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Goldman Sachs invests $250M in compressed air energy storage

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Re: Goldman Sachs invests $250M in compressed air energy storage

#261

Post by PBnFlash »

ted_dunning wrote: post #227
u320 wrote: post #63

Earlier quoted context omitted.

Isn't that just pumped hydro? You would need similar masses of water.

It is pumped hydro, but you don't have the same mass of water because of the dramatically different pressures involved. Smaller water mass is the advantage to this, but the problem of managing heat is the downside that pumped storage doesn't face. This general technique is known as "liquid piston".

Thanks for the search term. I am not a huge fan of the "advanced polymer" wank of that video but liquid piston seems very practical compared most of the "air powered car" nonsense compressed air systems that show up.

Re: Goldman Sachs invests $250M in compressed air energy storage

#262

Post by enginoor »

mabbo wrote: post #194
AlexTWithBeard wrote: post #105

In early 20th century in London there was an alternative hydraulic "power grid" with plants (aka pumps), storages and an underground distribution network of pipes. A building, for example, could connect to high pressure water mains and use it to power elevators. Electricity eventually won, but it's interesting to see an idea coming back. Zeppelins next! [1] https://en.wikipedia.org/wiki/London_Hydraulic_Power_Company

This sort of system is used today in many modern industrial facilities. Case in point: Amazon warehouses. Lots of the mechanical automations inside some of those warehouses are powered by compressed air in open loop systems. As the conveyor pushes the item off, onto a different lane, there's a distinct hiss of air escaping. The movement of the machine was powered by compressed air. Out in the parking lot in these fac…

The common term is "pneumatics" and the components are prevalent in all automation and manufacturing. The air required is typically compressed on site.

Pneumatic actuators are relatively inexpensive, have a binary state that is easy to control, and offer a high power density.

Re: Goldman Sachs invests $250M in compressed air energy storage

#263

Post by nautilius »

benreesman wrote: post #94
JohnL4 wrote: post #53

Earlier quoted context omitted.

I'm guessing not. Earth's heat is way lower down. Think of a cave: always cold. I think what's going on is they're taking the heat out and storing it more efficiently than just dumping it down the ground, where (1) it would leak away, representing energy loss, and (2) as it leaks away, the air would lose pressure. (It would leak away b/c it's harder to insulate an entire mine, basically.) So, they pull it out ahead o…

This comment is an example of why I’ve become skeptical of the downvote button. It sounds like people read it, knew better, and politely pointed out that it was incorrect. Everyone who might have shared the same misapprehension learned something and the parent wasn’t being an asshole. Doesn’t that add to the discussion?

Didn't downvote, but I am not a big fan of simply making stuff up on the fly as response. I've met my share of people who rather go this route than put in a 5sec Google search or simply admit they don't know something, and I try to avoid them.

Re: Goldman Sachs invests $250M in compressed air energy storage

#265

Post by sokoloff »

danans wrote: post #208
arnaudsm wrote: post #201

Earlier quoted context omitted.

60% is great! That's much better than hydrogen, but still far from lithium. Let's hope the $/kWh is decent.

It's not quite lithium ion efficiency, but it serves a different duration energy storage market (up to 24 hours vs single hours for lithium ion battery storage), and it has a much longer service life (50 years), so the levelized cost of storage might be lower than lithium ion battery storage.

The lithium ion batteries in my car store energy for weeks on end with losses around 1-2% per week (after an initial couple percent rapid drop).

Re: Goldman Sachs invests $250M in compressed air energy storage

#266

Post by [deleted] »

cinntaile wrote: post #251
bumby wrote: post #228

Earlier quoted context omitted.

They aren't really the same types of systems. Pneumatic "muscle pressure" is common in lots of industrial applications, especially those that operate in austere environments. But those are different than the tech being researched in the article in large part because the mechanical compressors in industrial applications are hugely inefficient. Many constant volume compressors have 90%+ of the energy as waste heat. I b…

How does this work? How can you compress air without raising the pressure? Are you sure you don't mean adiabatic?

[deleted]

Re: Goldman Sachs invests $250M in compressed air energy storage

#267

Post by DuskStar »

Someone wrote: post #257
samstave wrote: post #116

Earlier quoted context omitted.

There also used to be "central turbines" whereby there was a central spinning rod that one could attach belts to in order to spin a thing to get work out of it... called line and shaft https://www.youtube.com/watch?v=7qt5tltnvF8

That was normal in the age of steam. Having lots of tiny steam engines on the factory floor does not make sense. Keeping them running is too labor intensive, they would be fire risks, and they’re less efficient.

And in the age of water, running shafts to the waterwheel was vastly easier than having a wheel at each station.

Re: Goldman Sachs invests $250M in compressed air energy storage

#268

Post by IncRnd »

AlexTWithBeard wrote: post #105

In early 20th century in London there was an alternative hydraulic "power grid" with plants (aka pumps), storages and an underground distribution network of pipes. A building, for example, could connect to high pressure water mains and use it to power elevators. Electricity eventually won, but it's interesting to see an idea coming back. Zeppelins next! [1] https://en.wikipedia.org/wiki/London_Hydraulic_Power_Company

Hydraulic refers to liquid. Pneumatic refers to compressed air.

Re: Goldman Sachs invests $250M in compressed air energy storage

#269

Post by thehappypm »

arnaudsm wrote: post #201
sauwan wrote: post #130

The round trip efficiencies for these compressed air storage have typically been terrible ( ETA: Just saw the video. Looks like they store the heat to boost generation on the return trip. This [1] says they get ~60% efficiency. [1] https://www.inceptivemind.com/hydrostor-build-largest-compre...

60% is great! That's much better than hydrogen, but still far from lithium. Let's hope the $/kWh is decent.

Especially when you consider that the use case here is surplus energy, like when the wind is blowing harder than can be consumed. Efficiency might not be so important if you’re buying free wind or solar energy, as long as it’s above some minimum threshold. 60% feels pretty good.

Re: Goldman Sachs invests $250M in compressed air energy storage

#270

Post by belorn »

EricE wrote: post #167
belorn wrote: post #19

How does the economics of this look like, and how do they intended to get back the investment. If its to buy low when wind/solar production is high and sell when production is low, what will the cost per watt be? If its subsidies, how much will this cost the government? The article seem to mostly describe this as a technology project to test the technology at scale, but they do also mention profits. Is the basic prem…

Energy storage if you want to rely solely on renewable energy sources is THE KEY to making that even remotely feasible. Current solar and wind renewables are NOT predictable nor reliable for sustained power generation. With Coal, Natural Gas, Nuclear and Hydro you can generate power on demand, no matter what the environment is doing. Well, Hydro in the west is getting dicey with the drought - but even that is far mor…

The question is still economics. At minimum the cost per watt/h need to be cheaper than to build a nuclear plant and have it run when demand exceed supply from renewables. Is this true for compressed air?

When people discuss green hydro as a storage solution the numbers so far, from what I have managed to interpret, is around 3-5 times that off nuclear for the same amount of energy delivered. It is still technically possible to make a profit given enough subsidies and time, and it get much more economically if the hydrogen can be used directly in the production chain like steel and fertilizer. Right now there are a steel foundry in Sweden testing the technology and economics doing that, through I don't know how much subsidies and tax reductions were involved.

Which all means the question about economics remains. There are many alternatives to fossil fuels but the primary question everyone debates is the issue of price. Without a price per watt/h or a time frame for when the investment get repaid its impossible to separate the practical from impractical, and the subsidy question is very relevant when discussing this on a national level.

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