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Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

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Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#51

Post by shrubble »

aspenmayer wrote: post #39
Animats wrote: post #6

Earlier quoted context omitted.

Flywheel energy storage has been proposed many times, and built a few times. Flywheel-powered buses have been deployed. Not too successfully. EMALS uses a big flywheel to power aircraft carrier catapults. The flywheel energy storage seems to cause most of the problems. The next generation of that system may use ultracapacitors.[1] [1] https://www.ga.com/capacitors/military-mil-spec-capacitors

It seems that the flywheel is a monolithic system , and the proposed next gen ultracapacitor is a modular system . You probably only have one giant flywheel, as the mass is where the energy storage gains make it worthwhile. Maybe you have many of them in parallel, but the size would make scaling an issue. Not to mention that there’s an associated drivetrain and linkages and so on. It’s a fully integrated contraption.…

It's not monolithic vs modular...it's controlling a large amount of angular momentum / kinetic energy instead of... not having to do that.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#52

Post by sarthakjshetty »

There was a company called LightSail Energy [1] that tried to (unsuccessfully) commercialize this technology. Does anyone know what happened to it? Some searches online show that they had some founder problems. IIRC, they had great investors, but unfortunately it didn't work out.

[1] - https://en.wikipedia.org/wiki/LightSail_Energy

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#53

Post by hinkley »

mycall wrote: post #45
lopmotr wrote: post #43

Earlier quoted context omitted.

Energy density is only one factor. Cost per kWh is more important for people with plenty of land.

Have fun making something as big as a large house without leaking air, for each installation.

That’s the thing about pressure. A pressure vessel doesn’t care if it’s holding back enough gas to equal five cubic yards at 1 atmosphere, or 5 million cubic yards. It only cares that it’s at 3 bars or five.

You’re right, a vessel the size of a battery array is stupid. Because it’s all surface area and no volume, compared to a vessel the size of an aircraft, or a small stadium. You’d build one of these for an area of town, and the “size” that matters for stationary centralized equipment is not the displacement but the volume of material to make up the skin, the valves, the generator, and the piping to connect it all.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#55

Post by unnouinceput »

tzs wrote: post #36
diego_moita wrote: post #11

Slightly of-topic: compressed air is the preferred source of power for the tools of Amish people, since their religion doesn't allow them to use electricity or internal combustion engines. https://www.cottagecraftworks.com/home-goods/self-sufficient...

Most Amish sects do not prohibit electricity. It is not uncommon for them to have electrical devices powered by solar panels. I don't think most have anything against internal combustion engines. As your own link notes, they might use such engines to power air compressors. What concerns the Amish is being too dependent on the outside world. Tying to the regional electrical grid would make them too dependent. They are…

Hooolyyy craaap!! That was a good read, thank you.

Quote: "Ivan is an Amish alpha-geek. He is always the first to try a new gadget or technique. He gets in his head that the new flowbitzmodulator would be really useful."

flowbitzmodulator!! That's my new word for this week...my wife's going to kill me

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#56

Post by therockspush »

ortusdux wrote: post #23
diego_moita wrote: post #11

Slightly of-topic: compressed air is the preferred source of power for the tools of Amish people, since their religion doesn't allow them to use electricity or internal combustion engines. https://www.cottagecraftworks.com/home-goods/self-sufficient...

I've been obsessed with technology that skirts religious laws for a while now. Whole house pneumatic systems to run $800 dollar non-electric blenders. Elevators that spend the sabbath atomically opening on each floor. Automatic timers to complete forbidden circuits. I would love to spend an hour or two with a rabbinical scholar. Does walking in front of a motion senor complete a circuit? Are you allowed to ask an AI…

This stuff cracks me up. Do they think Hashem is up there looking down, thinking "Good one guys. You got me there. I thought I had all my bases covered. I'll save you some extra latkes when you get here."

Someone help me understand why some folks treat this stuff like a tax loophole.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#57

Post by grawprog »

diego_moita wrote: post #11

Slightly of-topic: compressed air is the preferred source of power for the tools of Amish people, since their religion doesn't allow them to use electricity or internal combustion engines. https://www.cottagecraftworks.com/home-goods/self-sufficient...

I personally think compressed air tools are underrated. I worked at a shop that used a lot of compressed air powered 'things'. We had a bunch of air powered hand tools that out performed electric equivalents by a fair bit. Most of the larger machines, though mostly electrically driven, had major components that were air powered and required a compressor.

The force and energy available through natural physical processes is under rated some times...

Well...I guess all our power and energy is based on natural processes.

Hmmm...I guess...there's some natural physical processes that tend to get largely overlooked that provide more energy than one might think is I guess what I mean.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#58

Post by nine_k »

grawprog wrote: post #57
diego_moita wrote: post #11

Slightly of-topic: compressed air is the preferred source of power for the tools of Amish people, since their religion doesn't allow them to use electricity or internal combustion engines. https://www.cottagecraftworks.com/home-goods/self-sufficient...

I personally think compressed air tools are underrated. I worked at a shop that used a lot of compressed air powered 'things'. We had a bunch of air powered hand tools that out performed electric equivalents by a fair bit. Most of the larger machines, though mostly electrically driven, had major components that were air powered and required a compressor. The force and energy available through natural physical process…

You can expend any part, up to 100%, of the entire charge of a compressed air tank, momentarily. You can get a lot of power (measured in Watts) from it.

An electrical battery, even if it stores the same amount of energy, is seriously more power-strapped.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#59

Post by jandrese »

I'm not a fan of this personally. Compressed air is dangerous. A full tank is basically a bomb. While we have the technology to make this safe, it has to be regularly inspected. If your homeowner slacks on the inspections they could come home one day to discover their energy storage has turned itself into a crater and flattened all nearby structures.

One thing to consider is that the heat generated by compressing the air could be vented into the home to warm it up in the winter, or simply allowed to escape outside in the summer. When discharging the cool air would either be released outside or inside of the home, depending on if you want to cool it off.

Re: Ditch the Batteries: Off-Grid Compressed Air Energy Storage (2018)

#60

Post by nine_k »

therockspush wrote: post #56
ortusdux wrote: post #23

Earlier quoted context omitted.

I've been obsessed with technology that skirts religious laws for a while now. Whole house pneumatic systems to run $800 dollar non-electric blenders. Elevators that spend the sabbath atomically opening on each floor. Automatic timers to complete forbidden circuits. I would love to spend an hour or two with a rabbinical scholar. Does walking in front of a motion senor complete a circuit? Are you allowed to ask an AI…

This stuff cracks me up. Do they think Hashem is up there looking down, thinking "Good one guys. You got me there. I thought I had all my bases covered. I'll save you some extra latkes when you get here." Someone help me understand why some folks treat this stuff like a tax loophole.

AFAIK the Jewish covenant with God is much more like a legal contract than a moral / conscientious obligation. So a tax loophole may be an apt comparison.
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