201–210 of 325 posts
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...
I would like more detail on the "Thermal management system" and how long it could store the heat it captures. One of the benefits they touting is "Long duration energy storage" I would think the limiting factor would be the ability of the thermal management system to retain the energy it captured to reheat the compressed air. Am I thinking about this correctly?
According to their marketing video [1] "Long duration" is relative to current lithium ion battery-based storage. So their system can store energy up to 24 hours vs a few hours for batteries.
For even longer term storage (weeks, months, seasons), some time of chemical storage will be needed. Currently, both hydrogen electrolysis and ammonia synthesis [2] are being explored for that.
I really enjoy learning about quirky ways to "store" energy, there is also one case that allows "storing" of energy by pushing massive concrete blocks uphill and when energy is needed, blocks simply slide down and generate energy. Not sure if this can be called "Storing" though.
The more efficient version of this idea looks like this: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
there is no rule that water+ turbines is more efficiency than Solid mass + alternators.
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
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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 isn't correct. Deep mines are notoriously hot, because you're digging towards magma. Google says temps increase by 3° C for every 100m.
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That wikipedia page answers everything you need to know about compressed air energy storage. In 2018, the tech couldn't compete against lithium ion, and the price of lithium ion continues to fall 10-20% per year. Compressed air and that concrete-block-stacking nonsense that keeps getting press are just magnets for uneducated investors.
That wikipedia page says: > Compared to traditional batteries, CAES systems can store energy for longer periods of time and have less upkeep. Sometimes the cost per MW/hr or equivalent is not the only metric worth thinking about.
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That's a really popular idea on the internet because it's very easy to grasp, but the numbers don't work out well. The weights you can actually lift aren't much compared to the volume of a reservoir of water, and the heights you can lift them are but a fraction of the thousands of meters being discussed here. Yes, the concrete isn't going to require much maintenance, but the gearboxes needed are a significant enginee…
Except it is already being done by multiple companies [0], Energy Vault in Switzerland [1], Gravitricity in Scotland [2], New Energy Lets go [3], and Gravity Power [4]. All have raised substantial funds and are building. Sure, pumped hydro has advantages, but has serious geographic limitations - you need a fairly ideal site. The key is that these can be built almost anywhere. [0] https://spectrum.ieee.org/gravity-ene…
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.
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How did the situation go from a water leak to an explosion?
The Lake Peigneur Drilling Accident is a tale of water getting into a salt mine from the lake above, due to drilling for oil in the wrong place. As the water dissolved the salt, the hole grew bigger and bigger, exponentially. The lake emptied into the salt mine, turning it into brine. https://en.wikipedia.org/wiki/Lake_Peigneur So I'm picturing water leaking into a salt mine full of pressurized air. Naively it makes…
Grid storage is going to be big business in the future, on the order of size of storage for electrical vehicles. (And these will certainly not be mutually exclusive markets! Vehicle to grid tech will become widespread, as is already seen in the new F150 Lightning truck). Lithium ion will dominate for the foreseeable future, as the industry has scaled to massive sizes and already, and has the advantage of being curren…