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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

#281

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

A bit tangential, but New York City has an operating steam system that's still widely used by commercial customers. https://en.wikipedia.org/wiki/New_York_City_steam_system

It is funny (if not terrifying) that we have literal geysers spring up on crowded city streets every once in a while.

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

#282

Earlier quoted context omitted.

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.

How do they avoid bacteria/mould from growing in tanks and flocking the pipes and releasing in the room? Do such systems ever get cleaned up?

The air in industrial pneumatic systems is filtered and dried, which would prevent these issues.

Pneumatic systems often use small orifices and valves to control the air flow which would be quickly clogged by any debris, so cleanliness is important.

An aside: PID control was, back in the day, mostly implemented in pneumatic control systems (using a set of levers, bellows springs and nozzles). Pneumatic control systems were (and still are) used a LOT in industrial control systems where e.g. flammable environments where electrical equipment is too much of a risk.

https://control.com/textbook/closed-loop-control/pneumatic-p...

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

#283
post #254

Earlier quoted context omitted.

District heating is pretty normal at northern Europe altought now we use mostly water.

District heating with water is vastly more safe, I imagine that's why its used. I remember my apartment in germany had a "Heat" meter on the water line, always wondered how that worked.

We have a calorimeter - it should count volume of hot water times the temperature difference. I heard it's not very precise.

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

#284

Earlier quoted context omitted.

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.

How do they avoid bacteria/mould from growing in tanks and flocking the pipes and releasing in the room? Do such systems ever get cleaned up?

[deleted]

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

#285

Earlier quoted context omitted.

Can you name a method of large scale energy storage that isn't dangerous if done incorrectly?

I think the comment is more about being easy to do incorrectly/dangerously. Pumping water up into a reservoir seems easier/safer.

You’ve picked the one that probably has the highest death toll worldwide!

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

#286

Earlier quoted context omitted.

A bit tangential, but New York City has an operating steam system that's still widely used by commercial customers. https://en.wikipedia.org/wiki/New_York_City_steam_system

District heating is pretty normal at northern Europe altought now we use mostly water.

The district heating in Brno here in Czech Republic is in the process of converting from steam to hot water, mainly due to cost savings. Modern isolated hot water pipes loose a negligible ammount of heat in transfer while there was green grass growing on top of the old buried steam pipes even in winter.

That and the old textile industry that directly used steam no longer exists.

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

#287
post #58

Earlier quoted context omitted.

It says repurposing old mining operations. Not sure how feasible that is.

I had a similar idea for repurposing an old mining operation. You take a closed gold, uranium or copper mine which is 1000-2000 meters deep. You create a nuclear rector at the bottom with "fire and forget" design. Only robots can do the maintenance. After 60 years you disable it, pour concrete into the shaft and move to the next location. If it melts, who cares? It's not gonna poison water supply. Why was this not bu…

In France we’re storing highly radioactive items underground. Here is how dissipation works:

- After a few dozen years, the concrete is expected to breach,

- Radioactive atoms mix up with soil and dissipate both upwards and downwards, mostly thanks to water,

- After 400 years and for thousands of years, they reach the surface, where they should be diluted enough to not be dangerous,

So I guess having badly contained radioactive containers would be much worse.

One thing to remember is that pressure underground is extremely high (stone weighs a lot more than water, and light rock tends to “float” onto denser rock). If a melted reactor were squeezed, it would spread materials into the soil much quicker.

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

#288
post #38

Can someone explain their revenue to me? They claim 1m in revenue from their existing product which is: "1.75 megawatts (MW) of peak power output; a 2.2 MW charge rating; and 10+ megawatt-hours (MWh) of storage capacity" How does that equal 1m in revenue? You have to pay to charge your air-battery during low-cost hours and then discharge it during high cost hours to make the difference in revenue. The issue is, you c…

I agree it does seem like a stretch. IF 10MWh is their daily cycle, they are selling 3,650,000 kWh/year. To hit $1M per year, they would need to be selling ~27c/KWh above their buying price. I get that you can have a big spread if you are being paid to take power, and paid again to sell it.

I think that’s it basically. New England consumers pay ~$.22/kWh. We’re going to have offshore wind energy in the next decade that might conceivably have surplus power quite a lot. It’s not beyond the realm of possibility that these plants could have a deal with the power plants to take extra power for free so long as they have guarantees on filling the expected gaps or meeting expected spikes in usage. Everyone wins.

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

#289
post #85

Earlier quoted context omitted.

I think the comment is more about being easy to do incorrectly/dangerously. Pumping water up into a reservoir seems easier/safer.

Lots of water in a reservoir is not particularly safe in itself. For example, in December 2000 at the Grande Dixence a high-pressure pipeline from the dam burst, causing a landslide that wiped out a small hamlet and killed three people. It's also not hard to find reports of massive amounts of casualties and/or property damage from dams that just outright fail.

An underground reservoir of water though should still be safer. Only the operator(s) on site might be impacted by a failure.

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

#290
post #219

Earlier quoted context omitted.

https://www.nationalgeographic.org/encyclopedia/crust/ Not sure about the rate per-mile, but literally it's that hot, yes, but not even 15 miles. Just down 5-7km under the oceans, for example at the Mohorovičić discontinuity the temp ranges from 392 to 752F.

Under the ocean is already much, MUCH closer however to the mantle. Oceanic crust is drastically thinner than the land we walk on. In the Nat Geo article they quote a mine in South Africa reaching up to 55C (131 F) at the bottom and the mine is 4km deep. At a rate 3 degrees Celsius per 100m it should be 120 degrees Celsius over ambient. Which obviously does not add up.

They reached 160C rock when building an industrial railway in Japan:

https://en.m.wikipedia.org/wiki/Kurobe_Seny%C5%8D_Railway

Cooled down to 40C since the 60s.

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