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Goldman Sachs invests $250M in compressed air energy storage

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71–80 of 325 posts

Re: Goldman Sachs invests $250M in compressed air energy storage

#71

Earlier quoted context omitted.

Totally out of my depth here, but does cooling the gas down have the added benefit that it'll be heated by the earth whilst stored?

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.

Wouldn't the cooled down gas expand when heated leading to higher pressure, so you need to pump gas down?

Re: Goldman Sachs invests $250M in compressed air energy storage

#73

Earlier quoted context omitted.

I wonder what is the loss/recovery %age.

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/.

Re: Goldman Sachs invests $250M in compressed air energy storage

#74
post #56

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 p…

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.

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.

Re: Goldman Sachs invests $250M in compressed air energy storage

#75
post #5

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 myria…

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.

Re: Goldman Sachs invests $250M in compressed air energy storage

#76
post #38

Can someone explain their revenue to me? 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 c…

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…

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?

Re: Goldman Sachs invests $250M in compressed air energy storage

#77
post #59

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?

On that note do you have a good explanation for why the air needs to be reheated? I didn't quite understand that from the video.

Re: Goldman Sachs invests $250M in compressed air energy storage

#78

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 curren…

Seems like everyone wants to make everything in Rust these days! /s

Re: Goldman Sachs invests $250M in compressed air energy storage

#79
post #70

Can someone explain why this is better than just using pumps to pump water up from the reservoir and extract the energy with when the water returned back?

It requires less surface area, both due to compressibility and due to hydrodynamics. Additionally, water is a strong erosion source, air is not, so this can make use of existing excavations much easier and deep excavation is very very expensive.

Re: Goldman Sachs invests $250M in compressed air energy storage

#80
post #59

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?

On that note do you have a good explanation for why the air needs to be reheated? I didn't quite understand that from the video.

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.
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