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Ditch the Batteries: Off-Grid Compressed Air Energy Storage

lowtechmagazine.com

131–140 of 238 posts

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

#131

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…

There's a video somewhere of a failing flywheel, it's a fairly energetic explosion. I follow the energy space, also, and ... while I didn't expect Li batteries to have grid scale roles, I didn't think flywheels were going to succeed there. They have properties more like ultracapacitors (discharge rate suitable for continuous backup, clean up messy grid sine waves). I thought pumped air/pumped water was more likely be…

Why can’t we bury flywheels to protect from any explosions?

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

#132
post #31

> However, to store 360 Wh of potential electrical energy, the system requires a storage reservoir of 18 m3, the size of a small room measuring 3x3x2 metres. The authors note that “although the tank size appears very large, it still makes sense for applications in rural areas”. This would light a home for an hour, with LED bulbs and careful usage. And all it requires is a room-sized storage tank. So if I wanted somet…

My four lb lawnmower batter stores 120wh. Quite the contrast.

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

#134

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…

Aren't flywheels used in datacenters to cover the split second between when the power goes out and the generators kick on?

Only some of them have flywheels. The large telco datacenter I visited had huge pallets of batteries to cover the time needed for the diesel generator to start.

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

#135
post #91
post #43

Earlier quoted context omitted.

It's not really efficient, but you can create short chain hydrocarbons to store fuel for your fuel cell. Methanol for example is a lot easier to handle than hydrogen and there are fuel cells that consume it.

Methanol is avoided in a lot of non-industrial situations because it's so incredibly toxic. Very dangerous to children and animals and idiots.

I wouldn't recommend drinking gasoline or diesel either, but cars seem to work pretty well with it.

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

#136
post #31

> However, to store 360 Wh of potential electrical energy, the system requires a storage reservoir of 18 m3, the size of a small room measuring 3x3x2 metres. The authors note that “although the tank size appears very large, it still makes sense for applications in rural areas”. This would light a home for an hour, with LED bulbs and careful usage. And all it requires is a room-sized storage tank. So if I wanted somet…

> This would light a home for an hour, with LED bulbs and careful usage.

Do you have the equivalent of 50 LED bulbs (60W equivalent [1]) burning at a time? Do you consider that careful usage?

[1] https://www.amazon.com/Philips-Classic-Glass-Non-Dimmable-Li...

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

#137

Earlier quoted context omitted.

In a sense then you could say it's the Javascript of energy storage. Not the best on technical merits alone, but good enough along with a massive force of investment and wide adoption.

I think the surname of John B. Goodenough, one of the early Li-ion pioneers, is apt for the status of the technology.

I'll be damned, this wasn't a troll. Today I learned...

https://en.wikipedia.org/wiki/John_B._Goodenough

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

#138
> The low efficiency is mainly since air heats up during compression. This waste heat, which holds a large share of the energy input, is dumped into the atmosphere.

Wait... wait... I'm... not sure I believe the extend of this statement. If this isn't wrong it's certainly awkwardly worded.

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

#139

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 expandi…

Sounds like a promosing solution for averaging out daily fluctuations though.

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

#140
post #89

Earlier quoted context omitted.

There's a video somewhere of a failing flywheel, it's a fairly energetic explosion. I follow the energy space, also, and ... while I didn't expect Li batteries to have grid scale roles, I didn't think flywheels were going to succeed there. They have properties more like ultracapacitors (discharge rate suitable for continuous backup, clean up messy grid sine waves). I thought pumped air/pumped water was more likely be…

> it's a fairly energetic explosion So is a lithium battery explosion. So is a gasoline explosion. So is a flour mill explosion. So is a wind turbine explosion. Energy is energy, and losing control of energy is never great, no matter where it comes from. So while I catch your meaning, it might be better to phrase it with respect to how controllable that energy is. From what I know of flywheel storage, the problem mos…

>So is a flour mill explosion

Having witnesses a corn silo explosion, I was unprepared for the ferocity of that ignition.

>So is a wind turbine explosion

Off to YouTube...

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