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Ditch the Batteries: Off-Grid Compressed Air Energy Storage

lowtechmagazine.com

21–30 of 238 posts

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#21

So, I seem to recall that the Amish sometimes use something like this to power their tools. Source: my own unreliable memory of an article I read somewhere. Anybody more knowledgeable out there able to confirm or disfirm?

Not a hard confirm, but I stood there marveling at the pneumatic ceiling fans in an Amish bakery once. Each one had a little oscillating engine and some plumbing for the compressed air.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#22

An early design for the automobile ran on compressed (liquid!) air. http://www.didik.com/ev_hist.htm It might work for some applications, but in 120 years we haven't been able to make it work for cars, at least.

> ... but in 120 years we haven't been able to make it work for cars...

Ok, but has anyone worked on the problem in the past 120 years?

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#23

Earlier quoted context omitted.

In the midwest, running compressed air through a home is called amish electricity. They do use it for many things. Ive seen air-powered blenders. (Air power is a big thing for woodworking and so its use in the home too is no suprise.)

I had no idea these existed, I want these when I move back off-grid. https://www.cottagecraftworks.com/kitchen-food-prep/non-elec...

It is functional but has many issues. Water/condensation in the lines is a big deal in winter. Running pipes in walls makes leak detection difficult. They are all also very very loud.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#24
I was quite excited by compressed air storage when Lightsail came into the picture almost 5-7 years ago. Sadly, they could not make the economics work and ended up pivoting into a company that sells carbon fibre tanks for high-pressure storage.

As someone who follows the energy space closely, Lithium ion batteries now have so much momentum and $$$ pumped into them via R&D work, it's going to be hard for competing energy storage technologies to catch up. Flywheel and hydrogen fuel-cell also often come up but I think we're at a point now where batteries are going to take off simply because of their wide area of applicability. With that economy of scale costs will drive down and even more research and $$$ will flow.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#25
post #20

When compressing air, a lot of heat is generated, and in most cases wasted. When the air is released, it cools down, and has to take heat from the surroundings. Which doesn't work very fast without additional heat exchangers, and especially not in cold environments. Compressed air storage is only efficient with additional heat storage, which is something that promoters of compressed air storage often "forget" to tell…

Did you read the article? All of that is in like the first paragraph.

What the parent said was still useful I think to people who might not know this particular trope throughout the industry.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#26
At ETH Zurich, there is a project aiming at scaling compressed air storage to MWhs. [1]

The interesting part is that they are trying to make the storage adiabatic, i.e., they store the heat that is generated while compressing the air in a phase change material (i.e., a material that will become liquid when hot, since a lot of energy can be stored in phase transitions) and get the heat back to warm up the cold expanding gas on decompression.

The issue is that even with the phase change storage, heat will dissipate into the rock within a couple of days, making the whole process inefficient for long-term storage.

[1] https://www.ethz.ch/content/specialinterest/mavt/energy-tech...

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#27

So, I seem to recall that the Amish sometimes use something like this to power their tools. Source: my own unreliable memory of an article I read somewhere. Anybody more knowledgeable out there able to confirm or disfirm?

Maybe the article was 'Amish Hackers' by Kevin Kelly?

[0] http://kk.org/thetechnium/amish-hackers-a/

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#28

Earlier quoted context omitted.

Similar to those gravity power modules: a company called Ares ( https://www.aresnorthamerica.com/ ) is trying to use much smaller concrete 'cars' on rails to store energy. Not sure of the status of it but it looked promising to me. The direct use of compressed air is interesting. Taking it to the extreme, you could have compressed air as your primary utility piped through your home, and have appliances that run off c…

Nah, there's water-based computers, there could be compressed air computers. Picturing the different logic gates running on compressed air is a hoot.

You should check out Ted Chiang’s story “Exhalation.”

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#29

I was quite excited by compressed air storage when Lightsail came into the picture almost 5-7 years ago. Sadly, they could not make the economics work and ended up pivoting into a company that sells carbon fibre tanks for high-pressure storage. As someone who follows the energy space closely, Lithium ion batteries now have so much momentum and $$$ pumped into them via R&D work, it's going to be hard for competing ene…

My concern with batteries is we're so gung ho on producing these, we haven't stopped to consider the environmental impact from the manufacturing process or the incredible task of recycling these once they've outlived their usefulness.

It reminds me a lot of when people pushed plastic for everything in order to save the trees and reduce paper consumption. Some 40 years later, we're now trying to get off plastic and dealing with massive environmental issues surrounding nearly every kind of plastic.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage

#30
post #3

An added benefit is you could power your air-tools with something like this without having to convert to electrical energy. As a former off-gridder, that's actually a really big plus. Another non conventional way to store energy is using gravity power modules (example: http://www.gravitypower.net/ ) Storing hydrogen from electrolysis via solar panels also sounds interesting. Basically once your batteries are charged…

My knowledge of physics is very basic and practical engineering is zero, but storing hydrogen in compressed tanks always seem very impractical to me. It's the most freaking volatile element in the universe. And atomic hydrogen reacts with pretty much anything. Leakage and corrosion.

From my armchair perspective, storying it in chemical bonds (like nature does) makes a lot more sense.

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