Ditch the Batteries: Off-Grid Compressed Air Energy Storage • Hacker News Board

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

#141

Post by maliker » Thu, May 24, 2018, 4:26 PM UTC

throwaway5752 wrote: post #82

drizzle87 wrote: post #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 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…

The utility flywheel installations I'm aware of are underground. More cost, but safer.

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

#142

Post by contravariant » Thu, May 24, 2018, 4:27 PM UTC

1024core wrote: post #67

Isn't there a loss in efficiency due to heat? Compressing air heats it up, which is lost (this is the basic principle behind refrigeration, though it doesn't use air). And then there's the loss in converting this PE back into electricity. Are these losses less than what's lost in LiON cells?

Read the article they go into this in detail.

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

#143

Post by maliker » Thu, May 24, 2018, 4:27 PM UTC

mrfusion wrote: post #131

throwaway5752 wrote: post #82

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…

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

I've seen utility installations done like this. More expensive but safer.

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

#144

Post by simonebrunozzi » Thu, May 24, 2018, 4:29 PM UTC

> "they do not require rare or toxic materials"

This benefit alone would make me hope for compressed air energy batteries to receive tons of funding, and become cost-competitive with other forms of batteries.

Also, consider that there are three important elements in a battery "economics":

1) Weight / energy density - how much energy can you store, per weight of the battery? Important for cars.

2) Volume / energy density - how much energy can you store, per volume of the battery? Important for cars as well.

3) Cost / energy stored - how much does it cost to store a unit of energy? This can also be divided into two elements: setup (e.g. the cost of producing the battery and deploying it) vs maintenance (how much does it cost to keep the battery alive, over the years?)

There are also other minor factors, such as reaction to environmental changes (e.g. temperatures, etc).

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

#145

Post by maliker » Thu, May 24, 2018, 4:34 PM UTC

drizzle87 wrote: post #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 ene…

Flow batteries are looking pretty good. Costs are coming down, and the very high (some say unlimited) cycle life could give an advantage over Li-ion for stationary applications.

On the other hand, used Li-ion from electric vehicles could be so widely available that they also win for stationary storage.

Interesting times.

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

#146

Post by jcranendonk » Thu, May 24, 2018, 4:37 PM UTC

agumonkey wrote: post #118

jandrese wrote: post #98

Earlier quoted context omitted.

This doesn't make sense at all. High pressure water can be dangerous for sure, but water based energy storage doesn't use high pressure... It's all about pumping the water uphill and then letting the water flow back down through the pump to recover the energy. At worst your house gets flooded because the containment vessel failed. Worst case with compressed air is a total disintegration of the tank, the room it's in,…

my english is flawed, I was trying to say that. Water is not pressurized but feel scarier than air for most people, so they go care free around compressed gases.

Water is pressurized. However, it is not compressed. That's an important distinction.

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

#147

Post by JackCh » Thu, May 24, 2018, 4:40 PM UTC

Cthulhu_ wrote: post #84

jandrese wrote: post #62

Earlier quoted context omitted.

For home use you also have to consider that you're basically making a bomb every time you store energy in the thing.

Eh, at least air isn't as dangerous as e.g. water would be, the tank can be / is designed to fail gracefully and there's overpressure valves.

Failed water lines can ruin your house. Failure of a compressed air vessel of sufficient size could turn your house into shrapnel flying fast enough to endanger your neighbors.

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

#148

Post by iamgopal » Thu, May 24, 2018, 4:41 PM UTC

drizzle87 wrote: post #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 ene…

Just yesterday I was talking to my friend regarding this. The key idea is, humans are really good at driving the price down to bare material cost via agressive production line automation. For e.g. without all the automation including subpart a single phone with all the technology would easily cost upwards of billion. So comparing ANY technology regarding their future prospects, we can easily deduct that which ever can be made fully automatically in production line will thrive in the end. ( Compare solar cell with all other renewable technology. Sooner or later energy produced by solar cell will bypass all other combined by tenfold or more.)

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

#149

Post by beat » Thu, May 24, 2018, 4:42 PM UTC

adrianN wrote: post #135

beat wrote: post #91

Earlier quoted context omitted.

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.

Gasoline and diesel won't leave you permanently blind on a spoonful. Methanol is significantly more poisonous. It also burns with a colorless flame, which has been a problem in auto racing, where it is sometimes used.

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

#150

Post by tossandturn » Thu, May 24, 2018, 4:54 PM UTC

ballenf wrote: post #114

dwyerm wrote: post #89

Earlier quoted context omitted.

> 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…

Also flywheels don't give off noxious fumes during failure.

...or during production (relatively speaking).