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Geothermal may beat batteries for energy storage

spectrum.ieee.org

291–293 of 293 posts

Re: Geothermal may beat batteries for energy storage

#291

Earlier quoted context omitted.

Would you be able to help me figure out the gravitational potential energy of the red hill tanks? https://www.epa.gov/red-hill/what-red-hill-bulk-fuel-storage... They were recently decommissioned due to leaks, but I've often wondered if they could be repurposed as gravity battery storage. edit: if you want to check my math. I calculated the tanks at ~567 million liters, and am saying there is 120 meters of vertical d…

I think a bit more than that, the article says 250 million gallons which is more like 960 million litres. That squares with the dimensions given: 15m x 15m x pi x 75m x 20 tanks = 1 million cubic metres = 1 billion litres. Oahu uses about 225MW on average in residential electricity [0], so this could store an hour or so of excess capacity. That's not nothing, but you might want to 5x or 10x it to really smooth out de…

I subtracted 100 from their position on red hill at 220-ish meters to account for the fact that the tanks are buried in the ground (I don't know precisely where).

>Oahu uses about 225MW on average in residential electricity [0], so this could store an hour or so of excess capacity. That's not nothing, but you might want to 5x or 10x it to really smooth out demand and supply peaks for the island.

https://spectrumlocalnews.com/hi/hawaii/top-stories/2022/08/...

This solar plant & battery system was completed last month. The battery is able to store 144 MWh. This shows me that planners and people thinking about this are willing to invest & commit to power solutions at this scale. I don't know if you are aware or have read up on the red hill controversy. These tanks were used to store fuel by the Navy. They leaked earlier this year and poisoned the Red Hill aquifer and have caused quite a bit of local controversy.

I'm struggling with the idea of writing a letter to the editor outlining this concept, but also emphasizing how converting these tanks to a water storage/ energy storage facility would improve local resilience to drought, bring down water costs, improve environmental conditions etc.

Re: Geothermal may beat batteries for energy storage

#292
post #196
post #173

Earlier quoted context omitted.

You're right it isn't, but it is storing the water on top of the house.

Yes, but I'd expect it's much lesser amounts. 80 gallons is a decent sized water heater.

ahhh i understand what you were saying now.

Re: Geothermal may beat batteries for energy storage

#293

Earlier quoted context omitted.

Completely agree with the hybrid approach wrt reducing emissions. I am talking more towards work that would be done concurrently with that. > During this build all storage technologies where they make the most sense so that when that last 10% is needed, prices will have dropped this is kind of the point of what I'm getting at. Without any investment, none of the storage technologies are going to make much progress. I…

In terms of promising technologies, they're broadly categorisable as thermal, kinetic, battery/fuel cell, and thermochemical. Most of the promising ones are far enough along the learning curve that other markets (such as green hydrogen/ammonia for fertiliser driving electrolysers and small scale/more efficient chemical reactors) will drive the learning curve. Thermal storage concepts include: Molten salt thermal. sho…

CAES (Compressed Air Energy Storage)

"Compressed air storage vs. lead-acid batteries" (2022) https://www.pv-magazine.com/2022/07/21/compressed-air-storag... :

> Researchers in the United Arab Emirates have compared the performance of compressed air storage and lead-acid batteries in terms of energy stored per cubic meter, costs, and payback period. They found the former has a considerably lower CAPEX and a payback time of only two years.

FWIU China has the first 100MW CAES plant; and it uses some external energy - not a trompe or geothermal (?) - to help compress air on a FWIU currently ~one-floor facility.

Couldn't CAES tanks be filled with CO2/air to fight battery fires?

A local CO2 capture unit should be able to fill the tanks with extra CO2 if that's safe?

Should there be a poured concrete/hempcrete cask to set over burning batteries? Maybe a preassembled scaffold and "grid crane"?

How much CO2 is it safe to flood a battery farm with with and without oxygen tanks after the buzzer due to detected fire/leak? There could be infrared on posts and drones surrounding the facility.

Would it be cost-advisable to have many smaller tanks and compressors; each in a forkable, stackable, individually-maintainable IDK 40ft shipping container? Due to: pump curves for many smaller pumps, resilience to node failure?

If CAES is cheaper than the cheapest existing barriers, it can probably be made better with new-gen ultralight hydrogen tanks for aviation, but for air ballast instead?

Do submarines already generate electricity from releasing ballast?

(FWIW, like all modern locomotives - which are already diesel-electric generators - do not yet have regenerative braking.)

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