clean our air, but since our eWaste is being burned that pollution is just comes back to pollute our world.The entire point of the video is here we are paying for the safe and economical recycling of eWaste and it's being used to commit cybercrimes against us. Appears you missed the entire point of the video.

author: Cerebus
author_rank: Super Contributor
timestamp: October 14, 2020, 11:59:41 pm
content: If you'd taken the time and trouble to write that before, poor old CatalinaWOW could have had 20 minutes of his time saved. As I said before, you've got form for directing people to videos that are rather content light. Videos that take 20 minutes to watch to find out what could have been read in 20 seconds. Please, take the five minutes to write so that 10s of us don't have to spend collective 100s of minutes watching rather thin content, it's not like you're exactly reticent about writing.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 15, 2020, 12:03:50 am
content: Quote from: Cerebus on October 14, 2020, 11:59:41 pmFair enough. Guess I'm still suffering from the conspiracy theorists who were posting disputes about nearly everything posted.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: October 15, 2020, 12:30:49 am
content: Doug Spindler I owe you a partial apology. I was contacting your comments with those in reply #74. But I still don't see how don't feel that "Apparently Ghana has found a way" misleading.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 15, 2020, 12:47:39 am
content: Quote from: CatalinaWOW on October 15, 2020, 12:30:49 amApology acceptedApparently Ghana has found a way" was meant to sardonic and ironic.Here we take great care to dispose of our eWaste properly and pay for it. Then we ship it to a poor country so they can burn it and pollute their beaches. And if that's not enough, they take our garbage and cyber-attack us with it.

author: Red Squirrel
author_rank: Super Contributor
timestamp: October 25, 2020, 01:52:15 am
content: To me I think we need to have a compromise. Why not try to find a material that is easier to recycle. Even if performance drops it's well worth it in the end if it means the environmental impact has been reduced even more.Either way though, the anti green energy people keep missing the whole point, that practically every project including fossil fuel related ones, have a life cycle that has a start and end environmental impact. The difference is the green energy ones ONLY have an impact at the start and end, while the fossil fuel ones have a continuous impact. Lot of indirect impacts as well throughout the entire life cycle such as the continuous need to mine, process, and transport oil product. So yeah we really need to solve the issue of recycling the wind turbines better but it's still better for the environment in the end than burning an equivalent amount of fuel that it generated throughout it's life time. While we're at it we need to figure out how to recycle nuclear waste... You never hear those people talking about that but yet they demonize solar panels and wind turbines.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 02:11:13 am
content: QuestIon is what is that material? I supple the we would be using it if we knew what it was. Don’t you think the ultimate solution is nuclear fusion? All of the material used to build the power station are recyclable or will have decayed away in 20 years. This is a wild guess but the footprint needed for one nuclear power plant would be the same 30,000 wind turbines. And nuclear power is produced at a constant rate.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 03:41:32 am
content: Quote from: DougSpindler on October 25, 2020, 02:11:13 amAnisotropic cellulose reinforced lignin composite? We made perfectly good propellers out of it in the past. I suspect people don't even consider it because it's "old fashioned" but if someone told me that a proper engineering analysis proved wood to be a perfectly adequate material I wouldn't be surprised. You can grow it, it's tough, strong, lightweight and recyclable.

author: schmitt trigger
author_rank: Super Contributor
timestamp: October 25, 2020, 04:32:20 am
content: The problem with nuclear is that, right now, is a political hot potato.Any elected politician, at any level in any country, advocating nuclear power would see his/ her political career dwindling faster than you could spell: “Nuclear Power.”

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 05:59:15 am
content: Problem with tress is they length if time need for that renewable resource to be renewed. England still hasn’t recover and it’s been a half century.I think the attitudes about nuclear are changing as they realize it is the best solution we have. Many of the environmental anti-nuke mouth pieces are dying and we are going though a period of generational amnesia of why nuclear was “bad”.

author: nctnico
author_rank: Super Contributor
timestamp: October 25, 2020, 09:04:21 am
content: Quote from: Red Squirrel on October 25, 2020, 01:52:15 amThere is nothing to recycle. Nuclear waste consists of toxic (heavy) metals. The only option is safe storage just like with any toxic material.Quote from: schmitt trigger on October 25, 2020, 04:32:20 amThat is no longer the case. For example: recently the Dutch parliament agreed to investigate building new nuclear power plants to see what the financial consequences are.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 09:50:47 am
content: With nuclear fusion the radioactive “toxic” waste decays away in about 10 -15 years. In 20 years it’s gone having decayed away. Isn’t this the solution we want? Unlimited fuel and no long lived toxic waste?

author: mzzj
author_rank: Super Contributor
timestamp: October 25, 2020, 10:03:57 am
content: Quote from: schmitt trigger on October 25, 2020, 04:32:20 amIn here we have one new nuclear power plant to start operation any minute now.. (has been like that for 12 years) and plans for another plant got political approval 5 years ago.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 25, 2020, 10:35:52 am
content: Quote from: DougSpindler on October 25, 2020, 09:50:47 amThere may be less radioactive wast with fusion, but it would not be so simple and good. Much of the radioactive isotopes can have a fast decay but there will also be some long lived ones, from other materials that got irradiated by the neutrons. It depends one the materials used to build the reactor. Which materials will be used and needed is still open - they sill need to develop the resilient materials to build the final reactor. Because of the very high demands on the material they may not be able to limit the elements used that much. So chances are one would also get some long time radioactivity, e.g. from Mo93 (4000 years half life) or Zr93 (1.5 mil. years). It would likely be less long lived radioactivity than with fission, but still very likely enough so that the building materials would need disposal as low to medium level radiative waste.Currently the research is at the point to check if the fusion is energetic feasible and it looks like is could. However there are more requirements: One needs to also to produce sufficient tritium to keep the process running. This is no totally clear and could be a deal breaker - at least it may requite compromises in other parts. Another point is getting a durable machine that can withstand the high neutron radiation for long enough to make it economic. It makes a big difference if the reactor can run for 10 years or only 6 months before the materials deteriorate from radiation damage.With fusion the result of the test reactors could very well be that it may work in principle, but is way to expensive with no realistic chance to become competitive.Form the tritium problem it is already clear the reactor would have to run a large part of the time, so it would produce quite some excess energy at night and would likely need storage.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 25, 2020, 12:46:42 pm
content: Quote from: Kleinstein on October 25, 2020, 10:35:52 amProbably the easiest part to solve, just make electricity cheaper at night.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 02:45:21 pm
content: Quote from: DougSpindler on October 25, 2020, 05:59:15 amWhatareyou talking about? Try visiting a lumber yard, anywhere in the world. There is not a shortage of wood.Quote from: DougSpindler on October 25, 2020, 05:59:15 amWhat do you think happened in Britain in 1970 that caused a shortage of timber that it's purportedly not recovered from? The only event noteworthy enough that one wouldn't name it and that happened 'half a century' ago, if one was severely arithmetically challenged, was the 2nd world war. Are you under the impression that the British Navy found the 2nd world war in these:I know that some Americans can sometimes be a bit parochial, but surely you couldn't believe that?

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 02:50:05 pm
content: Quote from: DougSpindler on October 25, 2020, 09:50:47 amThere are no practical fusion plants yet. There are no designs for practical fusion plants yet. Fusion power generation has been "twenty years away" all my life, I suspect that it will still be "twenty years away" for the whole lives of our grandchildren. It is, at the moment, a pipedream, not a practical solution.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 25, 2020, 03:13:09 pm
content: Quote from: Nihttps://www.eevblog.com/forum/Smileys/default/rant.gifHaoMike on October 25, 2020, 12:46:42 pmCheaper night rates for electricity has been the case for decades. The number of customers who can make good use of it has leveled off long ago.As for fusion, we have three categories of fusion right now. The sun, H-bombs, and controlled fusion research that is decades from being a viable energy source for billions of people. Only the first is a profitable energy source with proven scalability.Nuclear is expensive because even though the chances of an accident are small, the consequences are large. Companies in this situation gradually chip away at safety because nothing too bad happens and they are under constant pressure to make more money. When the feces hit the fan, the utility goes bankrupt and taxpayer gets the bill. Small nuclear sounds great, but it's been vaporware for decades. The money would be better spent on controlled fusion, because at least if it pans out, you might get something that will be a real breakthrough.Pro tip: Youtube videos are not a substitute for actual research by people who are actually working on the problems.Cheers,John

author: nctnico
author_rank: Super Contributor
timestamp: October 25, 2020, 03:38:35 pm
content: Quote from: Cerebus on October 25, 2020, 02:50:05 pmIt also depends on how much money and effort is thrown at it. Just look back at how quickly the Apollo program has been developed. My gut feeling says that if someone spends a trillion euro or dollars then they can have commercial nuclear fusion reactor running within 2 decades.

author: coppice
author_rank: Super Contributor
timestamp: October 25, 2020, 03:48:21 pm
content: Quote from: Cerebus on October 25, 2020, 02:50:05 pmThis idea that fusion is forever 20 years away is nonsense. When I was a kid in the 1960s people were talking about practical fusion generation some time in the next century. Maybe the middle of the next century. When they started building JET in the 1970s people were hopping for it to give us a good understanding of the detailed nature of the problem by the end of the century. It pretty much did that. Nobody expected that understanding to immediately lead to power stations. Fusion was always understood to be a huge problem with an uncertain outcome, but a problem with a potentially marvellous pay off if it can be solved.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: October 25, 2020, 03:49:27 pm
content: Cost arguments are funny things. People have been dreaming about solar electric since the 1940s or earlier. When real solar cells came along in the 1960s they only made sense where cost was no object, space and a few remote installations. Finally after six more decades of investment and innovation they make economic sense in a very wide number of cases.Saying something can't happen because of current costs is not a very solid position.

author: coppice
author_rank: Super Contributor
timestamp: October 25, 2020, 03:59:59 pm
content: Quote from: Cerebus on October 25, 2020, 02:45:21 pmThe problem the UK faced in the 70s was not a lack of wood. It was a lack of stockpiles kept long enough for the wood to properly season. After WW2 depleted stocks it was more profitable to import and rapidly use wood than to build a stockpile and give it time to be properly seasoned. So, we had lot of wood, at reasonable prices, but its quality was low.Try visiting a lumber yard in the UK today. Where are the massive stocks of reasonably priced mahogany? Where is all the oak? Where is anything but chipboard and MDF with a price that doesn't make your eyes water? There was lots of it in the 70s and 80s. Prices don't soar when there are plentiful supplies.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 04:04:35 pm
content: Quote from: nctnico on October 25, 2020, 03:38:35 pmPossibly. It depends whether the state of the art is at the stage where it's possible to speed it up by throwing more bodies at it, or the stage where throwing more bodies at it will slow it down (like a software project that's running late). I genuinely don't know which of those states we're in at the moment.Either way, we know that realistically nobody is going to throw that kind of money at it - only the US, the EU or China has the wherewithal (I doubt Russia has nowadays) and the governments of all those seem to have great difficultly finding their backsides with both hands at the moment, let alone launching the massive research project to end all research projects. If only we had solid proof of some looming disaster that could only be averted by the advent of practical fusion power, like an Alien invasion from outer space, that could persuade everybody to pull together to get it done like they do in the movies.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 04:24:58 pm
content: Quote from: coppice on October 25, 2020, 03:59:59 pmA complete red herring, on a completely tangential vector that just muddies and misdirects the conversation. Don't you have anything better to do than interject where your reply is generally a sweeping generalisation (frequently a misstatement representing some bit of history that you think you remember accurately but don't) followed by a hefty dose of "When I was a lad"?Funnily enough furniture grade mahogany and oak wouldn't be the materials of choice for engineering wind turbine propellers. Whereas engineered Baltic birch would - you know, the funny stuff they make good plywood out of. If you think that's in short supply you must be the only person in the western world who has never been dragged around Ikea by a friend or partner.And if you want to talk prices ("It's soooo much more expensive than when I were a lad"), make it relevant. Talk about the current price (not the 1970's prices) versus the current prices for carbon fibre, aramid fibre and epoxy resin for composites.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 04:26:42 pm
content: Quote from: coppice on October 25, 2020, 03:48:21 pm"Sweeping generalisation" followed by "When I was a lad...". See what I mean?

author: themadhippy
author_rank: Super Contributor
timestamp: October 25, 2020, 04:51:46 pm
content: QuoteThats all about to change in the uk,from 2025 no new builds will be permitted to use gas for heating.Meanwhile tougher rules on insulation for new housing have been quietly swept under the carpet,cant have us using less fuel leading to less profits for the energy firms now can we

author: coppice
author_rank: Super Contributor
timestamp: October 25, 2020, 05:05:56 pm
content: Quote from: Cerebus on October 25, 2020, 04:26:42 pmI described what serious people have ACTUALLY been saying about the prospects for fusion energy over my lifetime. The sweeping generalisation is this "its always 20 years away" rubbish.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 05:09:40 pm
content: Quote from: coppice on October 25, 2020, 05:05:56 pmYou said what you think you remember, yes, we get that.

author: coppice
author_rank: Super Contributor
timestamp: October 25, 2020, 05:10:48 pm
content: Quote from: themadhippy on October 25, 2020, 04:51:46 pmI suspect that 2025 thing will go quietly away. Nobody has a realistic plan for economically heating new homes without gas in that time frame, and nobody is going to buy a home with a crazy heating bill. I think it was a knee jerk reaction when someone was put on the spot one day.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 05:51:37 pm
content: In Berkeley California gas isn’t allowed in new construction. Heating has to be electric only. Seems crazy when gas prices are so low and electricity prices are so high. And with our power company lowering day time rates and increasing the rates in the evening it’s making it difficult for the people living pay check to pay check to stay in their homes. Berkeley has an enormous homeless population. With the increase in electricity rates at night to be 4 times day time rates people aren’t going to be able heat their homes. Solar in California is really screwing the poor people.

author: Cerebus
author_rank: Super Contributor
timestamp: October 25, 2020, 06:06:15 pm
content: Quote from: coppice on October 25, 2020, 05:10:48 pmI hope you're right. However, to mangle a popular quote: "Nobody ever went broke underestimating the intelligence of the political classes.".

author: james_s
author_rank: Super Contributor
timestamp: October 25, 2020, 06:11:28 pm
content: Quote from: coppice on October 25, 2020, 05:10:48 pmApparently it's already extremely difficult to build a house in Seattle with gas already. It's a stupid rule IMO, as gas is far more economical for cooking than electricity. A heat pump works pretty well for heating but for cooking and hot water, gas is the undisputed king. People will likely buy homes in the summer not even realizing that the heating bill will be high until they're settled in and the cold comes.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 06:22:28 pm
content: Gas is 3 times less costly than electricity. Except in California. With Time of Use pricing, gas is 10 times less expensive during the time of day when the rates are the highest. Staring in 2021 this will be at night.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 25, 2020, 07:01:41 pm
content: Quote from: JohnG on October 25, 2020, 03:13:09 pmAutomation technology will change that considerably, as will thermal storage.Quote from: DougSpindler on October 25, 2020, 05:51:37 pmThe Silicon Valley area has pretty mild winters so not much heating required. Thus the cost of installing and maintaining gas infrastructure would be largely offset by the limited savings it would provide. Not to mention the safety issues in case of an earthquake.Quote from: james_s on October 25, 2020, 06:11:28 pmNot as much as you think since a gas stove is only about 30-40% efficient while an induction cooker about 80-90%. Gas ovens are likewise less efficient since they cannot be sealed.Heat pumps work well for hot water, plus in the majority of homes, hot water is a thermal storage system that already exists, just needs a little automation to make it useful storage.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 25, 2020, 07:10:08 pm
content: Quote from: NiHaoMike on October 25, 2020, 07:01:41 pmEverything you are saying is correct, until you have to pay for it. Yes the winters are mild, but electric rates for peak are 10 times the price of gas. A heat pump is 3 times the cost. A gas stove during dinner hours is 10 time less to prepare the same meal on an electric stove.With the cost of living so high already, the old and the not so well off aren’t going to be able to afford the devices and electrical rates.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 25, 2020, 07:29:08 pm
content: On the long run we have to reduce the consumption of gas to keep the CO2 emissions in limits. Especially in the US this will likely be due to increasing costs (e.g. no more subsidies, higher costs, limits on production). So don't expect the price to stay this way for long. It may start to change as fast as next year.Even if politics does not intervene, chances are the boom of fracking gas may be over relatively fast. Just for cooking or hot water one does not need much gas and with rising temperatures the demand for heating is going down. It is more like one needs a heat pump for cooling in the summer and could use this also in winter.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 25, 2020, 11:06:44 pm
content: Quote from: DougSpindler on October 25, 2020, 07:10:08 pmWhat is the monthly service charge for natural gas over there? I wouldn't be the least bit surprised that over a year, the service charges would cost far more than the gas itself, negating the savings.As mentioned, because an induction cooker is 2-3x as efficient as a gas stove, it would not be 10x the cost. Also, heating and hot water can be scheduled to prefer off peak times, meaning the peak rates do not apply for those.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 26, 2020, 02:19:01 am
content: You keep overlooking as less gas is used it becomes cheaper as there is no market for it. What are we going to do with it if we don’t burn it? There was a time when gasoline/petrol was considered a waste product and dumped into streams and rivers to get rid of it. I wonder if that’s going to be the case with gas?Something else you are not factoring is that gas becomes free with solar in California. If at the end of the year you have an over production or surplus of electricity the utility company will convert that over production in to energy credits towards you gas bill.Another thing you are not addressing is the people. Yes induction might be 80% efficient. The energy to power an induction stove will cost the people 10 times more. Not to mention everyone would have to buy new cookware to work with an induction stove. And the cost for an induction stove is much more than a gas stove.Where is all of that money going to come from? If you are old and have a limited income chances are you won’t have the money to pay the higher electrical rates for electricity.If the goal is not to use gas why not raise the rates? I’m sure people will use electricity for cooking and heating - NOT. They will burn wood or use some other carbon fuel source to burn.Think about it.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 26, 2020, 04:48:31 am
content: Quote from: DougSpindler on October 26, 2020, 02:19:01 amMost likely sent to colder climates where heat pumps don't perform as well and where there's enough heating demand for CHP to make sense. Also, the infrastructure cost is more or less a fixed cost and that's what I was hinting at by the service charge.QuoteInteresting they extended net metering to allow conversion from electricity to gas.QuoteAre they really planning to shut down existing gas infrastructure anytime soon and render a lot of appliances useless? The only mention of anything relating to a phase out of natural gas only applies to *new* construction. From what I can see, existing buildings will just continue to work the way they have been working.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 26, 2020, 07:27:42 am
content: It is well possible that they will shut down some local gas infrastructure if there are major repairs needed. With decreasing supply the added investment in a major repair / renewal may not be worth it. This would render some appliances useless or require bottled gas instead.The price would not go down - maybe the money the producers get, but added taxes would make up for more than that, so much the demand will go down. It still needs extra effort to get the gas supply running and drill new wells. Many wells are only good for some 10 years or so and often is gradual decline from day 1. There would be still some demand from older houses, but it makes absolutely no sense to add new ones if the price is expected to sky rocket (maybe 10 times) so that many will convert.With better regulation and higher efficiency using electricity is no that much more expensive. Even if 10 times the price per kWh one would need some thing like 1/3 the energy and thus only 3 times the price. The ration depends on location - the factor of 10 is more like a high values. The main argument for cooking with gas is the higher power and the weak electricity grid in the US. With 230 V induction heating can also be fast.There is the option to use excess electricity to produce some gas, but this is still low volume and not very efficient.

author: f4eru
author_rank: Super Contributor
timestamp: October 26, 2020, 08:03:16 am
content: Quote from: DougSpindler on October 26, 2020, 02:19:01 amWe will keep it in the ground, where it belongs.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 26, 2020, 08:22:42 am
content: Quote from: f4eru on October 26, 2020, 08:03:16 amCan’t do that, the chemistry will not allow it as it’s package deal. We will continue to use hydrocarbons for fuel for decades to come. There is no way to select which hydrocarbons we want to take out of the ground and what to leave.

author: nctnico
author_rank: Super Contributor
timestamp: October 26, 2020, 11:38:10 am
content: Quote from: DougSpindler on October 26, 2020, 02:19:01 amTurn it into hydrogen. Likely this will happen with coal and oil as well. There is way too much potential to make money from fossil fuels to leave it unused in the ground. All the big oil companies are pushing hydrogen hard and they are going to succeed because they have tons of money to throw at it. Just pick a random oil company and you'll see they are investing in hydrogen.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 26, 2020, 01:17:52 pm
content: Quote from: DougSpindler on October 26, 2020, 08:22:42 amTransportation and machines will use hydrocarbons for lubrication, but much less is needed if they don't also burn fuel.We will have to cut down on the oil production quite a bit - this is even without caring about climate chance, the oil resources are very finite and not much more is found and if most of this is expensive to get out (e.g. deep see). There would still be enough use for natural gas (and similar) that comes out anyway, e.g. from old wells near there end of life or as a by product. For gas it is more like they start to limit new long term use or cut down on new pipelines. The resources to really cut down is coal and oil. It may not be long until the first countries call a stop on new gasoline driven cars.There is not much sense to convert natural gas into hydrogen - storage and many uses are better with natural gas. It is more like that in the more distant future on could convert hydrogen into methane for better storage.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2020, 01:24:44 pm
content: Quote from: Kleinstein on October 26, 2020, 01:17:52 pmIt doesn't make sense, but sense doesn't have much of a part to play in these decisions. Methane is certainly easier to handle than hydrogen, but if you are going to synthesis a convenient fuel, why not make it a liquid?

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 26, 2020, 01:51:08 pm
content: Quote from: nctnico on October 26, 2020, 11:38:10 amHow would you turn coal into hydrogen at anything approaching a good efficiency when there's practically no hydrogen in coal to begin with?The main barrier to widespread use of hydrogen at this point seems to be the high cost of fuel cells.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 26, 2020, 01:55:34 pm
content: What would be the chemistry and energy requirements to do all of this conversion?I would think the energy required for these chemical reactions would make it cost prohibitive.But then again if we have nuclear fusion power generation I guess we would have the energy to do these reactions.What we really need is a Manhattan like Project to get nuclear fusion figured out.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2020, 02:02:23 pm
content: Quote from: NiHaoMike on October 26, 2020, 01:51:08 pmThat's how most hydrogen is produced right now, and its not efficient. The hydrogen actually comes from steam, rather than the coal that provides the energy.You don't need fuel cells to use hydrogen for transportation. The hydrogen tanks, pressure valves and other components being used now by fuel cell cars were actually developed for experimental hydrogen powered ICE cars. I saw a hydrogen powered V12 BMW 7 quite a few years ago, at a show.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 26, 2020, 02:20:55 pm
content: Quote from: coppice on October 26, 2020, 02:02:23 pmProblem with Hydrogen powered ICE cars is the pollution they create in the form of NOX. From what I understand it's not much better than gasoline ICE.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 26, 2020, 02:49:07 pm
content: Quote from: DougSpindler on October 26, 2020, 08:22:42 amYou can if you want gas. You do it by choosing the location. It's done in the NE US, and other places as well. Of course, there are other hydrocarbon, but you get primarily methane and unusable salty, radioactive water in large quantities. The gas gets shipped away along with most of the money, and the waste gets dumped on the locals.John

author: Kleinstein
author_rank: Super Contributor
timestamp: October 26, 2020, 03:11:41 pm
content: Quote from: DougSpindler on October 26, 2020, 01:55:34 pmThe classical way to make hydrogen gas from coal is to add steam to red hot coal. This will produce a mixture with hydrogen, CO2, CO and methane. From pressure, temperature and additions one can change the mix a little, but in the end it needs cleaning of some kind. Electricity to methane start with hydrogen and AFAIK than adds CO2.The direct chemical way is still more efficient and cheaper than coal to electricity and than the hydrogen.Nuclear fusion is no that simple and chances are it would no be cheap energy. Most current concepts also have an intrinsic limitation, were there may be no easy technical solution. The fusion reactions need tritium and this tritium has to be made from lithium. The reaction is well understood and one problem is that the rate of tritium production will not be much higher than the quantity needed. The exact number depends on the details, but even best case there will not be much excess and it may already be difficult to get a break even. So the amount of available tritium will only increase slow - something like doubling every 20-50 years if all goes well, but hardly much shorter. Especially in the initial phase expect the growth to be slower due to extra down times.The number of possible fission reactors can not grow faster than the available tritium. The current world tritium reserves are good for maybe reactors of the currently envisions design. In 20 years it would be only 1 (and a little smaller) to start with as tritium naturally decays. So unless they get an additional magic source of tritium large scale fusion would be not before 2100 could be 2200. So even if they would have a ready fusion reactor, it would be to late and we would still need some other energy source for the next 100 years at least. This would be more than a short intermediate solution - more like several generations. So if at all fusion is something for a distant future, not a solution for the climate problem.It is more like distracting from more short term problems.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 26, 2020, 03:51:51 pm
content: @KleinsteinThank you. Nice explanation. But isn't this creating CO2? Something we don't want to create? And in doing so isn't it an exothermic reaction? Doesn't that mean there would be a lot of wasted heat?

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2020, 04:07:51 pm
content: Quote from: DougSpindler on October 26, 2020, 02:20:55 pmFuel cells also produce NOX. I'm not sure how the amount compares to an ICE engine, but they are not clean.What matters in the real world is all about fashion. The UK went massively for diesel, to cut CO2 emissions. As recently as 2017 some makers, like Volvo, were releasing new models as diesel only cars. A year later the country turned against diesels, partly because if the VW scandal. They put financial disincentives in place, and cities started trying to ban diesel cars from their centres. This wasn't just applied to old cars, but to all diesels, whether they were cheating on emissions or not. It all just fashion.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 26, 2020, 05:34:40 pm
content: Making H2 from coal of cause produces CO2. One can not really avoid this when using the energy from the coal.The normal fuel cells that run relatively cool (e.g. close to 100 C) do not produce NOX, at least not in relevant quantity. It can be more like a problem if the air is too dirty, as some pollutants can accumulate and limit the life time.Compared to a combustion engine the hydrogen fuel cell is also better efficiency - still not 100%: it consumes gases and produces liquid (water) and this naturally produces some heat. From the physical starting point the energy is hydrogen gas + oxygen gas is no all free energy ( in the Gibbs sense, not energy for free bull-shit). So 100% conversion to electricity is not possibly. The other side of this is that electrolysis can also be partially powered from heat and works better when hot.

author: nctnico
author_rank: Super Contributor
timestamp: October 26, 2020, 05:42:08 pm
content: Quote from: coppice on October 26, 2020, 04:07:51 pmNo. It is not a fashion. NOx and SO2 are harmfull gasses which kill people every day. So reducing these is very important for health reasons. The diesel ban was a long time coming because you can't really make a diesel engine run without emitting NOx. They started talking about this in Germany over 10 years ago. In a few years it is possible the same will happen to EVs in countries for which a significant part of the electricity is generated using coal or gas (either in the country itself or neighbouring countries). The resulting NOx and SO2 emissions from EVs are worse compared to a hybrid ICE and hydrogen fuel cells.This is starting to resonate in Germany already. This is a list with the cleanest cars as tested by the German ADAC:https://www.adac.de/rund-ums-fahrzeug/tests/ecotest/ecotest-ranking-sauberste-autos/. Note that none of the electric cars scores high in the column 'punkte schadstoffe' (points for harmfull emissions) due to emissions from electricity production.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2020, 06:02:10 pm
content: Quote from: nctnico on October 26, 2020, 05:42:08 pmOf course its a fashion. Some activists made a noise about CO2, and they clamped down on CO2. Some activists made a noise about NOX and they clamped down on NOX, relaxing on CO2. Many things are harmful, but which gets addressed is a matter of the activists de jour.

author: nctnico
author_rank: Super Contributor
timestamp: October 26, 2020, 07:58:38 pm
content: I call that new insights.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2020, 08:14:43 pm
content: Quote from: nctnico on October 26, 2020, 07:58:38 pmWhat new insights? The CO2 problem has been understood for a century, and the NOX and SOX problems for less time. However, in the 1980s we'd see something about the NOX and SOX problems on TV most weeks. Sometimes it was their relation to acid rain. Sometime it was their relation to respiratory issues in cities. ICE, and especially diesel engines, were already marked out as especially bad culprits in the case of city air. Some European countries already had a high percentage if diesel cars at that time, but places like the UK had almost none. The UK actively grew its fleet of diesels cars in a time of full awareness of their effects. That's why their adoption was accompanied by the EuroX specifications for emissions. Now it doesn't matter if your engine is complaint or cheating, if you make diesels you are this week's bad guys. Its just fashion.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 26, 2020, 11:21:06 pm
content: Quote from: nctnico on October 26, 2020, 05:42:08 pmWhat about the emissions from refining crude oil into gasoline or diesel? I doubt that part is emissions free.If generating electricity makes too much emissions, address that problem directly, such as by restricting the most polluting generators to be used for emergency power only.

author: nctnico
author_rank: Super Contributor
timestamp: October 27, 2020, 12:12:20 am
content: Quote from: NiHaoMike on October 26, 2020, 11:21:06 pmThose are really low. See this document for the numbers:https://www.eea.europa.eu/publications/emep-eea-guidebook-2019/part-b-sectoral-guidance-chapters/1-energy/1-b-fugitives/1-b-2-a-ivFor NOx: 240 grams per metric ton (1000kg). Let's assume 100% of the crude oil input is converted to gasoline. A metric ton is about 1100 liters of gasoline which drives a hybrid 22000km in an actual usage scenario. 240gr/22000=10 milli grams per km. Again, this is assuming 100% of the crude oil is turned into gasoline which it isn't so the actual number is much lower. For reference: the euro6 limit is 60 mili-grams per km. A Toyota Prius sits at 4mg NOx per km (https://www.which.co.uk/reviews/new-and-used-cars/article/car-emissions/low-emission-cars-aS2iB6E0PQeK).According to the Dutch statistics bureauhttps://opendata.cbs.nl/statline/#/CBS/nl/dataset/83390NED/table?ts=160375625740245460 metric tonnes of NOx where emitted for energy production in 2019. With a total of 121TWh produced that comes down to 375mg of NOx per kWh. Hence an EV which sits somewhere between 200Wh to 250Wh per km in actual usage scenarios results in an NOx emission of 75mg to 94mg per km. That is way over the Euro6 limit!QuoteThe latter costs too much. In the end there is only so much you can filter without making the costs insanely high.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 27, 2020, 01:58:24 am
content: Quote from: nctnico on October 27, 2020, 12:12:20 amSo for the high estimate, adding enough wind or solar power to cover 37% of the EV's usage will bring it to just within the limit.QuoteIf you want to slow the adoption of EVs because of the emissions problems (that unlike gasoline and diesel cars, can be improved over the life of the vehicle), making them less competitive with hybrids will do it, and solve the original problem.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 27, 2020, 03:08:31 am
content: Quote from: NiHaoMike on October 27, 2020, 01:58:24 amThat’s not going to happen. We don’t have enough raw materials to build enough wind turbines and solar panels for anywhere near 37%. We could do a lot of things if only we had enough raw materials. The raw materials awe limiting what we can do.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 27, 2020, 03:41:13 am
content: Quote from: DougSpindler on October 27, 2020, 03:08:31 amSolar panels are made mostly from silicon and there's no shortage of sand to get it from.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 27, 2020, 07:58:01 am
content: The materials for solar cells are a weak point: there is plenty of silicon, but solar arrays also need quite some copper for the interconnections. Another point is that it needs energy to produce the steel, aluminum and glass. The glass for the solar panels is usually made with energy from natural gas - so higher energy prices there would also raise the costs for the solar panels. It is still only several months worth of energy production, so not a real limit to the speed of expansion.Other power plants also need quite some effort to build - the numbers are not that different.For the NOx emissions there is a difference between those directly from the cars and those from large power plants. NOx is especially troublesome in the cities and it is a relatively short lived pollutant. At a moderate level plants actually like it as a fertilizer. It only gets a problem in higher concentration to lower the PH of the soil too much. With much reduced sulfur emissions this is no longer such a problem as in the 1980s.Hydrogen, like electricity is only a way to transport energy, it is not a source available in nature. Even fuel cells are lower in efficiency than lithium batteries. Just storage is easier with hydrogen. In a car / truck the fuel cells are more like a way to extend the capacity and speed up refueling. Remove the fuel cells and you have an EV with a rather small battery. The shift of the cars from ICE to EV (or hydrogen fuel cells) only makes sense of much of the electricity is no longer from fossil fuel. With electricity from coal an EV is dirty.

author: nctnico
author_rank: Super Contributor
timestamp: October 27, 2020, 08:48:56 am
content: Quote from: NiHaoMike on October 27, 2020, 01:58:24 amJust within the limit indeed. I used the euro6 limit but there are newer (stricter / lower) euro6a-b-c-d limits. However I have not been able to find numbers for the limits. And then there is SO2 output as well from electricity generation. The bottom line is that for an EV to be cleaner compared to a clean hybrid the percentage of fossil fuels used for generating electricity needs to be in the single digits. That isn't going to happen this decade (except for the few areas which are powered from hydro and nuclear for well over 90%). The best thing to do is to use electricity only for things which can't be powered otherwise. By reducing electricity usage the percentage of renewable electricity automatically increases.@Kleinstein: NOx is also a long term problem as well because it accumulates in the soil and disturbs the balance between plants. In the Netherlands this is a major issue; in some areas the soil needs to be replaced (like after a toxic spill) due to the high amounts of nitrogen in it.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 27, 2020, 09:18:11 am
content: @coppice Can you explain how Fuel cells produce NOX? I'm not sure how the amount compares to an ICE engine, but they are not clean. Where is the N coming from?

author: coppice
author_rank: Super Contributor
timestamp: October 27, 2020, 12:07:12 pm
content: Quote from: DougSpindler on October 27, 2020, 09:18:11 amThe NOX comes from the same place as NOX comes from with an ICE engine. The fuel cell uses hydrogen and air. The air contains oxygen and nitrogen, and some of it reacts. Everything I've read about fuel cells points out that some NOX is produced by their operation, but is vague about how much. e.g. The wikipedia page on fuel cells says "In addition to electricity, fuel cells produce water, heat and, depending on the fuel source, very small amounts of nitrogen dioxide and other emissions.". What is a very small amount? A 1960s car produced very small amounts of nitrogen dioxide, but that was enough to cause a lot of trouble, and has been substantially reduced today.

author: nctnico
author_rank: Super Contributor
timestamp: October 27, 2020, 01:34:47 pm
content: Quote from: coppice on October 27, 2020, 12:07:12 pmGoogle it. I did find a graph which shows minimal (several order of magnitudes less compared to ICE) NOx emissions from hydrogen fuel cells. The key is to keep the temperature low enough so the nitrogen doesn't bind to the oxygen.

author: coppice
author_rank: Super Contributor
timestamp: October 27, 2020, 03:15:11 pm
content: Quote from: nctnico on October 27, 2020, 01:34:47 pmBRILLIANT! Whoever would have thought of Googling something? You Sir, are a bloody genius. Now, if you Googled it and found a actual page with hard data, you might post a link. Obviously, temperature is a factor. Its the main reason hot diesels are worse for NOX than cooler gasoline engines. However, there are other factors, like catalytic behaviour.

author: JohnG
author_rank: Frequent Contributor
timestamp: October 28, 2020, 07:38:39 pm
content: For those who have an interest in NOx, here is a pretty good introduction for a technically oriented non-expert that a former coworker recommended to me. He was a engineer working on diesel-electric locomotives, where NOx control is serious business.https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdfTL;DR: NOx production depends on high temps and available reactants. Typical fuel cells run at much lower temps than ICEs, so the NOx production rate is much lower. Note that many (most?) chemical reactions have an exponential dependence on temperature.John

author: Electrodynamic
author_rank: Regular Contributor
timestamp: October 29, 2020, 04:45:46 am
content: In the long term wind and solar should outperform fossil fuels because they are renewable, sustainable and recyclable. So as fossil fuels become more scarce and expensive renewables are becoming cheaper and more efficient. It's just a matter of time.I suspect the oil and gas industry is in big trouble because they cannot even afford to properly abandon there wells or replace untold miles of pipe rotting in the ground. The newest craze in the patch isn't drilling but patching all those old pipes leaking like a sieve. So generally speaking fossil fuels do work however it's becoming more problematic and all the damage they do is off loaded to the tax payers. There is no free lunch.Regards

author: f4eru
author_rank: Super Contributor
timestamp: October 29, 2020, 10:23:54 pm
content: Quote from: DougSpindler on October 27, 2020, 03:08:31 amNope. Germany is at 53% now. Any country can. No shortage of materials involved.

author: Electrodynamic
author_rank: Regular Contributor
timestamp: October 29, 2020, 11:09:29 pm
content: The facts look pretty straight forward and if there was no profit in wind and solar it wouldn't be growing like a wildfire even without subsidies.For example, a couple years ago a friend wanted me to explain everything about grid tied solar to his boss who owns a fracking company. Last I heard he bought 120 acres of land and is almost finished construction on his 20MW solar farm. If the old school oil patch boys are jumping in with both feet you can be sure there's a great deal of money to be made and it's the future.Regards

author: Cerebus
author_rank: Super Contributor
timestamp: October 30, 2020, 12:16:51 am
content: Quote from: f4eru on October 29, 2020, 10:23:54 pmCheeringly, the UK clocked up a coincidental 53% of all generation from renewables yesterday, 43% of all generation from wind, nearly bugger all from solar (a few 100 MW, rained much of the day, itisEngland in late October.13% on a good day), biomass and hydro made up the rest.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 30, 2020, 08:36:16 am
content: The first 50% or so of renewable power is the easy part as it does not need much storage. The remaining fossil power plants can substitute storage. For those simple part wind and solar have a clear cost advantage. In areas where much power is needed for cooling solar power can be used for even more without much need for storage. Despite of very low support in the US, wind power is growing quite a bit in some areas. Solar is also strong in the southwest, despite of the rotten grid and power companies. Hard to tell if the subsidies paid are for the solar or the grid in general - on hot days the spot market price is high. So it is hard to tell the true value of the electricity from PV.The tricky part comes with close to 100% renewable power, as it would need quite some storage. Depending on the conditions the storage may be more expensive than the generation itself. It may still be our best bet and still be cheaper than new nuclear.The hard part here is the long term storage from summer to winter in countries that need significant energy for heating. Wind power at least often is also working well in winter. However not all countries have good conditions for wind. Conditions look good in the UK (windy and winters not too cold), but it can be tricky in countries like Poland with colder winter and lower wind speed. Solar energy in winter is going down quite a bit. Wind energy may need storage for a few weeks, but not so much for a 1 year cycle.

author: DougSpindler
author_rank: Super Contributor
timestamp: October 30, 2020, 09:35:52 am
content: Quote from: Kleinstein on October 30, 2020, 08:36:16 amHasn't this been the issue all along? Energy storage systems such as liquid metal batteries could be the answer. We are 95% there, but just can't seem to figure out that last 5%.It's not easy.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 30, 2020, 09:57:35 am
content: There are batteries (Li, sulfur-sodium and similar) for short time storage, but they are still quite expensive. The numbers installed are still relatively low, so the price may still come down, but not sure how much and not yet.The batteries are mainly for the day / night cycle, especially with PV. Here they may become cheap enough and with some 200 cycles a year it fits the usual life time. They can also help with fluctuation in the wind, but this is more with wether cycles that are more like 1-2 weeks. This is already more on the long side for batteries.For longer term, like summer to winter the batteries are just too expensive, as they would get only very few cycles.My best guess here would be hydrogen: it still needs the cost to come down, but there is a chance this can happen. Some of the storage can be hydro, but here the capacities are limited.Those countries / regions that have already a high percentage from wind / PV (e.g. Danmark, Germany, Carlifornia, Australia in parts ? ) now have to start with build up of storage. Chances are it would be similar to wind and PV with initially high costs, so that the first 10% would be relatively expensive. There is a start, but a slow start.

author: ahbushnell
author_rank: Frequent Contributor
timestamp: October 30, 2020, 10:59:41 am
content: Quote from: Kleinstein on October 30, 2020, 08:36:16 amThe peak demand in CA happens as the sun is getting low.This shows power demand in CA. Notice the peak is late in the day.http://www.caiso.com/TodaysOutlook/Pages/default.aspxI was watching this while the blackouts were going on and I noticed the available wind was going low during the day. Green energy is a problem in CA now. They are starting to build up energy storage which is the big requirement. 50% green needs storage. Do you think the system will stay up if half the power is not available.http://www.caiso.com/TodaysOutlook/Pages/supply.html

author: coppice
author_rank: Super Contributor
timestamp: October 30, 2020, 11:03:53 am
content: Quote from: DougSpindler on October 30, 2020, 09:35:52 amYou have this backwards. We have only addressed the low hanging fruit so far. We are maybe 5% of the way there. The hard work has hardly begun.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 30, 2020, 12:56:05 pm
content: Quote from: ahbushnell on October 30, 2020, 10:59:41 amThe temperatures lag the sum by a few hours, thus highest temperature in the afternoon. Here some intelligent control may help to already cool down the house when the electricity is available. Chances are this will start if it gets cheaper to use your self produced PV electricity directly than going through the grid.If the change to 50% renewable comes from adding PV + wind without increasing demand the the old power stations can be still there for the times when there is no wind or sun. The old stations just get less hours. Carlifornia however had a weak grid for a long time and increasing total consumption, so the old stations are insufficient as a full backup. So they now need storage - maybe a little before getting 50% renewable. I doubt it would make sense to build new conventional power that would only see little active time.With about 50% (on average) from wind and PV there are now times in Germany when there is excess energy from wind and PV. There is some storage capacity ( hydro), but net jet very much. The conventional power stations as a backup take the function of storage. We essential need storage for the conventional stations going of the grid, not so much the wind or PV added. The added wind and PV reduce the active hours for the conventional power stations and thus indirectly are reason to take them off grid.

author: Electrodynamic
author_rank: Regular Contributor
timestamp: November 02, 2020, 09:14:24 pm
content: KleinsteinI think Germany is much further ahead than most other countries. I also thought the idea of community owned CHP, wind and solar was a brilliant way to not only lower the costs but prevent monopolies from taking over and raising the prices later. Big may have been better 30 years ago however with technology changing so fast the all in strategy is stranding assets and there becoming almost worthless within a short time period.All it would take is a jump in solar efficiency of maybe 15-20% and within 5-10 years most companies would become insolvent. With low margins they can't afford to upgrade nor can they afford to operate in a competitive market. Meanwhile the politicians keep subsidizing outdated fossil fuel technology holding everyone back. If they ever levelled the playing field and included all long term external damage like environmental pollution most fossil fuel technologies would have been bankrupt a long time ago.Regards

author: Kleinstein
author_rank: Super Contributor
timestamp: November 03, 2020, 12:07:23 pm
content: Germany is relative far in converting to renewable electricity, but the hard part is still to come, the first 50% are the easy part as it can be done with little extra buffers. I would definitely not expect a large increase of PV efficiency. It is already not that far from the theoretical limit (Shockly-Quisar limit). The good cells may get cheaper though - so cells that were at a premium price may become more affordable.With storage and a strengthened grid it again needs a central control and thus more like large companies The pure production part can be small units like individual home owners and farmers for PV, or smaller companies for wind turbines. We are at the point that also the large electricity companies start investing in wind and PV. Fossil fueled power stations get increasingly difficult as they get less and less active time, so even with no added tax on the fuel they get increasingly less competitive. The critical point is more that storage is still too expensive. The critical point would be when wind plus storage gets cheaper than coal. Wind alone already already is for the times when the wind blows and with reasonable conditions.

author: nctnico
author_rank: Super Contributor
timestamp: November 03, 2020, 08:10:13 pm
content: Quote from: Kleinstein on November 03, 2020, 12:07:23 pmAnd there is another problem to address as well. Once the big power plants are in the minority all those smaller generating units like wind and solar have no solid mains grid to synchronise to. This means that all those generating units will need an accurate time source to stay synchronised. And no, GPS is not going to be it because it is way too susceptible to sabotage. The US and UK are already taking steps to offer a reliable alternative to GPS for time but needless to say this will require infrastructure and thus adds costs as well.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 03, 2020, 10:39:08 pm
content: Quote from: nctnico on November 03, 2020, 08:10:13 pmInject a modulated tone on the mains to act as a time reference.

author: Cerebus
author_rank: Super Contributor
timestamp: November 03, 2020, 11:06:13 pm
content: The synchronisation thing is an all but a solved problem. Mobile phone and SDH systems rely on very precise synchronisation, there's a clock distribution network across several tiers (each referred to as a stratum) already in place. It's needed for clean hand-off between cells, among other things. It would be reasonably simple to piggyback on this for grid synchronisation. G.811 specifies that the primary clock for this should have a stability of \$10^{-11}\$ — good enough to keep 50 Hz or 60 Hz in check across the whole power estate I think.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 12:31:36 am
content: Quote from: Cerebus on November 03, 2020, 11:06:13 pmVarious things give us atomic clock accurate timing signals. Broadcast TV line scan rates. for example, come from a similar precision clock. The SDH isn't much use for these things any more. The network no longer presents mere mortals with a direct output from the SDH, like we used to get with ISDN. I don't see what problem this solves, though. You can't blindly generate according to a precision clock. You have to go with the flow. No one small generator can make the world fall into line with it.

author: ahbushnell
author_rank: Frequent Contributor
timestamp: November 04, 2020, 12:55:31 am
content: Quote from: nctnico on November 03, 2020, 08:10:13 pmMany of the wind and solar plants are not small. Control systems make the plant behave in a manner the same as a power plant. It a matter of making the sure the small and large systems meet the control standards. Note that batteries (or energy storage) are a critical part of this.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 04, 2020, 02:03:09 am
content: My interpretation is that although you can make the inverters just sync to the local grid, having an independent timing reference solves the problem of two parts of the grid drifting out of sync with each other if they become separated for some reason. Most likely how that would work is the inverters sync to the grid just like they currently do, but if the timing is way off compared to the reference, try to use a phase shift to pull it back in sync with the reference. If the majority of generation on that isolated segment does that, that will succeed in pulling it in phase with the rest of the grid and allow it to be reunited.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 10:58:06 am
content: Quote from: coppice on November 04, 2020, 12:31:36 amNot any more they don't. We haven't been transmitting analogue TV signals with an explict line scan for a few years now.Quote from: coppice on November 04, 2020, 12:31:36 amWe're talking about a different world here, where there aren't enough large mechanical generators to dictate the grid frequency in relation to load. The current behaviour, that grid frequency is load related is an undesirable property, and is a side effect of load dictating frequency because of whirling rotors slowing under load and speeding up with shedding of load. In a generation network where most of the generation sources are interfacing to the grid via inverters, the load -> frequency relationship has gone, there's no reason for it to be there. Thus, as someone said earlier, we have to come up with a method of making sure that everyone keeps in sync.As to getting to a telco's frequency and time standards, well access to them is already buried inside your mobile phone, you just aren't actively aware of it. If there was a demand, brought on by widespread local generations, I'm sure it wouldn't be long before one of the mobile chipset makers would produce one that had a pin with a network locked 50/60 Hz signal on it.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 05:30:10 pm
content: Quote from: Cerebus on November 04, 2020, 10:58:06 amI think you'll find the digital systems still use an atomic clock, even though some networks are broadcasting a mixture of frame rates. I think they need it so multiplexing the various feeds works OK at the transmitter. The muxing issue, at the studio rather than the transmitter, was the original reason the analogue systems went to atomic clock based timing.Quote from: Cerebus on November 04, 2020, 10:58:06 amEven if the majority of things feeding into the grid have access to a common master clock, they still can't blindly generate as they please. They need to follow the phase they see from the grid. Now, if you want a million power sources to try to gently push that phase forwards or backwards towards an ideal phase rate, I suspect you are going to have some funky stability issues. During periods when pools of generation can fully supply their locality they begin to island. In those circumstances they will collectively find it much easier to push the phase, and will start to misalign with other pools. I suspect some amount of networked control information will be needed.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 06:40:22 pm
content: Quote from: coppice on November 04, 2020, 05:30:10 pmYou saidline scans, which were indeed needed for synchronisation in the world of analogue television. There is no synchronisation between transmitter and receiver needed with MPEG or H.264. One can record, and indeed I do, the multiplex stream as bits on a disk and play it back later. Television programs are just data nowadays, there are no 'lines' per se thanks to DCT encoding.Quote from: coppice on November 04, 2020, 05:30:10 pmIt just needs synchronising, plain and simple. If it's synchronised, that's it, problem solved. The only question remaining is the source of the master synchronising signal. At the moment, with largely mechanical generation it's the grid. Once that is no longer the case (which is where we started) there needs to be an agreed source.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 04, 2020, 06:44:48 pm
content: When current systems were connected in larger and larger grids control problems definitely did develop. There have been several decades of control theory and implementation of appropriate feedback loops and the systems are now largely (but not completely) stable. I don't see anything that makes control of these distributed sources technically impossible, but it will require a substantial amount of work and probably take a similar amount of time to work out all of the nasty details. One key difficulty in achieving this will be in getting thousands or more independent suppliers to cooperate in the solution. Hopefully if enough join in the control mechanism the rest can be treated as noise and won't cause serious difficulties.

author: nctnico
author_rank: Super Contributor
timestamp: November 04, 2020, 06:52:14 pm
content: Quote from: Cerebus on November 04, 2020, 10:58:06 amNot just that but in today's world a lot of telecom infrastructure is frequency synchronised only. Not time (see below why that is important). That will change in the next couple of years due to 5G but that doesn't solve the issue that a lot of telecom infrastructure is ultimately relying on getting the time from GPS which leave the infrastructure open to time shift and jamming attacks.And then there is also the issue that all those micro 'generators' need to output the mains at the right phase angle. Micro-second accuracy requires knowing the location in respect to the cable layout down to a couple of hundred meters. Think about mobile sources. And before you say GPS... Suddenly DC distribution starts to look really good.

author: Kleinstein
author_rank: Super Contributor
timestamp: November 04, 2020, 08:17:24 pm
content: There is no need for the small generators to very accurate with the phase. If they are off a little, some of the current they deliver will be just reactive power, but most would be still OK. It would be at the distribution transformers to add up the reactive power and ideally keep the reactive power going through the transformer to be small.There is no really complicated control theory needed to make the electronic inverters behave like a large rotary machine, at least for the short term. They can even do more and actively counteract harmonic distortion of the grid-voltage. Like now, there is no need for the generators to be all independently synchronized they get the synchronization from the grid. It only needs a few to control the frequency, so the clocks would still run OK.The small inverters use for solar should already be quite good, as additional reactive power would usually not be paid and so they already have an incentive to not have too much of it. They somehow need some to make shure the grid is still there and the don't do islanding. Locally the grid already has to manage situations with near 100% from PV and wind. It does not happen often, but already happened that essentially no conventional power station in Germany was active.With more storage online, at least those based on batteries of hydrogen could in principle also stabilize to grid. These larger inverters can be bidirectional, so they can help in both directions.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 08:18:18 pm
content: Quote from: Cerebus on November 04, 2020, 06:40:22 pmPeople usually say line scan, because that's what was usually measured. I was sloppy. Its actually the frame scan rate that was important, because it caused serious problems if the frames from different sources slid relative to each other. Once you have recorded the digital bit stream you have broken the need for synchronisation. However, when broadcast the various bit streams going into the mux need to be locked in bit rate, just like the SDH for telecoms, or you get overflows or underflows in the buffers when one stream is faster than another.Quote from: Cerebus on November 04, 2020, 06:40:22 pmSynchronised systems don't magically stay synchronised. They need to perform constant tracking, and they need to track in a robust and stable manner.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 08:21:27 pm
content: Quote from: Kleinstein on November 04, 2020, 08:17:24 pmThat's true while the small generators don't dominate the network. They just fall in line with the big systems. However, where small generators grow to be a really large part of the mix they become the thing that needs to be the source of stability. If they are all wobbling around with their phase there could be some nasty results.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 08:33:44 pm
content: Quote from: coppice on November 04, 2020, 08:18:18 pmThe H.222 transport stream muxes are packetised, there's no synchronising of bitstreams needed.QuoteNow you're just stating the obvious.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 09:03:41 pm
content: Quote from: Cerebus on November 04, 2020, 08:33:44 pmThat is irrelevant. This is a general streaming comms system design issue. e.g its why we had the messy PDH and it gave way to the SDH. Take a comparable streaming system most of us use often, even when we don't realise it - VoIP. To work best, VoIP needs the ADC at one end, and the DAC at the other end to run from the same clock. In between is a messy packet switched system which doesn't convey a clock end to end, although if working well it does accurately convey the bit stream between the ADC and DAC. When one or more or the VoIP terminations is a consumer box the unmatched clocks mean there are overflows or underflows at the DAC, which the software has to fudge over so they don't sound too audible. If both VoIP terminations are in a telecoms provider they can get the ADC and DAC clock from the SDH or from a local rubidium clock, and the audio stays clean. This is why feeding a modem through a telco's VoIP channel usually works, and feeding it through a consumer VoIP adaptor doesn't. Modems can't ride over temporal hiccups. Its many years since I looked at the specs for broadcast TV, but it does allow you to extract an accurate clock from the received signal and use that to clock the local DACs. However, for that to work with several studios feeding into the same mux, they need to be using precisely the same clock rate - hence the use of atomic clocks. I don't know if everyone implements this properly. or if many people rely on the masking algorithms used to fudge over underflows and overflows, but the system can do things properly.

author: nctnico
author_rank: Super Contributor
timestamp: November 04, 2020, 09:44:09 pm
content: AFAIK broadcast is still using frequency synchronisation even in the era of compressed streams. However it doesn't seem difficult to me to morph 2 frames into 1 or 3 frames in order to sync. Maybe this is already happening to match the framerate of the display panel.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 10:44:51 pm
content: Quote from: coppice on November 04, 2020, 09:03:41 pmIt is completely relevant because thatishow it works.I start with a minor remark about re-utilizing Telco synchronization as a possible source for grid synchronization, you seem to then set out to derail that, and go down this succession of wrong turns trying to prove your point via analogue TV, DTV, and now VoIP. I really don't know why you do this. You've wandered a million miles off topic and in doing so demonstrated that you don't understand how DTV works or VoIP.Clocking local DACs for DTV? The thing isdigitalfrom the output socket on the camera (SDI), via transmission (MPEG, H.264, H.265, AAC etc all packetised into H.222 and pumped over DVB-T using OFDM modulation) all the way to the display in someone's living room with possibly a diversion via a (digital) HDMI cable.I used to run UK International licensed voice carrier services over a pukka Ericsson voice switch then via VoIP to the rest of the world and to our German gateway Nortel DMS. All that stuff about clocks and VoIP is pure unmitigated hogwash - it's exactly the kind of thing I'd expect to hear from someone confabulating to prove a mismade point but not from a knowledgable practitioner.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 10:57:16 pm
content: Quote from: Cerebus on November 04, 2020, 10:44:51 pmI guess you never bothered probing how that thing worked. I've built these things from the ground up.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 10:58:06 pm
content: Quote from: nctnico on November 04, 2020, 09:44:09 pmNo, it really doesn't work like that. There are timestamps in the digital stream, the time sequence of frames, and of the (separately packetised) sound synchronisation with the video, is controlled by those timestamps. The whole lot is multiplexed, packet by packet, into anMPEG Transport Streamalong with other channels and transmitted. Frame rate for the panel is determined by fields in the encoded video data that will say "this is 24 fps video" in encoded form, the frame rate signal is free running. Any slip is easily accomodated in real time broadcasts by just dropping or repeating a frame if the slip is bad enough to exceed the buffering capability of your decoder.

author: Cerebus
author_rank: Super Contributor
timestamp: November 04, 2020, 11:18:55 pm
content: Quote from: coppice on November 04, 2020, 10:57:16 pmWell, the problem here is that I do know how "that thing" worked.So, do you really want to go down this route again? Last time it was mainframe companies, and you claimed "Burroughs was on its knees in 1980, and died in 1986." to prove me wrong, when of course Burroughs is still going today after changing their name to Unisys after taking over Sperry-Univac that year. You have previous form here. Let's say I'm sceptical about your claimed experience.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2020, 11:25:34 pm
content: Quote from: Cerebus on November 04, 2020, 10:58:06 pmYou can drop video frames, and people hardly notice. Its the audio that needs to be precise. If you drop a sample you get a nasty pop. If you drop a whole frame of the compressed audio then music stutters. You at least need to apply a fudging algorithm to fill in gaps or smooth overlaps. Anyone who has dealt with streaming audio that doesn't have the benefit of a precision clock should be very familiar with this.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 05, 2020, 12:32:08 am
content: Coppice, I think that what you described is how digital transmission for satellite and cable is basically how it works here in the US. But the implementation isn't good enough for grid sync.Yes, the audio comes through with no glitches and the video frames either work or aren't noticed when they are dropped or added. But depending on the decode path the audio and video aren't synchronized with each other (lip movement doesn't match sound), and neither is tied closely to real time. I can have the same station playing in two rooms of my house through the satellite TV connection and the two will have a time offset of many seconds. I don't know where these errors are inserted, haven't ever dived into the implementation.I'm not saying the problem is all that hard to fix, just that it does require some polishing on the existing system.

author: Kleinstein
author_rank: Super Contributor
timestamp: November 05, 2020, 08:05:59 pm
content: Some TV sets have an adjustment for a time delay between the picture and audio, especially digital audio out.

author: nctnico
author_rank: Super Contributor
timestamp: November 05, 2020, 08:35:16 pm
content: Quote from: CatalinaWOW on November 05, 2020, 12:32:08 amI doubt that. TV is on the decline anyway and in many places it is distributed over internet already so there is no time sync to derive from it. However a fixed internet line (copper or glass fiber) would allow to transport PtP time synchronisation but that protocol is not secured at all.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 05, 2020, 11:51:19 pm
content: Fixed internet is only going to exist in relatively densely populated areas, so can't be the whole solution to sync. But it might be the cheap answer where it works. Us rural types will just live with hand me downs as usual.

author: coppice
author_rank: Super Contributor
timestamp: November 06, 2020, 12:17:00 am
content: Quote from: nctnico on November 05, 2020, 08:35:16 pmThey like to keep old TV broadcasts alive for a very long time, but are happy to kill old cellular systems fairly quickly. It will be interesting to see if current TV broadcasts outlast 5G.

author: nctnico
author_rank: Super Contributor
timestamp: November 06, 2020, 12:25:28 am
content: Over here TV broadcast has been dismantled a few years ago. And nobody said cellular systems are a good replacement -they aren't-.

author: coppice
author_rank: Super Contributor
timestamp: November 06, 2020, 12:27:09 am
content: Quote from: nctnico on November 06, 2020, 12:25:28 amDo you mean all TV broadcast has stopped, or just the analogue systems?

author: nctnico
author_rank: Super Contributor
timestamp: November 06, 2020, 12:30:23 am
content: Quote from: coppice on November 06, 2020, 12:27:09 amJust the analog and older digital systems; nowadays it is all streamed over internet using copper or glass fiber over here.

author: Gyro
author_rank: Super Contributor
timestamp: November 08, 2020, 10:45:31 am
content: Quote from: coppice on November 04, 2020, 11:25:34 pmUnfortunately such systems have fallen foul of consumer product cost reduction! Back in the '90s when I was designing 1st generation Digital Set Top Boxes, the used 27MHz canned VCXOs which were accurately synced to the broadcast transport stream to maintain the buffer at half full. There was no problem with accurately presenting the audio and video packets at the correct timestamp.Skip and repeat was a 'fallback' which was only used to prevent buffer under/ overrun when initially syncing to a new transport, or for particularly dodgy broadcasters - there were/are three levels of specified transport stream accuracy, 1st for national broadcasters, 2nd for independent broadcasters and 3rd for porn channels (I forget the technical term), dependent on the accuracy of their reference.Then BOM cost reduction started biting, chipsets went from separate Tuner, Demodulator, Transport Demux, A/V decode, and external video + audio DACs (where you had some design choice in quality differentiation of implementation) to single chip (+ front end integrated NIM) with integrated A/V voltage output DACs. The canned VCXO became a simple 27MHz crystal with a VCXO IC to trim it. Still reasonable synchronisation though.By 2000, the single chip solutions no longer had a buffer level controlled VCXO control output and the frequency reference was just a bog standard cheap 27MHz crystal. By that point skip and repeat became the default (only) way of keeping vaguely in sync. It no longer even depends on the quality of the broadcaster's reference - it depends on the accuracy of the crystal in the individual device!As with most things, quality has switched to sh*t and nobody cares! I'm glad I'm not in that sector anymore - nobody is prepared to pay for quality in consumer gear!.