Elon Musk just offered to fix South Australia's energy problems - Page 1
Forum section: electronics / general

author: Tinkerer
author_rank: Frequent Contributor
timestamp: March 11, 2017, 12:12:59 am
content: http://www.cnbc.com/2017/03/10/elon-musk-fix-south-australia-blackouts-energy-problems-for-free.htmlThats fix them in only 100 days or he does it for free. Think he can do it? Basically 3 months to solve what is likely a large scale issue.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 12:14:28 am
content: AFAIK he made no such claim it would fix any systemic network issues, he's just offering to install a system in 100 days or it's free.I just offered to go there and film the installation.

author: Bud
author_rank: Super Contributor
timestamp: March 11, 2017, 12:19:15 am
content: For f#k sake do not allow him, or he will say he did not go to Mars because he was going to the Moon but did not because he was busy fixing OZ energy problem.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 12:21:50 am
content: Quote from: Bud on March 11, 2017, 12:19:15 amI suspect a couple of tweets doesn't take up much of his time. It's not not he'll personally negotiate the contract and oversee delivery

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 12:28:24 am
content: It is up there with the batteriser and Fontus. He "promised" to install somewhere between 100 MWH and 300 MWH of batteries. Absolutely no mention of how they are going to be connected to the grid and the way the inverters would operate.South Australia's mean power consumption is in the order of 2 GW. Is he going to install 2 GWs of inverter systems which could then run the state for maybe ten minutes. Would the inverters be able to operate in a stand alone off-grid mode if the feeder from Victoria was down and the wind stopped blowing? This is one large marketing exercise which unfortunately has much of the media kissing his arse. It's a complete scam.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 11, 2017, 12:43:29 am
content: Elon is a show-off!I assume this 100-300MWH syorage is going to be in one place,if he is to have any hope of doing it in the quoted timeframe.If so, it is just as vulnerable to the loss of distribution systems due to severe weather events as anything else.In any case, assibeenpointed out, the quoted capacity is "a drop in the ocean" compared to SA's usage.Australia has the unusual problem of being averylarge country with a quite small population, so easy fixes which might "sort of" work elsewhere fall flat on their face here.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 12:57:17 am
content: Quote from: sibeen on March 11, 2017, 12:28:24 amNo it's not a scam, it's a 100+MWH battery storage solution, nothing more. How that would be implemented in a practical scenario on a state based grid system and what performance gains it can get or issues it can and can't fix is a very complex issue that is very likely not Tesla's place to solve, it's the state energy architects role.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 01:01:03 am
content: Quote from: vk6zgo on March 11, 2017, 12:43:29 amHe also gets shit done. Not usually on time, but he usually delivers.This was master level marketing and the media lapped it up.Is it Tesla going around saying they know what the problems are specifically and can fix SA's problems?, or is it the media?

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 01:15:23 am
content: Quote from: EEVblog on March 11, 2017, 12:57:17 amIf it's just a 100+MWH battery it is not a solution. Not even close.A marketing scam.

author: ludzinc
author_rank: Unknown
timestamp: March 11, 2017, 01:17:29 am
content: Cost analysis benefit please.And keep it in mind that 100MW is small compared to standard base load power.Can pumped hydro deliver the same benefit for less overall cost (no need to swap out the water in 10 years, like the lithium batteries).This will give the grid only a buffer to ride through transitions. Not to cover increasing demand.And it won't help if the interconnector cannot supply our needs above our internal generation capacity.Going to be real interesting next summer with Hazelwood gone, and if it's not as mild as our last one has been....

author: rrinker
author_rank: Super Contributor
timestamp: March 11, 2017, 01:41:52 am
content: I think the idea is the battery bank would be for short term surges. Or at least provide some demand leveling. If he says between 100 and 300MW and the average load is 2GW and he hits right in the middle at 200MW, that's a 10% buffer. Maybe enough, maybe not - it can't hurt though.Just get the flux capacitor from the auto parts store and you have 1.21GW which should be PLENTY.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 11, 2017, 01:42:05 am
content: People come up with doubtful solutions all the time.Some hero over on Whirlpool suggested a HVDC line from West Oz.-EEEK!Not even to SA, though, he was talking about to NSW-------thousands more km of towers to blow over!We do have a lot of Natural Gas, but I don't think that even in their wildest dreams are the Eastern States ready to stump up for extra generating capacity in WA.

author: Brumby
author_rank: Unknown
timestamp: March 11, 2017, 02:08:44 am
content: Quote from: vk6zgo on March 11, 2017, 01:42:05 amNot many people realise how big Australia is.For those who aren't aware - it's comparable in size to the continental USA...And for Europe:

author: Someone
author_rank: Super Contributor
timestamp: March 11, 2017, 03:48:42 am
content: Quote from: sibeen on March 11, 2017, 12:28:24 amIts not a scam at all, when they're a utility provider (rather than the dinky little grid tied systems at peoples homes) they can provide reserve without following the grid, and black start reserves.Quote from: ludzinc on March 11, 2017, 01:17:29 amPumped hydro is still cheaper for bulk storage, but it has a limited slew rate around a minute in duration. So batteries can be a way to stabilise a grid lacking in turbine inertia. But thats a controversial topic as the counter argument from distributed generation is they cant have fast slews particularly when its geographically sparse:http://www.nrel.gov/docs/fy15osti/63045.pdf

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 03:52:58 am
content: Stoarage isn’t the major issue. They could install 10 GWH of batteries and it would make no difference. They need to get the energy into the grid and no-one is talking about the inverter requirements for this. Even if they installed 2 GW of inverters they they run into the issue of how they operate.Inverters for this style of application normally run in an on-grid mode. This means that there needs to be a grid voltage already present before the inverters will connect to the grid. If the grid voltage fails, as it did when the interconnect from Victoria went down a few months ago, then the inverters will also disconnect from the grid leaving a black out condition.The inverters can be configured to operate in an on-grid / off—grid mode. In this scenario they are generally connected on-grid and either charging the batteries or providing the grid with support power by discharging the batteries through the inverter. If the grid voltage fails the inverters will first turn off, but then a few seconds later turn back on in an off-grid mode. The caveat on this is that it requires that some very, very, very large switches be placed upstream to ensure that the grid cannot start up again through its normal supplies. The engineering design for such a scheme would require months to years of work before anyone touches it. The installation of such a scheme would require years, and cause massive disruption during the installation.For an engineering company Tesla make very good marketers.I wouldn’t trust Tesla to run a bath in 100 days.

author: Brumby
author_rank: Unknown
timestamp: March 11, 2017, 04:15:28 am
content: I'm not in the power industry - but there are a couple of things that I see wrong with that argument.Firstly, I don't see why there should be a turn-off and then turn-on staging with a noticeable gap between the two. UPS design has a whole range of experience behind it. Limiting your thinking on a grid powering inverter by looking at grid assisting systems is rather short sighted. They are not going to do something dumb like that.Secondly, I don't see why a traditional power system being brought back on line with an inverter powered grid would be any different to the grid powered by any other supply. They have to be brought into synchronisation before the supply and load are connected, whichever way you do it.Also, I would think there is a fairly well developed set of design criteria for such switching - with perhaps only some specific considerations for inverters.Someone correct me if I'm wrong.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 04:20:26 am
content: Quote from: sibeen on March 11, 2017, 01:15:23 amYou sound very certain of that, so you must know a lot about the SA power grid system and it's issues?Please explain in detail what the exact problems are in the SA grid, and what options are required to fix them. Please be very technically specific.

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 04:51:04 am
content: Quote from: EEVblog on March 11, 2017, 04:20:26 amDave, I don't need to know diddly about the SA grid. What Tesla have offered is batteries. They have claimed that they can fix the SA issues in 100 days. They haven't mentioned how they get this energy into the grid and that is the rub. They could supply an infinite amount of batteries but if that was feeding through a 1 MW inverter then it is going to do squat. Even if they had some very large inverters connected to the grid they still run into major issues.The grid in SA has very low inertia compared with a 'normal' power system. Traditionally grids have been run by very large generators which by their construction offer a large inertia and are slow to change their output. Wind and solar inverters on the other hand offer very little in the way of inertia and therefore systems with a high percentage of power through these devices are not as stable as their traditional cousins.AS4777 is the Australian standard for Grid connection of energy systems via inverters. Each Distribution Network Service Provider (DNSP) also have their own Embedded Generation Guidelines. These standards have very tight restrictions on how inverters are to operate when connected to the grid. To meet the AS requirements inverters must have very tight conditions upon which they operate and once these conditions are exceeded the inverter must disconnect form the grid. Generally you are looking at over voltage, under voltage, over frequency, under frequency, rate of change of frequency (ROCOF), vector shift etc. That's just for a bog standard 30 kW inverter. When you get to larger sizes even more restrictions and grid protection strategies are implemented. With a low inertia grid as soon as the Victorian interconnect hiccups then any connected inverters will turn off.From the opening link: "Billionaire Elon Musk has offered to fix South Australia's energy issues within 100 days, claiming that he would do it for free if he failed to meet the deadline"......."Rive told Australian news site AFR that the company could install the 100 to 300 megawatt per hour of battery storage that South Australia requires to stop power shortages and blackouts. Rive added that this could be achieved within 100 days"How can providing batteries do any of this? Without connection to the system they are boat anchors. Even connecting inverters doesn't solve the issue as the inverters will disconnect during a grid event..

author: Someone
author_rank: Super Contributor
timestamp: March 11, 2017, 04:55:46 am
content: Quote from: Brumby on March 11, 2017, 04:15:28 amYou're not wrong, most wind power installs are now inverter based and its the confusion about how they can be configured. Yes, an inverter can be configured to automatically cut out under different circumstances, or it can just spin away keeping the best sync it can with whatever its connected to. They dont do the second choice on most inverters for "safety" reasons around being able to quickly isolate parts of the grid when needed. These old ideas contributed to the SA failure as per their last report on the matter which was a surprising turnaround from their first report, so the wind power was available but not contributing:https://en.wikipedia.org/wiki/2016_South_Australian_blackout#Blackout

author: boffin
author_rank: Unknown
timestamp: March 11, 2017, 04:59:13 am
content: He did a smaller install on the Hawaiian island of Kauaihttp://www.independent.co.uk/news/science/tesla-is-powering-the-hawaiian-island-of-kauai-with-more-than-54000-solar-panels-and-its-giant-a7620991.html52 MWh Tesla Powerpack installation (272 units),so basically he's saying he'll install double that. It's doable, although he is a bit of a marketing whore.

author: Someone
author_rank: Super Contributor
timestamp: March 11, 2017, 05:10:13 am
content: Quote from: sibeen on March 11, 2017, 04:51:04 amIt wouldn't "fix" their problems of a lack of peak supply especially when the size of the supposed install is so small. We can see the magnitude of the grid from the figures we captured during the exciting event:https://www.eevblog.com/forum/chat/south-australia-has-no-power/msg1037216/#msg1037216To "fix" the grid you'd want something which can replace the 600MW interconnector demand from the eastern states, as they have their own supply challenges:https://www.eevblog.com/forum/chat/residents-asked-to-switch-off-appliances-between-1630-1830-today-due-to-heat/So as Dave summed up above, the scale of the installation is small and though useful its not a full solution.Quote from: sibeen on March 11, 2017, 04:51:04 amAs above thats a controversial claim disputed by proponents of distributed generation (with inverters!) the slew rates and stability of the grid are fine, if you let the inverters run with the same protocols as the existing generators then they're just as reliable if not more so.

author: mtdoc
author_rank: Super Contributor
timestamp: March 11, 2017, 05:11:42 am
content: Quote from: boffin on March 11, 2017, 04:59:13 amAnd he did an80 MWh install in Los Angeles- so stepping up to 100 MWH is not much of a stretch.It's always entertaining to see how anything Musk says or does gets some peoples panties in a knot. He's a master marketer for sure but he also breaks new ground and gets things done. The Musk haters must hate that.

author: Brumby
author_rank: Unknown
timestamp: March 11, 2017, 05:35:13 am
content: Quote from: sibeen on March 11, 2017, 04:51:04 amBlah... blah... blah...Standards are not immutable. They are dynamic beasts that can be - and are - altered to accommodate new technology and requirements. Their purpose is to ensure harmony - not to stifle progress.I would not be worried about what inverters Elon Musk would want to use. It's not as if they are untested technology. If there are any conflicts between those units, the existing infrastructure and the AS rule book, I'm sure they can and will be worked out.That is, of course, if merit is seen in the proposition and the idea of going down that path is entertained.

author: ludzinc
author_rank: Unknown
timestamp: March 11, 2017, 05:49:31 am
content: At least people are now starting to talk about Grid Level Storage.I'd personally like to see governments stop subsidising wind / solar and start investing in storage solutions.First country to crack that nut gets to roll out (and profit from) the benefits worldwide!

author: Someone
author_rank: Super Contributor
timestamp: March 11, 2017, 05:50:41 am
content: Quote from: Brumby on March 11, 2017, 05:35:13 amAlthough that standard has seen its scope widened multiple times, as of now its only forsystemsunder 200kVA. So yeah, not actually relevant.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 05:54:32 am
content: Quote from: sibeen on March 11, 2017, 04:51:04 amAnd you don't.QuoteDid they? Really? I'm thinking it didn't quite go down that way.QuoteNope, that's the headline made up by the newspaper. Elon has promised tosupply100+MWh of battery storage capacity and install it within 100 days or it's free. He has made precisely zero claims that it will fix specific problems with the SA grid.QuoteOk, so whoactuallysaid that SA requires 100 to 300 megawatt per hour of battery storage to fix problems? Who came up with that number? Was it Tesla? Really? Have they looked into the intricacies of the system themselves and determined on their own that that is what is required to fix the issues? Or have they simply heard from someone else (who?) that 100-300MWh would do the trick? In which case of course they are going to run with that.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 05:59:46 am
content: Quote from: ludzinc on March 11, 2017, 05:49:31 amI like this solution:

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 06:02:25 am
content: Quote from: EEVblog on March 11, 2017, 05:54:32 amDid they? Really? I'm thinking it didn't quite go down that way.Quote

author: hendorog
author_rank: Super Contributor
timestamp: March 11, 2017, 06:07:44 am
content: We're already testing a little one for you chaps.https://www.vector.co.nz/innovation-news/video-tesla-powerpack-launch-at-glen-innesThe vid is worth watching. It has an annotated timelapse of the build.AFAIK this was put in to avoid having to spend money upgrading a substation.So I think the standards question is covered as NZ will have done all that work for ya.

author: EEVblog
author_rank: Unknown
timestamp: March 11, 2017, 06:12:34 am
content: This reminds me, I really do have to get around to getting that home storage solution.

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 06:16:03 am
content: Quote from: Brumby on March 11, 2017, 04:15:28 amInverters that are designed for on/off grid mode of operation use different operation modes for each. When grid connected the inverter operates to control the power and the kVAR from the output. When in an off grid mode the inverter controls the output voltage and frequency. When transitioning between the two modes there is a break in power, albeit that this may only be a few cycles with some modern inverters. It is normally the switching of the islanding component (circuit breaker, contactor etc) that increases this timinmg.Quote from: Brumby on March 11, 2017, 04:15:28 amThe inverter system needs to be isolated (islanded) from the grid system. In the case of SA if you are going to power the state from the inverters then the state would be required to be islanded or you're then trying to feed eastern seaboard as well. The engineering design and construction work to get that done is huge.

author: Brumby
author_rank: Unknown
timestamp: March 11, 2017, 06:37:27 am
content: Quote from: sibeen on March 11, 2017, 06:16:03 amHow is this any different to existing infrastructure?There have to be isolation points already in place .... surely.

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 06:39:23 am
content: Quote from: hendorog on March 11, 2017, 06:07:44 amYes, it is very nice. It is a 1 MW, 2.4 MWH on-grid only system. The standard in question (AS/NZS 4777.2:2015) does indeed cover New Zealand and this installation will have been covered off under that standard.

author: Someone
author_rank: Super Contributor
timestamp: March 11, 2017, 06:58:55 am
content: Quote from: Brumby on March 11, 2017, 06:37:27 amIts no different at all, inverter based infrastructure can be added just like any other and is more flexible in its ability to be controlled. The existing inertial systems don't work inherently and failed to operate as expected during another SA disconnect:https://www.aemo.com.au/-/media/Files/Electricity/NEM/Market_Notices_and_Events/Power_System_Incident_Reports/2017/Final-report---SA-separation-event-1-December-2016.pdfBut completely islanded the grid continued on fine after the initial load shedding to support their limited generation capacity.Quote

author: sibeen
author_rank: Frequent Contributor
timestamp: March 11, 2017, 07:12:07 am
content: Quote from: Someone on March 11, 2017, 06:58:55 amI'd agree totally with all of that. I'd just like to know where the inverters are coming from for the Tesla system and what size they'll be, and how quickly it will take to install them.

author: AndyC_772
author_rank: Super Contributor
timestamp: March 11, 2017, 10:53:43 am
content: In any other company, this would be reported as:- out-of-touch MD makes ridiculous promise to customers without consulting technical staff- engineers and technicians are told what they have to do, and by when-Seems Tesla have more credibility than most. Will be interesting to see how, and if, they can pull it off.

author: ludzinc
author_rank: Unknown
timestamp: March 11, 2017, 11:59:00 am
content: Quote from: EEVblog on March 11, 2017, 06:12:34 amI'm in SA - so home storage is something I'd love to consider.Not to reduce my bill, but to give me power when all the other lights go off.Mind you cash flow is problematic at the moment (with any luck it will ease up once the three kids finish school, lol) - so I'll be comparing battery systems with a plain old fashioned Diesel genny....Should be an interesting exercise!In other news, at work we have a 'remote site' with demanding power surges. Powers that been have been looking into PV / Battery / Flywheel solutions there. The latter is quite interesting tech!

author: nctnico
author_rank: Super Contributor
timestamp: March 11, 2017, 12:39:34 pm
content: Quote from: EEVblog on March 11, 2017, 06:12:34 amGood idea because that is most likely the solution Musk is going to provide! Home storage is the only solution you can implement in 100 days (a little over 3 months). Permits, erecting a building, grid connection, etc won't be finished in that time.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: March 11, 2017, 01:56:51 pm
content: Quote from: mtdoc on March 11, 2017, 05:11:42 amhttps://www.nytimes.com/2017/01/30/business/energy-environment/battery-storage-tesla-california.html?_r=0I agree, read this article, it seems that all they need to do is scale it up to 100MWh.It's obviously well within Teslas capability to deliver a similar system in the 100 day time frame.As far as the grid connection specifics, ie. location, transformers, regulation changes. I guess that will need government input, so it will be hard to get that sorted in the timeframe.I'm sure the SA government will be keen though to show up the Federals so they will be cracking the whip.

author: BrianHG
author_rank: Super Contributor
timestamp: March 11, 2017, 02:19:42 pm
content: Quote from: EEVblog on March 11, 2017, 05:59:46 amYou loose energy due to friction in both directions, charge and discharge.I've heard of huge fly-wheels in a vacuum sitting on magnetic bearings, which both removes the bulk mass from the friction for heavy duty shaft & bearings & the magnetic's are also part of the motor/generator core. --- I need to hunt down the PBS Nova YT video it was part of ---

author: nctnico
author_rank: Super Contributor
timestamp: March 11, 2017, 04:22:58 pm
content: Quote from: BrianHG on March 11, 2017, 02:19:42 pmThat is true for any energy storage system. I watched a bit of the video and I like it because it is very simple and flexible to install. You could even build it underground.

author: free_electron
author_rank: Super Contributor
timestamp: March 11, 2017, 05:03:02 pm
content: Quote from: mtdoc on March 11, 2017, 05:11:42 amAnd an installation in american samoa.By the way, the Kauai installation has an inverter capacity of 13 megawatt.The installation in california has a 20 Megawatt inverter with 80Megawatt/h storage capacity.

author: station240
author_rank: Unknown
timestamp: March 12, 2017, 02:15:02 pm
content: Each Powerpack 2 is 210kWh (AC) which I assume includes the inverter efficiencies.To get 100MWh you simply need 477 of these cabinets for a combined weight of 774 metric tons.Plus inverters, which Tesla now makes themselves.Aside from the transmission towers falling over incident, SA's power problems have been caused by the start up times of gas/coal fired power stations (as the costs of leaving them running just in case is too high), or by moronic management issue from the national power grid (eg not reading the weather forecasts properly). Even if this Tesla battery farm can only power the grid for a limited amount of time, it's enough to get another generator up to speed.I assume Tesla plan to charter their own container ship to move all this equipment.

author: SeanB
author_rank: Super Contributor
timestamp: March 12, 2017, 03:37:39 pm
content: 2 747 cargo flights to bring over the basic install infrastructure, and the plant cabling and basic racking, with a team of installers either local or from the USA to do the plant layout, placing of all the equipment in a supplied building, with the heavy stuff coming on a chartered container ship otherwise deadheading back across the Pacific, so low transport cost, and a paid diversion for them and yet more deadheading containers back with the rest, estimated that they will take 40 days to get there, enough to have the infrastructure laid out and ready for the install. Then the install will probably be 30 days to do, with the remaining 30 days for final commissioning of the system in stages to full operation.You probably will find there will be a further 2 flights to do the unanticipated stuff, though those probably will be small enough to fit in as regular air cargo instead, Miami Rick will not be having 2 day long flights to deliver the cargo via Japan.

author: Koen
author_rank: Frequent Contributor
timestamp: March 12, 2017, 04:15:41 pm
content: The cargo planes could also be painted "USAID" so the locals know who's coming to their rescue !

author: SeanB
author_rank: Super Contributor
timestamp: March 12, 2017, 04:48:07 pm
content: [Quote from: Koen on March 12, 2017, 04:15:41 pmJust the regular Acme Air livery will be fine......

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: March 14, 2017, 02:48:12 am
content: The SA government has a plan.http://www.smh.com.au/business/energy/south-australia-build-battery-gas-plant-under-energy-plan-20170314-guxid7.html

author: Avacee
author_rank: Unknown
timestamp: November 23, 2017, 09:11:08 am
content: Appears the The Great South Australia Battery is going to be installed on timehttp://www.bbc.co.uk/news/business-42090991http://www.smh.com.au/business/energy/elon-musks-giant-battery-is-set-for-testing-in-south-australia-20171123-gzrbru.html

author: VK5RC
author_rank: Unknown
timestamp: November 23, 2017, 11:00:04 am
content: Bugger! I was hoping it was going to be a day lateSeriously could be worth a visit - I think they were going to include a visitor centre etc.Robert (I live in Adelaide , Sth Aust)http://www.abc.net.au/news/2017-11-23/worlds-most-powerful-lithium-ion-battery-finished-in-sa/9183868

author: Brumby
author_rank: Unknown
timestamp: November 23, 2017, 01:06:11 pm
content: Quote from: VK5RC on November 23, 2017, 11:00:04 amVK5...?I never would have guessed.

author: vk6zgo
author_rank: Super Contributor
timestamp: November 23, 2017, 10:46:45 pm
content: Quote from: Brumby on November 23, 2017, 01:06:11 pmMeaningless to most people these days.

author: EEVblog
author_rank: Unknown
timestamp: November 24, 2017, 12:01:54 am
content: I want to head over there to check it out, but flat out at the moment.

author: mtdoc
author_rank: Super Contributor
timestamp: November 24, 2017, 12:20:24 am
content: Quote from: EEVblog on November 24, 2017, 12:01:54 amYes, please do. A video tour of the facility would be awesome

author: cdev
author_rank: Super Contributor
timestamp: November 24, 2017, 12:45:11 am
content: What about compressed air? Compressed air's energy lasts indefinitely and I don't think it would be that expensive in terms of waste energy to store and extract it.

author: coppice
author_rank: Super Contributor
timestamp: November 24, 2017, 01:12:11 am
content: Quote from: cdev on November 24, 2017, 12:45:11 amIf you compress air both the pressure and temperature rises. If you want efficient storage you need to capture both. With enough care about sealing you can keep the pressure forever. Storing the heat for a long time tends to be a tougher problem.

author: cdev
author_rank: Super Contributor
timestamp: November 24, 2017, 01:53:04 am
content: Maybe foam insulation would be both cheap and good enough? It doesn't have to be perfect. If you could even get 75% efficiency that would be better than nothing. Also compressed air storage might last longer than batteries in terms of charge recharge cycles.

author: coppice
author_rank: Super Contributor
timestamp: November 24, 2017, 02:06:56 am
content: Quote from: cdev on November 24, 2017, 01:53:04 amInsulation could be enough to make a great short term gas compression storage system, say for spreading solar energy generated during daylight to cover the dark hours. There seem to be several groups working on this. You were talking about indefinite storage, though. If you want to store, say, 10 days worth of energy to cover a becalmed period when wind farms are out of action (a period which is not that rare in many parts of the world) you'd need some really good insulation not to lose a lot of the stored energy.

author: Someone
author_rank: Super Contributor
timestamp: November 24, 2017, 02:58:30 am
content: There are times and places when even a 20-30% efficiency storage system would be still useful and viable but thats only the electrical efficiency, there is real value in the heat and cold produced in the cycles which can be captured in more complex HVAC or refrigeration systems as currently done in "trigeneration". The simple case would be a fridge which uses its existing cycle with some storage to best use available tariffs or renewable power availability.

author: coppice
author_rank: Super Contributor
timestamp: November 24, 2017, 03:21:11 am
content: Quote from: Someone on November 24, 2017, 02:58:30 amIf your requirement is to store enough energy for an unusual event, efficiency in itself is not a big issue, because you don't have to take that efficiency hit very often. The real issue there is how much low efficiency blows up the size and cost of the system. If you could find a scheme that is compact and cheap but very inefficient it could provide a viable storage scheme for for riding over these unusual long low production events.If you are looking at a storage system to ride over daily periods of low generation you really need high electrical efficiency. If you have poor electrical efficiency, and a lot of heat/cold coming out of the system daily, your chances of the amount of heat/cold being a good match for what you can use are going to be pretty low in most places.

author: Someone
author_rank: Super Contributor
timestamp: November 24, 2017, 03:46:34 am
content: Quote from: coppice on November 24, 2017, 03:21:11 amIts all down to cost, at 20-30% efficiency a system could still be turning a profit against current solar feed in rates if it was a very small incremental cost (refrigerator example). Larger systems for households or businesses make more sense because there are (in most developed nations) sustained demands for hot water and cold storage every single day of the year, so we have already use for the thermal cycling. Integrate this with central HVAC and it wouldn't need to be a substantial size increase compared to existing systems in use and most houses have plenty of spare room for utilities.

author: coppice
author_rank: Super Contributor
timestamp: November 24, 2017, 03:59:31 am
content: Quote from: Someone on November 24, 2017, 03:46:34 amAre you talking about big centralised storage systems, or local domestic ones? If we had an inefficient storage scheme compact enough to have in every home, quite a bit of the waste heat could probably be used for domestic hot water. If you are talking about centralised systems, we already have large centralised sources of masses of waste heat in current power stations. It seldom works out very effective to use this for domestic hot water and heating applications. Instead, it gets dissipated into the atmosphere in huge cooling towers.

author: jonovid
author_rank: Super Contributor
timestamp: November 24, 2017, 04:55:14 am
content: it all started with privatization of the power networks and the Al Gore's BS movie. one power outage a yr is ok. if its the weather.so why all the $ storage for uninterruptable power to stop interruptions in the CBD and its problems. = politicians in the darkbut for most of us households can live with the odd power outage, if the power is cheap.another white elephant from the politicians that may be responsible for power outages.is the unneeded $1.83 billion adelaide water desalination plant or sea water reverse osmosis desalination plant.uses 3.47 to 3.70 kilowatt-hours of electricity per kilolitre of water produced.that it needs its own electricity supply sub-station.

author: 3roomlab
author_rank: Frequent Contributor
timestamp: February 16, 2018, 04:00:17 pm
content: I just happen to see this newshttp://www.independent.co.uk/news/world/australasia/elon-musk-tesla-batteries-australia-homes-virtual-power-plants-free-solar-panels-a8196656.htmlso add some free solar panels and power packs, and sell the electricity to cover the free costs of installation. hmmmm yum?

author: VK5RC
author_rank: Unknown
timestamp: February 18, 2018, 11:28:33 am
content: The price of electricity here in Adelaide is so expensive, 43c/kWhr is a 'good' rate. Peak consumption is also often in summer (air conditioning) we have a typical hot, dry and cloudless summer. Our recently installed 8kW system (with good panels and Fronius inverter) should pay for itself in 4-5years. Feed-in rates are about 16c/kWhr. eg in Jan we generated about 1.40MWhr.

author: fubar.gr
author_rank: Unknown
timestamp: February 18, 2018, 11:30:43 pm
content: Electricity prices in Australia are crazy.It's one of the few places in the world that storage batteries make economic sense.

author: gildasd
author_rank: Frequent Contributor
timestamp: February 19, 2018, 08:21:31 am
content: https://www.theguardian.com/technology/2018/feb/06/how-teslas-big-battery-is-bringing-australias-gas-cartel-to-heelWas this an expected consequence?

author: Brumby
author_rank: Unknown
timestamp: February 19, 2018, 03:18:46 pm
content: I'm sure the players in the game knew exactly what the potential was. Whether that was adequately and accurately reported by the media - and how widely that was distributed is another question.As - I would hope - that they have considered scenarios where the batteries are partially available or not available at all for whatever reason.I'm no power guru - but it would seem risk management of continuity of supply would have to be one of the major foci of the industry.