I knew Danielle Fong from Lightsail Energy, folded in 2016, and at that time compressed air seemed like a great solution especially for LatAm that needed robust low cost batteries for critical infrastructure (like hospitals) on an unreliable power grid. https://en.wikipedia.org/wiki/Danielle_Fong
Would be great to see this technology reach maturity!
I too was wondering that as the ideal gas law states that PV = nRT. When you compress a gas it gets hotter, conversely, allowing it to decompress cools it. I assume they store the heat energy...
CAES has lower efficiency, probably closer to 70% and only if you use something to reheat the air. (Compressed air loses temperature and needs an external source of heat to restore it to full volume)
Even if you use natural gas as a reheating element, the compressed air stores a significant amount of energy and is doing the majority of the work.
If you ignore efficiency then you stop making a profit pretty quickly. You can solely focus all you want on cost; sooner or later efficiency will make you pay.
Goldman wouldn't be making that kind of an investment if they didn't have a handle on both parts of the equation. Indeed efficiency (dealing with losses from seepage) have been the nut that hasn't been cracked with compressed air storage; these guys seem to have an economical (efficient) way to deal with that problem. If true, then they really are worthy of Goldman's investment.
This brings to mind the other post about the Amish that's on today's front page. I believe the Amish sometimes use compressed air as an alternative form of power.
I read an article in a woodworking magazine about how one Amish woodworking shop was built to avoid using electricity. The whole shop ran off a stationary diesel engine driving a shaft in a floor trench and belt drove the larger stationary machinery like band saws, table saws, planers, drill presses, joiners and so on. But what about hand tools? A large belt driven air compressor off the diesel engine handled a myriad of air power tools like drills, orbital sanders, buffers and all that. Really neat setup.
Also adds a ton of pollution from using (often old and poorly maintained) Diesel engines in the name of avoiding the electric grid. Adding to that, compressed air is a much less efficient source of power than using electricity directly.
Yes, but air tools can be really nice to use,esp for grinding, cutting, sanding operations. For one, you can press/dig hard enough to bog or stop the tool and nothing hapoens - you just pick it uo and it speeds back uo again - do that with an electric tool and you'll have a dead motor paperweight real soon.
Air tools can also be lighter and no worries abt damaging the cord or carrying the battery.
Many good air tools can also have a better feel, especially if you can control the air flow trigger.
(I don't have a bias either way, use both in my shop, but just wanted to point out that both have advantages)
I agree - air tools are awesome in some cases, although modern brushless tools are often competitive if not superior to air tools compared to how things were a decade ago.
My complaint, really, is just how selfish it is to go out of your way to use a dirty energy source as a workaround for limits in your personal belief system.
Yes, I've also noticed that the new brushless motor tools are often great!
And yes, using diesel to power your compressor on a regular (non-emergency) is more than a bit wasteful.
I totally get their insistence on staying off-grid, and it is good to read that they seem to be positive towards solar, so we can hope that takes over soon! From the bits I've read about their ethos, it certainly should have the advantage of further reduced dependency on outside systems, in this case, a one-off purchase of solar panels & kit will eliminate ongoing dependence on the entire fossil fuel supply chain.
My father once told me that a lot of machine shops used to be set up that way, except that the powered shaft ran along the ceiling instead of in a floor trench. "Just throw a belt up over the shaft" and attach it to the machine you want to use, was how he described it.
I don't know if it's still there, but there used to be a fancy restaurant in the Eastlake part of Seattle that had started out that way, and still had the old Art Deco-ish drive shaft running around the ceiling. It was a neat touch point when I saw it and remembered my dad's description from years before.
My understanding is that this paradigm was incredibly dangerous, with a lot of workers losing hands and arms in accidents. Turning on or off a given machine involved physically putting the belt on or pulling it off, and you could easily get caught in it. A very clever system for the technology of the day, but it's good we don't use it anymore, at least without more advanced safety mechanisms and practices.
I would have assumed they would have clutches so that individual machines could be disengaged. The large open belts running up to the drive shaft on the ceiling were dangerous regardless.
I thought the whole schtick of the Amish was that they don't allow themselves to become reliant on technology, electricity just being an example. I doubt that Amish guy knows how to rebuild that engine should it fail.
They don't believe in having technology in the home. Most Amish are perfectly willing to work with modern equipment for their shops and businesses. Go by an Amish milking shed anywhere in the country--as my dad would say 'they're lit up like a shit house in the fog'. Electric lights from one end to the other with modern milkers inside.
The Amish only allow technology that they think will improve their lives. Many have cell phones, but don't use Facebook for example. I'd also bet he could repair the engine if he needed to.
This is basically how most indistrial setups was before engines and motors became a commodity. You had water wheels as your main power source, from which other tools was driven via belts and gears.
Later the waterwheel was replaced by an electric motor or a fuel powered engine - but still built around just one source of power, with elaborate setups to drive different tools. With the added benefits you could build factories and workshops outside main water sources.
There is a wonderful museum in Windsor Vermont called American Precision Museum which still has the original overhead shaft and pulley system along with machinery. Went there in the early 90's as a kid and they did mention that it was converted to electric and the motors were still working supposedly.
The Edison museum in Orange NJ also has such a preserved shop setup but electric driven by one or two big motors on an elevated platform.
After watching it, I now understand that they aren't flooding the entire borehole, but rather are building a smaller high-pressure chamber at the bottom. The chamber is connected to pipes to a surface reservoir. When air is pumped into the chamber, it displaces water up toward the surface. When generating, the water flows back into the subsurface chambers, forcing out the high pressured air.
Not much, technologically this is a conventional mine project, only that you mine air volume instead of rock and have to take care of the cavern being reasonably airtight afterwards.
The video is from 2015, and says it was a 2 year pilot project. Do you know if there are there any updates on how the project went? Is it still operational? Did they build any more?
you don't have to build those caverns as they already exist and we have extracted gas and liquids from them, also the volume should be already known as we know how much we pumped out (unless it's an old site)
I don't have specific numbers, but in other batteries of this type, the length of storage time before discharge affects the efficiency. Heat stored from compression is lost over time.
I was curious about that as well. I think it's best application would be to compensate for large amounts of rising and falling generation from solar grids, that way the cycle is daily. Being quick to come online and meet demand makes it good for maintaining grid stability at a much lower cost as well, like the Hornsdale Power Reserve facility https://hornsdalepowerreserve.com.au/.
what would be the benefit to it being heated by the earth during storage?
all the temperature management here looks to just be counteracting the temperature changes that naturally occur when you compress or expand a gas. i imagine if you compressed it and then pumped hot air into water-filled caverns you'd get some negative effects of thermal shock.
Hot air should have higher pressure, so theoretically you could get more displacement. But your pumps also have to work harder to create a pressure differential. Hard to say which effect would be bigger.
I'm guessing not. Earth's heat is way lower down. Think of a cave: always cold. I think what's going on is they're taking the heat out and storing it more efficiently than just dumping it down the ground, where (1) it would leak away, representing energy loss, and (2) as it leaks away, the air would lose pressure. (It would leak away b/c it's harder to insulate an entire mine, basically.) So, they pull it out ahead of time and put it back in when they decompress the air (which I think would add pressure back in due to heating a gas and maybe reduce problems caused by super-chilling other plant hardware? Anyway, seems fitting to add back what you took out if you're shooting for a closed system.)
Naive question but couldn't our forerunners who otherwise succumbed to cold in harsher climates have exploited this fact to dig subterranean villages and towns?
What's the element I'm missing as to why they didn't?
Difficulty of digging with the tools they had, inability to stabilize the structure to prevent cave-ins, lack of pumps to remove accumulating water, insufficient ventilation and filtration technology/unable to deal with poison gases, inability to light their environment without contributing to the poor air quality, difficulty accessing resources like food and clean water, lack of desire to live in a damp, dusty hole.
Pre-industrial holes may collapse long before you reach -100 meters. Even -5 meters is a challenge in certain places.
Also, digging (or rather drilling) in bedrock is hard without motorized equipment and good steel.
Also, supplying fresh air down there is a problem.
Also, preventing the mine from flooding is usually a huge problem.
Mining is hard and a lot of people lost their lives doing that. That said, if your only intent is to get a bit warmer, you may basically try a good cave. Caves tend to have temperatures above freezing for the whole year.
More like, ever tried to dig down more than a foot or two? Unless you have really soft ground, even a good steel spade and shovel aren't any guarantee of success. Powered augers are often needed to make holes for fence posts, etc.
Also for example Finland can be at least in north considered harsh climate. But these are also areas that suffered of ice age that scrapped most of the softer rocks away leaving only the tougher stuff like granite. Which makes digging very difficult, specially pre-industrial times.
Do you have a source for that increase? I was not able to find it. Seems very suspect considering that the earths outer crust is approximately 20 to 30 miles thick. Are you suggesting that if we go approximately halfway through the outer crust, say 15 miles, the temperature is going to be 725 degrees warmer than surface temp?
Not sure about the rate per-mile, but literally it's that hot, yes, but not even 15 miles. Just down 5-7km under the oceans, for example at the Mohorovičić discontinuity the temp ranges from 392 to 752F.
Under the ocean is already much, MUCH closer however to the mantle. Oceanic crust is drastically thinner than the land we walk on.
In the Nat Geo article they quote a mine in South Africa reaching up to 55C (131 F) at the bottom and the mine is 4km deep. At a rate 3 degrees Celsius per 100m it should be 120 degrees Celsius over ambient. Which obviously does not add up.
> The heat is transferred from the interior towards the
surface mostly by conduction, and this conductive
heat flow makes temperature rise with increasing
depth in the crust on average 25-30°C/km
Have you been in a cave? They're chilly, usually around 50F, year round. IIRC those "deep mines" are a LOT deeper than any compressed air storage system is likely to be.
This comment is an example of why I’ve become skeptical of the downvote button. It sounds like people read it, knew better, and politely pointed out that it was incorrect.
Everyone who might have shared the same misapprehension learned something and the parent wasn’t being an asshole.
Yes, when considered along with the corrective responses, it adds to the discussion. This is why it shouldn't be flagged and removed. On the other hand, it's factually wrong and would be misleading if people were to trust the claims uncritically, which I think justifies a downvote. Keeping it visible but lower on the page and showing it in gray seems like a pretty good compromise. Can you suggest a better way of giving more prominence to correct information? Or do you think that's not the right priority for the site?
Side question - do you need to reach a certain level of membership with HN to see the downvote button? I may be missing something, but seems that's only allowed for certain individuals.
Didn't downvote, but I am not a big fan of simply making stuff up on the fly as response. I've met my share of people who rather go this route than put in a 5sec Google search or simply admit they don't know something, and I try to avoid them.
"Looked the temp gradients up, after 50ft, temp of the earth is 50F, and raises one degree F every 60ft." (So, at 300 feet, 54 degrees; at 500, 57.5 degrees.)
«The temperature on average is in the 50s, but you still sweat an enormous amount when you start laboring.“ - Alan Bates, working in the coal mines of Letcher County, Kentucky.»
The big question is how on earth are they digging out these caverns? That seems like a huge challenge, given that they're so far underground. Everything else seems relatively straightforward
I had a similar idea for repurposing an old mining operation. You take a closed gold, uranium or copper mine which is 1000-2000 meters deep. You create a nuclear rector at the bottom with "fire and forget" design. Only robots can do the maintenance. After 60 years you disable it, pour concrete into the shaft and move to the next location. If it melts, who cares? It's not gonna poison water supply.
Why was this not built before? I have no idea. Maybe robots are essential, we didn't have deep enough mines that were abandoned, energy was cheaper, no push for no emissions, it's not economical, other risks.
You need a hot and cold reservoir to generate power. Where is the heat going to go? This is why power plants are often built on rivers or near the ocean.
inb4: not a specialist. AFAIR remote control robots were tried when Chernobyl disaster was being cleared up, and the radiation destroyed the electronics. But perhaps the shielding technologies progressed enough to mitigate that.
Having nuclear stuff underground requires extremely precise geological surveys, so that the stuff does not wind up in aquifer.
In France we’re storing highly radioactive items underground. Here is how dissipation works:
- After a few dozen years, the concrete is expected to breach,
- Radioactive atoms mix up with soil and dissipate both upwards and downwards, mostly thanks to water,
- After 400 years and for thousands of years, they reach the surface, where they should be diluted enough to not be dangerous,
So I guess having badly contained radioactive containers would be much worse.
One thing to remember is that pressure underground is extremely high (stone weighs a lot more than water, and light rock tends to “float” onto denser rock). If a melted reactor were squeezed, it would spread materials into the soil much quicker.
The footprint of a nuclear power plant is pretty huge. That machinery is generally not optional even if doing a "fire and forget" design. Underground space would come at a premium cost, likely far more than could be saved on reactor design.
Also nuclear power plants obviously generate an absolutely massive amount of heat that needs to be dissipated, a task that would be difficult and expensive underground.
A similar thing is done for natural gas storage. A well will be drilled into a rock dome that lies atop a layer of saltwater-saturated sandstone. Gas is then pumped into it, displacing the water, and then can be withdrawn later.
> Goldman Sachs agreed and invested $250 million from its private equity division.
Maybe they're referring to Goldman Sachs Capital partners which has 39.9B[0] under management which means this is 0.62% of their portfolio. In a totally chalk and cheese comparison that would be having 200k in your 401k and taking a $1,250 position in a stock, which isn't nothing but is a pretty small bet, I agree. Curious though if I'm guessing the part of GS correctly; I have no idea how they're structured and just spent like three minutes searching.
GS isn't known for their scientific prowess - signal that they believe there is money in large scale ESS. Not sure if it's validating the technology at all though. Compressed air has been around for a long time at this point.
Who is known for their scientific prowess? A16z and with sprawling investments in web3? Capital is capital. We should be cheering on these types of investments regardless. Electric motors have been around for a looong time as well..
The VC and investment world in energy technology is quite different then the A16z and traditional VC world or financial heavyweights.
Having had GS invest in companies in the energy tech space in the past and having not particularly great success - I wouldn't think this is a strong signal. More that the financial heavyweights think there is action and they want to get in.
Goldman has army of analysts that are covering the field. Many many more than Even VCs that specialize in it. I would definitely write them off when it comes to smart investing.
Put another way it sounds like a corporate investor or VC into an industry they know a little about but have heard good things. Goldman Sachs is not known to be a good energy investor. Who knows maybe now they are.
Would energy storage not be a good use of that money? Society is facing a large problem: climate change. One way to reduce the impact of climate change is to use renewable energy like solar and wind. Solar and wind have a big problem; they can't be turned on and off. That means to displace fossil fuels, we need to store energy when it's sunny and windy, and release that energy when it's not. Hence, things like compressed air energy storage. This is the kind of technology that can prevent entire cities from disappearing over the next 100 years. Seems pretty valuable to me.
Small nitpick. Wind can be turned off. The turbines can be equipped with brakes to stop power generation in case of oversupply, in addition to other uses.
Appropriate natural caverns do exist, but are not common. One of the main differentiating factor between this approach and others is that they drill a man-made borehole rather than depending on finding a pre-existing cavern.
Cavallo, A. (2005). Controllable and affordable utility-scale electricity from
intermittent wind resources and compressed air energy storage (CAES).
Science Direct.
Well, yeah, this is in the opening of the article:
> It updates a long-standing technology that never took off for electrical storage.
There is/was plant operational since 1970s in Germany[1], which looks similar to the Wired article, but different from some other solutions posted in comments. Missing some parts perhaps to be viable.
How does the economics of this look like, and how do they intended to get back the investment. If its to buy low when wind/solar production is high and sell when production is low, what will the cost per watt be? If its subsidies, how much will this cost the government?
The article seem to mostly describe this as a technology project to test the technology at scale, but they do also mention profits. Is the basic premise of buy low sell high, exclusively on renewables, enough to offset the cost from energy conversion, building, staff and other costs, and if so, by what degree compared to other method to produce energy? When is it estimated to have paid its initial investment?
Energy storage if you want to rely solely on renewable energy sources is THE KEY to making that even remotely feasible.
Current solar and wind renewables are NOT predictable nor reliable for sustained power generation. With Coal, Natural Gas, Nuclear and Hydro you can generate power on demand, no matter what the environment is doing. Well, Hydro in the west is getting dicey with the drought - but even that is far more stable than wind/sun which can vary wildly week to week, day to day or even hour to hour.
That's why technology like this is so exciting. If you can look at the average production of a renewable over a month, then within a year the peak month, then look at the worst months, then have enough storage to cover a percentage of a peak month based off the hedge of the worst month then you are getting to a point where a solar farm isn't just an opportunistic source of power based on how much the sun is shining, but a reliable energy source that can be counted on whether the sun is shining or not.
Same for wind farms.
Energy storage is crucial if we seriously want to transition to renewables and hence the investment from Goldman Sachs.
If this company is even remotely successful in actually delivering then $250M is a pittance to what they will receive back in the long term.
There are also a lot of unused/abandoned underground structures - from various wells that are now dry of the resource they were originally drilled for to mines that are no longer productive. The problem has been sealing them from seepage so you don't loose your stored air - this article was light on details but that seems to be this companies claim to fame. They seem to have found economical ways to deal with those issues - enough to convince the boffins at Goldman Sachs they are worthy of investment. I guarantee you Goldman is not just tossing out money willy-nilley without performing some significant due diligence!
The question is still economics. At minimum the cost per watt/h need to be cheaper than to build a nuclear plant and have it run when demand exceed supply from renewables. Is this true for compressed air?
When people discuss green hydro as a storage solution the numbers so far, from what I have managed to interpret, is around 3-5 times that off nuclear for the same amount of energy delivered. It is still technically possible to make a profit given enough subsidies and time, and it get much more economically if the hydrogen can be used directly in the production chain like steel and fertilizer. Right now there are a steel foundry in Sweden testing the technology and economics doing that, through I don't know how much subsidies and tax reductions were involved.
Which all means the question about economics remains. There are many alternatives to fossil fuels but the primary question everyone debates is the issue of price. Without a price per watt/h or a time frame for when the investment get repaid its impossible to separate the practical from impractical, and the subsidy question is very relevant when discussing this on a national level.
I really enjoy learning about quirky ways to "store" energy, there is also one case that allows "storing" of energy by pushing massive concrete blocks uphill and when energy is needed, blocks simply slide down and generate energy. Not sure if this can be called "Storing" though.
Curiously there's a second article discussing compressed air energy on the front-page of Hacker News at the moment - it's about the Amish and their hacker mentality [0]. There's a beautiful discontinuity between one of the more tech-savvy old-guard banks and the technology-careful Amish adopting the same technology.
They claim 1m in revenue from their existing product which is:
"1.75 megawatts (MW) of peak power output; a 2.2 MW charge rating; and 10+ megawatt-hours (MWh) of storage capacity"
How does that equal 1m in revenue? You have to pay to charge your air-battery during low-cost hours and then discharge it during high cost hours to make the difference in revenue.
The issue is, you can buy 2 megawatts of power 24/7 at average datacenter energy pricing (~5c/kwh) for $2400/day or 876k/year. Who is paying more than that for less energy and only at certain hours?
Is there some energy company somewhere that sells power during the day at like 50c/kwh and 1c/kwh at night???
These kinds of utility-run storage facilities usually buy and sell on the wholesale spot market, which swings much more than retail prices do. Somewhat similar economics to gas "peaker" plants, which only fire up when supply is tight and prices spike, making it economical to run a higher-cost generator.
The Hydrostor plant is in Ontario. Here's an archive of hourly spot-market electricity prices there (in dollars per MWh): http://reports.ieso.ca/public/PriceHOEPPredispOR/. So far in 2022, prices have been as low as $0.00/MWh (during a few hours overnight on Jan 5) and as high as $230.87/MWh (during the morning of Jan 11). In 2021, hourly average prices even exceeded $1000/MWh ($1/kWh) twice, on March 28 and October 10.
I would need to see the math, because nothing adds up to even 1/10th of their claimed revenue. Best case, they bought 10mwh on jan 5th and sold it at the perfect time on jan 11th. This would give them 2k in revenue in 6 days.
Wheres the rest? And what about if you cant nostradamus predict the best times to buy and sell?
Sometimes utilities only need a few minutes of power to cover small gaps while ramping up/down powerplants, or if a cloud passes over a solar generation facility. Since these volumes are very small but critical, the effective price per MWH is extremely high.
When Tesla did their grid scale battery installation in Australia, this is how they made their money. Not via energy arbitrage, but with selling frequency response services. I have no idea if this is the same thing, but there are other ways to make money with energy storage as well.
Still seems extreme. IF my math is right, they would need to buy and sell 10MWh every day at a 27c/KWh markup. Given they they deliver at ~2.2 MW, This means that they would have to hit this markup for a 4 hour duration, every day.
They are likely operating on the wholesale markets, which are market priced. For the western grid there is a significantly wider price range of prices. On peak days in the summer, prices can go up above $1,000/mwh in the late afternoon for several days. During the late fall/early spring, there are negative prices in the late morning (like $20-$50/mwh) due to extremely high solar production and low demand, so utilities are literally paying you to use electricity. It's not inconceivable to get to $1 million a year on 1 mwh of storage.
Im familiar with energy markets. Im also familiar with the fact that any serious seller or buyer of energy locks in yearly pricing contracts and is unaffected by these swings. Any serious datacenter or industrial buyer is not relying on spot pricing. These energy markets also dont exist in every state.
If you are familiar with energy markets then by all means tell us the percentage breakdown of electricity consumed that is covered by long term contracts vs the spot market.
A lot of people look at these and think "that doesn't seem like it'd be remotely worth it for something that size" but it's really hard to explain just how badly California has painted itself into a corner on distant generation, huge variance between excess renewable capacity and peak load, and transmission congestion. The numbers don't make sense to people.
Pretty much all the solar plants we're putting in now have combined battery storage systems either for voltage support or "peaker" sales opportunities. In some places (like literal islands) it's about capacity smoothing or resilience, but the driving force behind all the investment is the US western interconnect with arbitrage opportunism starting to make real money and looking to make much, much more over the next decade.
If government-sachs is betting on this, they've probably got an even more pessimistic take on the CAISO market than I do.
Just read the constant stream of news about it? They keep shutting down power plants in the name of the environment, but just shift the generation outside of the state. It's a numbers game that's meaningless as long as they still consume power, but it lets them virtue signal all over the place to people who don't pay attention to details - which sadly is most of us. How many times when we are give stats do we really wonder about the context around them?
Buy low and sell high. They can find surplus power and buy it cheap, then wait until there are unmet demands and sell high.
These crazy things called computers make creating and automating markets like that pretty easy :)
It's win win - the people with surplus power can at least get some money for energy that would otherwise likely go to waste (large base load power plants can't ramp up and down on a dime) and on the flip side if you have an energy provider that only occasionally needs capacity in excess of their inherent generation even though the immediate cost is higher for spot power, it can still be far cheaper in the long term than building more base load generation (often fossil fuel because renewable still isn't a viable replacement for base loads). And running base load generation under capacity is wasteful for emissions and overall efficiency.
Once we start to crack the whole energy storage thing renewables will be A LOT more valuable since we will be able to start to use them for base load. Storage allows you to create reliable energy delivery that's predictable - that's essential if we ever want to eject fossil fuels from the grid. Or we could stop being childish about nuclear power - frankly I think we can solve the storage problem long before we can convince people to be rational about nuclear :p
It probably seems crazy for the uninitiated, but there are a lot of efficiencies in markets that occur naturally over time. You see distortions in the market from CA's stupid and politically motivated choices - what seems crazy to you is the market adapting to the model that CA is forcing. Is it nuts? Yup. Is it necessary? Nope - these wounds are entirely self inflicted. Pretending the world is different than it actually is doesn't solve anything and the people of CA are paying a hell of a lot more for electricity because they are trying to live in a pipe dream for where we are today.
There are times where the rooftop solar and base load generation for a utility is greater than the total electricity demand. Demand and supply for the grid have to be balanced, or else you will end up tripping plants and/or damaging equipment. Since they can't "turn off" rooftop and most grid scale solar generation, and they can't really turn off and on their base load plants throughout the day, their best option is to try to sell the excess electricity on the wholesale market. The problem is that the other utilities are in the same situation, and they need to offload electricity. Since no one wants the electricity, wholesale prices will actually go negative. Basically a utility will pay another utility to turn off a base load plant and take the excess electricity from them.
This is why grid scale energy storage is such a hyped technology - if you can store that energy when supply is way too high and dispatch it when renewable generation is low (no wind/solar), you can maintain high renewable percentage in the generation mix. Without it, you can only really go up to a certain percentage of renewables.
IF 10MWh is their daily cycle, they are selling 3,650,000 kWh/year.
To hit $1M per year, they would need to be selling ~27c/KWh above their buying price.
I get that you can have a big spread if you are being paid to take power, and paid again to sell it.
I think that’s it basically. New England consumers pay ~$.22/kWh. We’re going to have offshore wind energy in the next decade that might conceivably have surplus power quite a lot. It’s not beyond the realm of possibility that these plants could have a deal with the power plants to take extra power for free so long as they have guarantees on filling the expected gaps or meeting expected spikes in usage. Everyone wins.
In the 80s my grandfather used to do this for the former Soviet Union. Long story short they were pressuring a salt mine at night for energy storage and somebody failed to report a water leak during the day. They tried to depressurize the mine but it ended up blowing up anyway killing a couple people in The process. This shit can be really dangerous if done incorrectly.
Lots of water in a reservoir is not particularly safe in itself. For example, in December 2000 at the Grande Dixence a high-pressure pipeline from the dam burst, causing a landslide that wiped out a small hamlet and killed three people. It's also not hard to find reports of massive amounts of casualties and/or property damage from dams that just outright fail.
Yeah a large pressure vessel is basically a bomb. No matter how many layers of protection you add on the technology always wants to go too a rapid critical failure. Using statistics and layers of protection you can always show it to be safe to handle anything but when you get to such low probability your models be always be off and variables that you think are independent are actually linked (bad maintenance practices being one)
Water reservoirs for energy generation/storage have gone through accidents killing thousands. I suggest looking up Vajont on Wikipedia.
The project mentioned in the article seems particularly safe to me as they seem to run it with constant pressure, defined by the hydrostatic head of their deeply dug cavities. They don't really have a pressure vessel, they have a flooded cavern where they create a bubble by pushing in air. If you pop off a seal from the pipes connecting compressors/turbines to the bubble could still hurt yourself a lot shooting parts through the room, but that should be all.
The cavity they build is 2000 feet deep, which equates to the pressure of a CO2 cartridge that you'd use for e.g. carbonating a beverage. Not coincidentally at all I think, they either aim for the deepest cavity were hydrostatic pressure isn't enough to liquefy parts of the air, or for the least deep dig that gives them liquefication, where the air "boils off" as they open the valves.
Pumped storage is a bit different than an ordinary reservoir with a dam, though. You have more opportunity to build it in a place where it's less likely to cause harm is something goes wrong. It has been used pretty effectively on both sides of the border near Niagara Falls for 60+ years.
Yeah I realized that pretty much right after writing it, that it's biased from having gone through many iterations of dangers, and by now we know how to do it safer than less well used methods. So we can't say it's intrinsically safe only relatively from experience of use.
The Lake Peigneur Drilling Accident is a tale of water getting into a salt mine from the lake above, due to drilling for oil in the wrong place. As the water dissolved the salt, the hole grew bigger and bigger, exponentially. The lake emptied into the salt mine, turning it into brine.
So I'm picturing water leaking into a salt mine full of pressurized air. Naively it makes a hole, and a hole is just a leak. But if the water starts dissolving the salt in a process that runs away, then it is more like popping a balloon, but on a grand scale.
It's probably some kind of hedge strategy for energy crises like the recent Texas disaster (which appears to have been very profitable for GS [1]). Having this capacity around when other sources go down means they'll be able to provide power in similar situations and so reap massive profits. Climate chaos == $$$ I guess.
> Bloomberg March 5, 2021
> Goldman Sachs Group Inc. could gain more than $200 million from the physical sale of power and natural gas and from financial hedges after spot prices surged across much of the U.S., according to people with knowledge of the matter. Morgan Stanley’s gains could come in under $200 million, according to a person with familiar with the matter, and Bank of America Corp. stands to rake in profits as well...
> The historic cold that battered the central U.S. last month led to sweeping blackouts as ice formed on wind turbines and pipelines froze, forcing oil and gas wells to shut. As traders and power suppliers struggled to find fuel to meet obligations, prices skyrocketed. In Oklahoma, gas traded at more than 300 times normal levels, while electricity in Texas surged to $9,000 per megawatt-hour.
> Having this capacity around when other sources go down means they'll be able to provide power in similar situations and so reap massive profits. Climate chaos == $$$ I guess.
I understand that people don't like when others profit from a crisis, but this is also how we solve these problems. Having more generation capacity than we otherwise would have is a good thing, even if Goldman make money on the back of it.
I'm not arguing there isn't more to be done, but when people say "greed is good" this is what they mean.
This is where capitalism goes off the rails. Instead of investing $250m into making the power grid more secure and reliable, they choose to invest in profiting off disaster.
providing instant-on, scalable energy capacity to the grid is both potentially profiting off disaster and investing 250m into making the grid more reliable and secure.
You are sorely mistaken, this sort of battery is exactly what makes the grid more reliable and secure. Especially on grids like Texas, which have massive amounts of renewables.
Batteries are the Swiss Army knife of the grid, they can fix all sorts of problems, from inadequate transmission capacity, to frequency regulations, to peaking needs.
As others said, energy storage technology is going to be the only thing that makes renewable energy more than a curiosity. Renewable energy is neither reliable nor predictable which is why it can not replace base load requirements.
However, if we had sufficient energy storage capacity, they we could indeed fully transition to renewable energy once and for all!
I would like more detail on the "Thermal management system" and how long it could store the heat it captures.
One of the benefits they touting is "Long duration energy storage" I would think the limiting factor would be the ability of the thermal management system to retain the energy it captured to reheat the compressed air. Am I thinking about this correctly?
Air pressure is strongly correlated to temperature. Cooling the air after compression reduces pumping effort during storage, reheating it increases turbine head pressure during generation.
In other words: gas compression storage suffers from temperature losses. The compressed gas is hot, the heat dissipates from storage and that energy won't be coming back.
But if you extract that heat during compression you can put in a separate storage, one that is much easier to insulate than the compression tanks, and "mix it back in" during recompression, avoiding a large part of those losses.
> In other words: gas compression storage suffers from temperature losses.
Yes, and you can also compress air further when it's cooled (this is why there is an intercooler on turbocharged cars, as an example), this means your density per volume of storage is higher at a given pressure.
The reality though is that this is likely less efficient than many other storage mechanisms. Additionally, this may require some sort of additional energy input for reheating if the heat storage is not capable of holding long enough to fully reheat the air on release to get the highest turbine efficiency.
Warm air takes up more space. If you cool it before pumping it into the ground you will not waste time/energy.
If you pump warm air down it will lose heat into the ground and shrink and you would lose capacity - pumping that last x% the tanks will be fuller until they cool down.
You warm up the air on the way out to expand it and you get more air to spin the turbine. More bang for your buck.
> Warm air takes up more space. If you cool it before pumping it into the ground you will not waste time/energy.
The real masterstroke here might then be to put this system in an area with large diurnal temp changes like the desert, then charge this system with cool night air, and then reheat it and generate electricity during the day with warm daytime air. Heat pumps could be used to nudge the temp on either end into it's optimal range.
It then becomes a solar thermal hybrid compressed air energy storage.
This could pair well with renewables that are more available at night like onshore wind.
Many years ago I was doing shrooms in the Nevada desert -- and the epiphany I had was that the desert, and the caves all around and throughout the deserts served as "the lungs of the earth" -- they would heat and cool and would suck air in and out based on this...
I was 17 at the time, and I have been into some of the most incredible caves - the best in Ganung Mulu National Park in Borneo Malaysia...
As the rains flowed out and carried the guano from 5 million bats into the forest to fertilize it...
And then I realized it wasnt just the desert - it was the caves...
Caves (giant ones) are really important for planet health.
To the best of my knowledge that thinking is spot on.
A possible component that might be missing (in the thinking and/or in the proposed implementation): the stored heat could also be utilised separately if needed, so if you have an intermittent heat consumer and an intermittent electricity consumer you could consume the heat first, then leave the remaining compression energy (what you could recover without reheating) "forever". Bonus points if you also happen to have a coolant consumer to benefit from the temperature delta caused heat loss or premature heat consumption.
After seeing videos of lava pouring into the ocean I have fantasized about a power generation system:
Artificial geo-thermal power gen:
Dig a deep enough hole but near the ocean, and let ocean water pour into the hole that gets close enough to magma such that the magma creates a steam blast back out a tube with a bunch of turbines to spin.
> One of the benefits they touting is "Long duration energy storage"
According to their marketing video [1] "Long duration" is relative to current lithium ion battery-based storage. So their system can store energy up to 24 hours vs a few hours for batteries.
For even longer term storage (weeks, months, seasons), some time of chemical storage will be needed. Currently, both hydrogen electrolysis and ammonia synthesis [2] are being explored for that.
But Goldman Sachs can blow their money however they wish. Although no doubt governments will also throw bad money into this, but I guess if people want their government to fake their lives, so be it. It seems that's living in The Jetsons future HN idolises.
Air is kind of a shitty working fluid. I always kind of dismiss compressed air storage because of that.
I saw a video recently that pumped water into tanks and used used the air as a spring. Just dip a pipe down and use the air to move the water. Extracting energy from a hyrdo generator.
It is pumped hydro, but you don't have the same mass of water because of the dramatically different pressures involved. Smaller water mass is the advantage to this, but the problem of managing heat is the downside that pumped storage doesn't face.
This general technique is known as "liquid piston".
Thanks for the search term.
I am not a huge fan of the "advanced polymer" wank of that video but liquid piston seems very practical compared most of the "air powered car" nonsense compressed air systems that show up.
Grid storage is going to be big business in the future, on the order of size of storage for electrical vehicles. (And these will certainly not be mutually exclusive markets! Vehicle to grid tech will become widespread, as is already seen in the new F150 Lightning truck). Lithium ion will dominate for the foreseeable future, as the industry has scaled to massive sizes and already, and has the advantage of being currently unstoppable in the EV space.
Batteries with a design that can decouple the energy from the power ratings, like this one, will be able to address parts of the market that lithium ion cannot. And if the cost per MWh of additional energy is cheap, and round trip efficiency stays above 50% or so, that sort of battery will have a huge edge in a part of the market that currently has no clear winners.
There are many competitors in the non-lithium ion storage space, but one of the top contenders to watch is Form energy, which has a rust-based battery, and is rumored to have a cost as low as $20/MWh, about a tenth of that of lithium ion.
> one of the top contenders to watch is Form energy, which has a rust-based battery.
Form is still in the cell prototyping stage, as best I can tell - maybe not even that. There's zero information on their website about where they are in the development process or really anything substantial about their design.
Competition in the market is certainly a good thing, but Form needs to do more than just have a shiny website, a screengrab of a zoom employee meeting, and a blog with 'industry insight' posts (because they have nothing to show for tech/product.)
Agreed that Form has lots of hype, but that's one thing that can be needed in addition to working tech. Utility decision makers are not the best at adding new tech to the grid or dealing with innovation. Having some big industry names and the support of the business press that the utility execs and shareholders read is it's own form of currency when dealing with such archaic businesses.
Form has no working tech, as evidenced by the total absence of any mention of it. No specs, no pictures, no test installations, no whitepapers, nothing.
I still believe that's why the U.S. invaded anyway. We didn't care about overtaking a country for some silly resistance leader. You do it for big money to bilk - like Iraq and oil.
But we left without taking any lithium. At some point second and third order hypotheticals are just conspiracy theories. There is no evidence we invaded Afghanistan to get lithium, and at the time (2001), we were not worried about lithium shortages or grid storage.
Like others I don't think that that's why the US invaded, but I do think it had something to do with the enormous shit-fit thrown by the DC foreign policy / national security / defense commentariat when we pulled out of Afghanistan last summer.
Lithium Ion is not sustainable for the long term - we have neither the materials nor the manufacturing to not only keep up what would be required for full scale car and grid uses, but don't forget Lithium Ion batteries have a finite lifespan and need to be replaced. The more you put into service, the more you have to manufacture beyond just the batteries needed for new requirements.
I'm not sure that your predictions will hold here. More lithium is discovered as demand grows, and there have been huge additions to known reserves in just the past few years. Looking at current numbers and saying "that's it" is clearly wrong, and given its overall abundance and lack of demand until now, it's a really strong prediction to say that we won't have enough for at least 500TWh of storage, if not more.
Manufacturing capacity is expected to increase 10x every five years, with roughly 20-30TWh/year production in 2031. I can't think of any fundamental constraints there, could you specify why that can't increase?
Lithium recycling is being planned by nearly all manufacturers and many countries will mandate it. If lithium supplies are short, recycling will be highly profitable. If lithium is super abundant, recycling may be more expensive than recycling, and a program like what we currently use for lead acid batteries might be needed for a circular economy. But the fundamental point is that end of life for the battery does not mean that the lithium is gone, it's not a fuel.
How did you collect this odd set of concerns? Did you think of them or did you find them in the media somewhere?
It's all a question of economics. I think technologies like the one in this article, or the one I think holds the best long term promise - super capacitors - are far more likely to displace lithium ion batteries before all that infrastructure you describe scales out. Recycling a battery pack out of a car like a Tesla is far different than recycling a traditional led acid battery from a car. Recycling the quantity of batteries required to support the grid at scale is even more of a non-trivial problem. And if recycling isn't economically viable because lithium is so abundant what do you do with the spent batteries? Bury them?
Especially for electric cars - without something like a supercapacitor or hydrogen that can charge quickly and doesn't have massive battery pack replacement costs built in to the total cost of ownership equation, electric cars are not going to become mainstream; they will remain fringe oddities.
I don't think Lithium is going away tomorrow - but I think it's crazy to bank on it for all our future needs or pitch it for grid storage. If it was so viable for grid storage then where are the really large deployments at scale? As you point out its mature tech. Someone would have scaled up production and done it already if it was such a no brainer. If Elon thought he could make more money at it than cars or space do you not think he would already be there focusing on it vs. those other ventures? Heck at one point Elon was thinking of doing his own candy but didn't since he didn't find anything really revolutionary enough to separate his potential offering from what was already out there. So it's not like he has a super narrow focus only on what he's already working on, and he already has a ton of in-house knowledge about lithium ion batteries.
That a company with as high knowledge of lithium battery tech like Tesla is only tangentially focused on grid power solutions instead of heavily diving in is, I think, one of the larger tells out there. And do you think Tesla would still be as successful if it didn't have substantial tax incentives? That's a distortion that's often overlooked when talking about overall economic viability.
There is far more than just raw resource availability or basic manufacturing capabilities at play here - and grid scale requirements just amplify those issues. I dunno why so many people are so eager to hand wave the limited lifetime of chemical batteries but it's a significant issue; any tech that doesn't have 100% replacement over a short fixed lifetime is going to beat the pants off of chemical batteries over the long haul. It isn't even remotely close. Utilities think in 50 year lifetimes, not 5. These aren't solutions for cars; this is base infrastructure that's COSTLY. There is probably some maintenance with these compressed air solutions, but I'm pretty confident it's no where near that of being forced to replacing the most expensive part of your entire storage solution every X years.
Just look at the value of a used electric cars vs. new. As people are learning about battery pack replacement costs or especially with Tesla, limited options on repair/partial replacement and probably loosing access to supercharging(one of the biggest reasons to pick Tesla right now), used prices on electric cars have steadily declined (and that's being a bit polite). When you have someone blowing up a used Tesla because they feel it's not economically viable to replace the battery pack, that' an issue that shouldn't just be hand waved away Melatonic↗
I have been saying for years that we should have a windmill system you could place on top of a building or home that powers a larger, highspeed flywheel buried underground below the house. Ideally with the flywheel in vacuum and balanced by magnets for reduced friction. This ensures no loss converting energy types (mechanical to mechanical) and it can be used later for electricity or other energy in small, large bursts (sort of like a capacitor). You would still want batteries for energy storage but this would drastically increase the lifespan of those batteries by reducing stress on their chemistry. Batteries really do not like to discharge in short, high intensity bursts. There are flywheel based UPS systems that work sort of in a similar principle and they have much longer maintenance intervals vs a battery type UPS>
I think both battery and solar tech has advanced to the point that solar plus batteries undercut a lot of grid supplied energy in costs.
Or at least it would, if the overhead for current solar installers wasn't so high. Retail prices for equipment are incredibly low, but the boom-and-bust cycle caused by uncertain regulatory terrain ends up requiring successful biz to have massive marketing costs, which results in really high prices overall.
I'm not sure how that would help? If you had a flywheel and you didn't need the energy, what do you do with it? At least without a flywheel, you can easily stop the turbine.
Also, any flywheel that would add significant difference would probably weigh hundreds of tonnes, which would make construction massively more expensive and difficult.
If you don't need the energy you just let the flywheel spin freely. It's a mechanical battery. I agree with your second point though- it would add considerable mass to the hub assembly of the wind turbine and there is no clear way to transmit the mechanical energy to ground level.
i agree, wind turbines do rotate but not at high speeds, disintegration of one doesn’t lead to catastrophic outcomes. Flywheels on the other hand are meant to rotate at high speeds and hold lots of energy, so destruction of the spindle would lead to some pretty big bad results
Yes, except with several orders of magnitude more energy and rotating mass.
Wind turbine blades are engineered for minimum mass and inertia, are manufactured primarily from fiberglass and/or carbon fiber, are hollow, and the largest mass is in the center.
In contrast, flywheels are engineered for the highest practical inertia, are manufactured from the highest density material that works, and concentrate that mass as far out as possible.
When a wind blade fails catastrophically, it makes a mess of splinters right around the tower, as shown in [0] and [1].
In contrast, just a small automotive flywheel explosion, contained in a legally mandated scattershield, is almost as spectacular [2], [3]. Now, magnify that from a flywheel just designed to smooth the power from a 375kW (500HP) engine to the scale of a flywheel to STORE the energy of a megawatt-scale wind turbine.
So, no, the danger of a megawatt-scale energy storage flywheel is NOT like the danger of a "giant rotating wind turbine".
Ha! Interesting, I had noticed the horses seemed off. In the comments it looks like the author was playing with CGI and modeled it on the Dutch failure video. I'd obviously just posted results of a quick search for short vids.
If you're thinking of a direct mechanical linkage, you wouldn't want to put it up on the tower because the mass to effectively store megawatt-scale power is way more than you'd want to support up high. Also, since the wind blade usually swivels to the wind, you'd want to avoid the rotational inertia. So, you'd need a mechanical linkage to transmit the power to the ground, maybe installing it under the tower base.
You would not want to use a direct mechanical attachment, i.e., resembling a combustion engine - transmission flywheel, because this would impair the ability of the wind turbine to start. Generally, turbines are designed for minimum inertia to easily start in low-wind conditions. A direct connection would impede that.
Now, we're adding a clutch-sort of mechanism, and that has its own additional complexity, weight, and energy.
Moreover, considering that we're trying to store megawatt-scale energies, we are at a large mass spinning very fast, and probably spun up with an electric motor.
So, it would seem the best way to do that would be to make a flywheel farm, with the flywheels below ground to contain failures. At this point, why locate it in the probably inconvenient location where the wind turbines are located, and instead put it somewhere more convenient, such as nearer to the consumption areas?
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[ 0.21 ms ] story [ 317 ms ] threadWould be great to see this technology reach maturity!
In 2018, the tech couldn't compete against lithium ion, and the price of lithium ion continues to fall 10-20% per year.
Compressed air and that concrete-block-stacking nonsense that keeps getting press are just magnets for uneducated investors.
> Compared to traditional batteries, CAES systems can store energy for longer periods of time and have less upkeep.
Sometimes the cost per MW/hr or equivalent is not the only metric worth thinking about.
https://en.wikipedia.org/wiki/Compressed-air_energy_storage
Even if you use natural gas as a reheating element, the compressed air stores a significant amount of energy and is doing the majority of the work.
Efficiency / cost
I am worried that the cost is the driving factor here...
Goldman wouldn't be making that kind of an investment if they didn't have a handle on both parts of the equation. Indeed efficiency (dealing with losses from seepage) have been the nut that hasn't been cracked with compressed air storage; these guys seem to have an economical (efficient) way to deal with that problem. If true, then they really are worthy of Goldman's investment.
Air tools can also be lighter and no worries abt damaging the cord or carrying the battery.
Many good air tools can also have a better feel, especially if you can control the air flow trigger.
(I don't have a bias either way, use both in my shop, but just wanted to point out that both have advantages)
My complaint, really, is just how selfish it is to go out of your way to use a dirty energy source as a workaround for limits in your personal belief system.
And yes, using diesel to power your compressor on a regular (non-emergency) is more than a bit wasteful.
I totally get their insistence on staying off-grid, and it is good to read that they seem to be positive towards solar, so we can hope that takes over soon! From the bits I've read about their ethos, it certainly should have the advantage of further reduced dependency on outside systems, in this case, a one-off purchase of solar panels & kit will eliminate ongoing dependence on the entire fossil fuel supply chain.
I don't know if it's still there, but there used to be a fancy restaurant in the Eastlake part of Seattle that had started out that way, and still had the old Art Deco-ish drive shaft running around the ceiling. It was a neat touch point when I saw it and remembered my dad's description from years before.
Later the waterwheel was replaced by an electric motor or a fuel powered engine - but still built around just one source of power, with elaborate setups to drive different tools. With the added benefits you could build factories and workshops outside main water sources.
The Edison museum in Orange NJ also has such a preserved shop setup but electric driven by one or two big motors on an elevated platform.
After watching it, I now understand that they aren't flooding the entire borehole, but rather are building a smaller high-pressure chamber at the bottom. The chamber is connected to pipes to a surface reservoir. When air is pumped into the chamber, it displaces water up toward the surface. When generating, the water flows back into the subsurface chambers, forcing out the high pressured air.
[1] https://www.youtube.com/watch?v=GicQwXbNnv0
all the temperature management here looks to just be counteracting the temperature changes that naturally occur when you compress or expand a gas. i imagine if you compressed it and then pumped hot air into water-filled caverns you'd get some negative effects of thermal shock.
What's the element I'm missing as to why they didn't?
Also, digging (or rather drilling) in bedrock is hard without motorized equipment and good steel.
Also, supplying fresh air down there is a problem.
Also, preventing the mine from flooding is usually a huge problem.
Mining is hard and a lot of people lost their lives doing that. That said, if your only intent is to get a bit warmer, you may basically try a good cave. Caves tend to have temperatures above freezing for the whole year.
https://en.wikipedia.org/wiki/Panthera_spelaea
IDK if these lions hibernated, but their bones are definitely found in caves all over Europe. Often with human remains or artifacts nearby.
https://en.m.wikipedia.org/wiki/Woodingdean_Water_Well
Not sure about the rate per-mile, but literally it's that hot, yes, but not even 15 miles. Just down 5-7km under the oceans, for example at the Mohorovičić discontinuity the temp ranges from 392 to 752F.
In the Nat Geo article they quote a mine in South Africa reaching up to 55C (131 F) at the bottom and the mine is 4km deep. At a rate 3 degrees Celsius per 100m it should be 120 degrees Celsius over ambient. Which obviously does not add up.
https://en.m.wikipedia.org/wiki/Kurobe_Seny%C5%8D_Railway
Cooled down to 40C since the 60s.
> The heat is transferred from the interior towards the surface mostly by conduction, and this conductive heat flow makes temperature rise with increasing depth in the crust on average 25-30°C/km
Very incorrect.
Everyone who might have shared the same misapprehension learned something and the parent wasn’t being an asshole.
Doesn’t that add to the discussion?
(http://www.welshcoalmines.co.uk/forum/read.php?14,46717,4671...)
"...but other parts of the mine was very cold you made sure you had plenty to ware it depended where you worked"
(https://www.quora.com/Are-coal-mines-cold/answer/Keith-Scott...)
"Underground mines maintain a constant temperature, around 55 degrees Fahrenheit."
(https://www.quora.com/Are-coal-mines-cold/answer/Tom-Inghram)
«The temperature on average is in the 50s, but you still sweat an enormous amount when you start laboring.“ - Alan Bates, working in the coal mines of Letcher County, Kentucky.»
(https://www.quora.com/Whats-it-like-working-in-a-coal-mine/a...)
Yes, a 4000m gold mine is hot. I doubt that's where they're storing their compressed air.
Why was this not built before? I have no idea. Maybe robots are essential, we didn't have deep enough mines that were abandoned, energy was cheaper, no push for no emissions, it's not economical, other risks.
https://en.m.wikipedia.org/wiki/Kyshtym_disaster
Having nuclear stuff underground requires extremely precise geological surveys, so that the stuff does not wind up in aquifer.
- After a few dozen years, the concrete is expected to breach,
- Radioactive atoms mix up with soil and dissipate both upwards and downwards, mostly thanks to water,
- After 400 years and for thousands of years, they reach the surface, where they should be diluted enough to not be dangerous,
So I guess having badly contained radioactive containers would be much worse.
One thing to remember is that pressure underground is extremely high (stone weighs a lot more than water, and light rock tends to “float” onto denser rock). If a melted reactor were squeezed, it would spread materials into the soil much quicker.
Also nuclear power plants obviously generate an absolutely massive amount of heat that needs to be dissipated, a task that would be difficult and expensive underground.
A report from 1961: https://www.ideals.illinois.edu/bitstream/handle/2142/42910/...
Maybe they're referring to Goldman Sachs Capital partners which has 39.9B[0] under management which means this is 0.62% of their portfolio. In a totally chalk and cheese comparison that would be having 200k in your 401k and taking a $1,250 position in a stock, which isn't nothing but is a pretty small bet, I agree. Curious though if I'm guessing the part of GS correctly; I have no idea how they're structured and just spent like three minutes searching.
[0] https://en.wikipedia.org/wiki/Goldman_Sachs_Capital_Partners
Having had GS invest in companies in the energy tech space in the past and having not particularly great success - I wouldn't think this is a strong signal. More that the financial heavyweights think there is action and they want to get in.
Its small money on a broad industry bet thats all in an economy with very few quality investments available. Don't read too much into it.
Seriously?
Some citations from an article: “Bottled wind could be as constant as coal.” Wired Magazine. Retrieved 7/15/2010, 2010, from http://www.wired.com/wiredscience/2010/03/compressedair-plan... 59
Cavallo, A. (2005). Controllable and affordable utility-scale electricity from intermittent wind resources and compressed air energy storage (CAES). Science Direct.
Well, yeah, this is in the opening of the article:
> It updates a long-standing technology that never took off for electrical storage.
There is/was plant operational since 1970s in Germany[1], which looks similar to the Wired article, but different from some other solutions posted in comments. Missing some parts perhaps to be viable.
1. PDF: http://www.fze.uni-saarland.de/AKE_Archiv/AKE2003H/AKE2003H_...
The article seem to mostly describe this as a technology project to test the technology at scale, but they do also mention profits. Is the basic premise of buy low sell high, exclusively on renewables, enough to offset the cost from energy conversion, building, staff and other costs, and if so, by what degree compared to other method to produce energy? When is it estimated to have paid its initial investment?
Current solar and wind renewables are NOT predictable nor reliable for sustained power generation. With Coal, Natural Gas, Nuclear and Hydro you can generate power on demand, no matter what the environment is doing. Well, Hydro in the west is getting dicey with the drought - but even that is far more stable than wind/sun which can vary wildly week to week, day to day or even hour to hour.
That's why technology like this is so exciting. If you can look at the average production of a renewable over a month, then within a year the peak month, then look at the worst months, then have enough storage to cover a percentage of a peak month based off the hedge of the worst month then you are getting to a point where a solar farm isn't just an opportunistic source of power based on how much the sun is shining, but a reliable energy source that can be counted on whether the sun is shining or not.
Same for wind farms.
Energy storage is crucial if we seriously want to transition to renewables and hence the investment from Goldman Sachs.
If this company is even remotely successful in actually delivering then $250M is a pittance to what they will receive back in the long term.
There are also a lot of unused/abandoned underground structures - from various wells that are now dry of the resource they were originally drilled for to mines that are no longer productive. The problem has been sealing them from seepage so you don't loose your stored air - this article was light on details but that seems to be this companies claim to fame. They seem to have found economical ways to deal with those issues - enough to convince the boffins at Goldman Sachs they are worthy of investment. I guarantee you Goldman is not just tossing out money willy-nilley without performing some significant due diligence!
When people discuss green hydro as a storage solution the numbers so far, from what I have managed to interpret, is around 3-5 times that off nuclear for the same amount of energy delivered. It is still technically possible to make a profit given enough subsidies and time, and it get much more economically if the hydrogen can be used directly in the production chain like steel and fertilizer. Right now there are a steel foundry in Sweden testing the technology and economics doing that, through I don't know how much subsidies and tax reductions were involved.
Which all means the question about economics remains. There are many alternatives to fossil fuels but the primary question everyone debates is the issue of price. Without a price per watt/h or a time frame for when the investment get repaid its impossible to separate the practical from impractical, and the subsidy question is very relevant when discussing this on a national level.
https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
there is no rule that water+ turbines is more efficiency than Solid mass + alternators.
If you can't build it where you need it, then efficiency doesn't really matter now, does it?
https://www.lowtechmagazine.com/2018/05/history-and-future-o...
0. https://news.ycombinator.com/item?id=29905288
reminiscent of The Day Today https://www.youtube.com/watch?v=eTGE9153VFE
They claim 1m in revenue from their existing product which is: "1.75 megawatts (MW) of peak power output; a 2.2 MW charge rating; and 10+ megawatt-hours (MWh) of storage capacity"
How does that equal 1m in revenue? You have to pay to charge your air-battery during low-cost hours and then discharge it during high cost hours to make the difference in revenue.
The issue is, you can buy 2 megawatts of power 24/7 at average datacenter energy pricing (~5c/kwh) for $2400/day or 876k/year. Who is paying more than that for less energy and only at certain hours?
Is there some energy company somewhere that sells power during the day at like 50c/kwh and 1c/kwh at night???
The Hydrostor plant is in Ontario. Here's an archive of hourly spot-market electricity prices there (in dollars per MWh): http://reports.ieso.ca/public/PriceHOEPPredispOR/. So far in 2022, prices have been as low as $0.00/MWh (during a few hours overnight on Jan 5) and as high as $230.87/MWh (during the morning of Jan 11). In 2021, hourly average prices even exceeded $1000/MWh ($1/kWh) twice, on March 28 and October 10.
Wheres the rest? And what about if you cant nostradamus predict the best times to buy and sell?
https://smartgrid.ieee.org/bulletins/january-2016/energy-sto....
Sometimes utilities only need a few minutes of power to cover small gaps while ramping up/down powerplants, or if a cloud passes over a solar generation facility. Since these volumes are very small but critical, the effective price per MWH is extremely high.
When Tesla did their grid scale battery installation in Australia, this is how they made their money. Not via energy arbitrage, but with selling frequency response services. I have no idea if this is the same thing, but there are other ways to make money with energy storage as well.
Take a look at the price maps and historical pricing data if you are curious https://www.caiso.com/todaysoutlook/Pages/prices.html
Pretty much all the solar plants we're putting in now have combined battery storage systems either for voltage support or "peaker" sales opportunities. In some places (like literal islands) it's about capacity smoothing or resilience, but the driving force behind all the investment is the US western interconnect with arbitrage opportunism starting to make real money and looking to make much, much more over the next decade.
If government-sachs is betting on this, they've probably got an even more pessimistic take on the CAISO market than I do.
source needed if you're making such a bold statement
These crazy things called computers make creating and automating markets like that pretty easy :)
It's win win - the people with surplus power can at least get some money for energy that would otherwise likely go to waste (large base load power plants can't ramp up and down on a dime) and on the flip side if you have an energy provider that only occasionally needs capacity in excess of their inherent generation even though the immediate cost is higher for spot power, it can still be far cheaper in the long term than building more base load generation (often fossil fuel because renewable still isn't a viable replacement for base loads). And running base load generation under capacity is wasteful for emissions and overall efficiency.
Once we start to crack the whole energy storage thing renewables will be A LOT more valuable since we will be able to start to use them for base load. Storage allows you to create reliable energy delivery that's predictable - that's essential if we ever want to eject fossil fuels from the grid. Or we could stop being childish about nuclear power - frankly I think we can solve the storage problem long before we can convince people to be rational about nuclear :p
It probably seems crazy for the uninitiated, but there are a lot of efficiencies in markets that occur naturally over time. You see distortions in the market from CA's stupid and politically motivated choices - what seems crazy to you is the market adapting to the model that CA is forcing. Is it nuts? Yup. Is it necessary? Nope - these wounds are entirely self inflicted. Pretending the world is different than it actually is doesn't solve anything and the people of CA are paying a hell of a lot more for electricity because they are trying to live in a pipe dream for where we are today.
This is why grid scale energy storage is such a hyped technology - if you can store that energy when supply is way too high and dispatch it when renewable generation is low (no wind/solar), you can maintain high renewable percentage in the generation mix. Without it, you can only really go up to a certain percentage of renewables.
IF 10MWh is their daily cycle, they are selling 3,650,000 kWh/year. To hit $1M per year, they would need to be selling ~27c/KWh above their buying price.
I get that you can have a big spread if you are being paid to take power, and paid again to sell it.
https://en.wikipedia.org/wiki/Johnstown_Flood
The project mentioned in the article seems particularly safe to me as they seem to run it with constant pressure, defined by the hydrostatic head of their deeply dug cavities. They don't really have a pressure vessel, they have a flooded cavern where they create a bubble by pushing in air. If you pop off a seal from the pipes connecting compressors/turbines to the bubble could still hurt yourself a lot shooting parts through the room, but that should be all.
The cavity they build is 2000 feet deep, which equates to the pressure of a CO2 cartridge that you'd use for e.g. carbonating a beverage. Not coincidentally at all I think, they either aim for the deepest cavity were hydrostatic pressure isn't enough to liquefy parts of the air, or for the least deep dig that gives them liquefication, where the air "boils off" as they open the valves.
It's not perfect, of course. Accidents still happen, for example: https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_... although fortunately nobody was killed.
https://en.wikipedia.org/wiki/Lake_Peigneur
So I'm picturing water leaking into a salt mine full of pressurized air. Naively it makes a hole, and a hole is just a leak. But if the water starts dissolving the salt in a process that runs away, then it is more like popping a balloon, but on a grand scale.
> Bloomberg March 5, 2021
> Goldman Sachs Group Inc. could gain more than $200 million from the physical sale of power and natural gas and from financial hedges after spot prices surged across much of the U.S., according to people with knowledge of the matter. Morgan Stanley’s gains could come in under $200 million, according to a person with familiar with the matter, and Bank of America Corp. stands to rake in profits as well...
> The historic cold that battered the central U.S. last month led to sweeping blackouts as ice formed on wind turbines and pipelines froze, forcing oil and gas wells to shut. As traders and power suppliers struggled to find fuel to meet obligations, prices skyrocketed. In Oklahoma, gas traded at more than 300 times normal levels, while electricity in Texas surged to $9,000 per megawatt-hour.
Full article: [1] https://www.investorvillage.com/smbd.asp?mb=5028&mn=126049&p...
I understand that people don't like when others profit from a crisis, but this is also how we solve these problems. Having more generation capacity than we otherwise would have is a good thing, even if Goldman make money on the back of it.
I'm not arguing there isn't more to be done, but when people say "greed is good" this is what they mean.
Batteries are the Swiss Army knife of the grid, they can fix all sorts of problems, from inadequate transmission capacity, to frequency regulations, to peaking needs.
However, if we had sufficient energy storage capacity, they we could indeed fully transition to renewable energy once and for all!
One of the benefits they touting is "Long duration energy storage" I would think the limiting factor would be the ability of the thermal management system to retain the energy it captured to reheat the compressed air. Am I thinking about this correctly?
But if you extract that heat during compression you can put in a separate storage, one that is much easier to insulate than the compression tanks, and "mix it back in" during recompression, avoiding a large part of those losses.
Yes, and you can also compress air further when it's cooled (this is why there is an intercooler on turbocharged cars, as an example), this means your density per volume of storage is higher at a given pressure.
The reality though is that this is likely less efficient than many other storage mechanisms. Additionally, this may require some sort of additional energy input for reheating if the heat storage is not capable of holding long enough to fully reheat the air on release to get the highest turbine efficiency.
You warm up the air on the way out to expand it and you get more air to spin the turbine. More bang for your buck.
I believe is the thinking.
The real masterstroke here might then be to put this system in an area with large diurnal temp changes like the desert, then charge this system with cool night air, and then reheat it and generate electricity during the day with warm daytime air. Heat pumps could be used to nudge the temp on either end into it's optimal range.
It then becomes a solar thermal hybrid compressed air energy storage.
This could pair well with renewables that are more available at night like onshore wind.
I was 17 at the time, and I have been into some of the most incredible caves - the best in Ganung Mulu National Park in Borneo Malaysia...
As the rains flowed out and carried the guano from 5 million bats into the forest to fertilize it...
And then I realized it wasnt just the desert - it was the caves...
Caves (giant ones) are really important for planet health.
A possible component that might be missing (in the thinking and/or in the proposed implementation): the stored heat could also be utilised separately if needed, so if you have an intermittent heat consumer and an intermittent electricity consumer you could consume the heat first, then leave the remaining compression energy (what you could recover without reheating) "forever". Bonus points if you also happen to have a coolant consumer to benefit from the temperature delta caused heat loss or premature heat consumption.
Artificial geo-thermal power gen:
Dig a deep enough hole but near the ocean, and let ocean water pour into the hole that gets close enough to magma such that the magma creates a steam blast back out a tube with a bunch of turbines to spin.
CEO Nwabudike Morgan likes this (reference to Sid Meier's Alpha Centauri in case you were wondering)
According to their marketing video [1] "Long duration" is relative to current lithium ion battery-based storage. So their system can store energy up to 24 hours vs a few hours for batteries.
For even longer term storage (weeks, months, seasons), some time of chemical storage will be needed. Currently, both hydrogen electrolysis and ammonia synthesis [2] are being explored for that.
1. https://youtu.be/cOWjwwKSR78?t=136
2. https://www.youtube.com/watch?v=5Y_2Z_VwFNc
But Goldman Sachs can blow their money however they wish. Although no doubt governments will also throw bad money into this, but I guess if people want their government to fake their lives, so be it. It seems that's living in The Jetsons future HN idolises.
Why it is fake - "Why is adiabatic compressed air energy storage yet to become a viable energy storage option?" - https://www.cell.com/iscience/pdf/S2589-0042(21)00408-9.pdf
The Australian project has no go ahead -
Hydrostor seeks clarity over compressed air-energy storage facility in Broken Hill - https://www.abc.net.au/news/2022-01-12/hyrdostor-seeks-clari...
And yes as part of this fake world, Goldman Sachs has not put 250M into this company, it's in tranches. Fake worlds built on top of fake worlds.
I saw a video recently that pumped water into tanks and used used the air as a spring. Just dip a pipe down and use the air to move the water. Extracting energy from a hyrdo generator.
https://youtu.be/sBF5EnK9MPs
This general technique is known as "liquid piston".
Batteries with a design that can decouple the energy from the power ratings, like this one, will be able to address parts of the market that lithium ion cannot. And if the cost per MWh of additional energy is cheap, and round trip efficiency stays above 50% or so, that sort of battery will have a huge edge in a part of the market that currently has no clear winners.
There are many competitors in the non-lithium ion storage space, but one of the top contenders to watch is Form energy, which has a rust-based battery, and is rumored to have a cost as low as $20/MWh, about a tenth of that of lithium ion.
Form is still in the cell prototyping stage, as best I can tell - maybe not even that. There's zero information on their website about where they are in the development process or really anything substantial about their design.
ESS on the other hand has a design they've had out testing in the field for a couple years ( https://essinc.com/ess-inc-to-deliver-two-energy-warehouse-s... is one such location) and has been shipping actual product: https://www.businesswire.com/news/home/20211115006337/en/ESS... and they've been pretty open about their design, though some of their old whitepapers have been removed from the site.
Competition in the market is certainly a good thing, but Form needs to do more than just have a shiny website, a screengrab of a zoom employee meeting, and a blog with 'industry insight' posts (because they have nothing to show for tech/product.)
Form has no working tech, as evidenced by the total absence of any mention of it. No specs, no pictures, no test installations, no whitepapers, nothing.
it's already a big business
Manufacturing capacity is expected to increase 10x every five years, with roughly 20-30TWh/year production in 2031. I can't think of any fundamental constraints there, could you specify why that can't increase?
Lithium recycling is being planned by nearly all manufacturers and many countries will mandate it. If lithium supplies are short, recycling will be highly profitable. If lithium is super abundant, recycling may be more expensive than recycling, and a program like what we currently use for lead acid batteries might be needed for a circular economy. But the fundamental point is that end of life for the battery does not mean that the lithium is gone, it's not a fuel.
How did you collect this odd set of concerns? Did you think of them or did you find them in the media somewhere?
Especially for electric cars - without something like a supercapacitor or hydrogen that can charge quickly and doesn't have massive battery pack replacement costs built in to the total cost of ownership equation, electric cars are not going to become mainstream; they will remain fringe oddities.
FYI if you aren't aware of super capacitors there has been significant progress in bringing them to scale: https://undecidedmf.com/episodes/revisiting-the-supercapacit...
I don't think Lithium is going away tomorrow - but I think it's crazy to bank on it for all our future needs or pitch it for grid storage. If it was so viable for grid storage then where are the really large deployments at scale? As you point out its mature tech. Someone would have scaled up production and done it already if it was such a no brainer. If Elon thought he could make more money at it than cars or space do you not think he would already be there focusing on it vs. those other ventures? Heck at one point Elon was thinking of doing his own candy but didn't since he didn't find anything really revolutionary enough to separate his potential offering from what was already out there. So it's not like he has a super narrow focus only on what he's already working on, and he already has a ton of in-house knowledge about lithium ion batteries.
That a company with as high knowledge of lithium battery tech like Tesla is only tangentially focused on grid power solutions instead of heavily diving in is, I think, one of the larger tells out there. And do you think Tesla would still be as successful if it didn't have substantial tax incentives? That's a distortion that's often overlooked when talking about overall economic viability.
There is far more than just raw resource availability or basic manufacturing capabilities at play here - and grid scale requirements just amplify those issues. I dunno why so many people are so eager to hand wave the limited lifetime of chemical batteries but it's a significant issue; any tech that doesn't have 100% replacement over a short fixed lifetime is going to beat the pants off of chemical batteries over the long haul. It isn't even remotely close. Utilities think in 50 year lifetimes, not 5. These aren't solutions for cars; this is base infrastructure that's COSTLY. There is probably some maintenance with these compressed air solutions, but I'm pretty confident it's no where near that of being forced to replacing the most expensive part of your entire storage solution every X years.
Just look at the value of a used electric cars vs. new. As people are learning about battery pack replacement costs or especially with Tesla, limited options on repair/partial replacement and probably loosing access to supercharging(one of the biggest reasons to pick Tesla right now), used prices on electric cars have steadily declined (and that's being a bit polite). When you have someone blowing up a used Tesla because they feel it's not economically viable to replace the battery pack, that' an issue that shouldn't just be hand waved away Melatonic ↗ I have been saying for years that we should have a windmill system you could place on top of a building or home that powers a larger, highspeed flywheel buried underground below the house. Ideally with the flywheel in vacuum and balanced by magnets for reduced friction. This ensures no loss converting energy types (mechanical to mechanical) and it can be used later for electricity or other energy in small, large bursts (sort of like a capacitor). You would still want batteries for energy storage but this would drastically increase the lifespan of those batteries by reducing stress on their chemistry. Batteries really do not like to discharge in short, high intensity bursts. There are flywheel based UPS systems that work sort of in a similar principle and they have much longer maintenance intervals vs a battery type UPS> epistasis ↗ I think both battery and solar tech has advanced to the point that solar plus batteries undercut a lot of grid supplied energy in costs. [dead] WheatM ↗ mispell ↗ That's already a thing. Kodiak AK has one which coupled with wind turbines enabled the town to go to 99% renewable electricity. https://www.hitachienergy.com/us/en/references/grid-edge-sol... Melatonic ↗ Holy shit this is super cool!
Or at least it would, if the overhead for current solar installers wasn't so high. Retail prices for equipment are incredibly low, but the boom-and-bust cycle caused by uncertain regulatory terrain ends up requiring successful biz to have massive marketing costs, which results in really high prices overall.
Also, any flywheel that would add significant difference would probably weigh hundreds of tonnes, which would make construction massively more expensive and difficult.
"What if a 5MW flywheel broke it's spindle?"
Wind turbine blades are engineered for minimum mass and inertia, are manufactured primarily from fiberglass and/or carbon fiber, are hollow, and the largest mass is in the center.
In contrast, flywheels are engineered for the highest practical inertia, are manufactured from the highest density material that works, and concentrate that mass as far out as possible.
When a wind blade fails catastrophically, it makes a mess of splinters right around the tower, as shown in [0] and [1].
In contrast, just a small automotive flywheel explosion, contained in a legally mandated scattershield, is almost as spectacular [2], [3]. Now, magnify that from a flywheel just designed to smooth the power from a 375kW (500HP) engine to the scale of a flywheel to STORE the energy of a megawatt-scale wind turbine.
So, no, the danger of a megawatt-scale energy storage flywheel is NOT like the danger of a "giant rotating wind turbine".
[0] https://www.youtube.com/watch?v=M-o-4yYb59g [1] https://www.youtube.com/watch?v=sbCs7ZQDKoM&t=40s [2] https://www.youtube.com/watch?v=kPat3akDiek [3] https://www.youtube.com/watch?v=f4oxoBKRZgA
If you're thinking of a direct mechanical linkage, you wouldn't want to put it up on the tower because the mass to effectively store megawatt-scale power is way more than you'd want to support up high. Also, since the wind blade usually swivels to the wind, you'd want to avoid the rotational inertia. So, you'd need a mechanical linkage to transmit the power to the ground, maybe installing it under the tower base.
You would not want to use a direct mechanical attachment, i.e., resembling a combustion engine - transmission flywheel, because this would impair the ability of the wind turbine to start. Generally, turbines are designed for minimum inertia to easily start in low-wind conditions. A direct connection would impede that.
Now, we're adding a clutch-sort of mechanism, and that has its own additional complexity, weight, and energy.
Moreover, considering that we're trying to store megawatt-scale energies, we are at a large mass spinning very fast, and probably spun up with an electric motor.
So, it would seem the best way to do that would be to make a flywheel farm, with the flywheels below ground to contain failures. At this point, why locate it in the probably inconvenient location where the wind turbines are located, and instead put it somewhere more convenient, such as nearer to the consumption areas?