WingNews logo WingNews
top | item 23621677

(no title)

arussellsaw | 5 years ago

Compressed air storage seems like a really appealing method, especially considering the low carbon footprint and massively longer lifetime than lithium batteries. This post covers it quite well https://solar.lowtechmagazine.com/2018/05/ditch-the-batterie... , I’d be really keen to see if compressed air can also be successful for independent households looking to go off grid or reduce dependence on the grid.

discuss

order

lend000|5 years ago

While it is appealing compared to many alternatives and is more portable for smaller settings, when used on an industrial scale like this giant battery, I wonder how it compares in overall utility to gravity batteries [0].

The nice thing about gravity batteries is that they can form a closed loop with water supply, too, pumping reclaimed water back up into reservoirs when there's excess power. I'd expect compressed air to have much higher energy density, but it would be interesting to see if anyone has the numbers.

[0] https://en.wikipedia.org/wiki/Gravity_battery

ashtonkem|5 years ago

Pumped water batteries are geographically limited, since they can basically only be installed wherever you could build a dam anyways.

gnramires|5 years ago

Those methods are actually quite similar, they're all ultimately related (limited by) tensile strength of materials. So costs and specific energy densities (per construction material unit) are similar. An important figure is cost/tensile strenght I guess.

(Compressed air: limited by container tensile strength; gravity batteries: limited by strength of cables)

I suspect even the constants involved are the same (given the materials are almost uniformly under nominal load), although I don't have time to investigate right now (a good curiosity research topic!).

sa1|5 years ago

In my country, there are economic challenges: water isn't available everywhere, diverting water is not cheap, and it messes with water sharing agreements, which are a political issue in themselves.

sandworm101|5 years ago

It has its own issues, not the least of which is safety. There is lots of energy in compressed air, that's the point. I would look heavily into the risks of structural fatigue. A lithium ion battery might catch fire, but an "air battery" can go boom.

alex_duf|5 years ago

Given that anything that contains energy can go boom, I think of all of them this one doesn't sound too bad. Probably local casualties but no risk of cancer for the next century, or ground pollution for the next decades.

verelo|5 years ago

Isn’t this the issue with any large battery? Water in large volumes can cause a lot of damage too. I suspect it’s hard to find a large battery that isn’t scary when mishandled.

throwaway0a5e|5 years ago

Literally anything you store energy in is going to have the same safety issue. You can muck around with space efficiency and peak wattage but at the end of the day you've got the same amount of joules that want out and if they get out in an uncontrolled manner it will be bad.

woodandsteel|5 years ago

This plant is not using compressed air, it's using liquified air.

thinkcontext|5 years ago

Several startups have tried and failed. Most notable was Lightsail which raised $80M from Gates, Thiel, etc.

dhimes|5 years ago

IIRC LightSail was founded by our own very brilliant Dani Fong.