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Alphabet spinoff Malta raises $26M for technology to store power in molten salt

bloomberg.com

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Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#111

Post by ams6110 »

antidesitter wrote: post #17
ams6110 wrote: post #16

Earlier quoted context omitted.

How can energy be stored as cold? Cold is by definition the absence of energy.

Temperature differences are what drive heat engines, i.e. you need a hot and a cold(er) reservoir. A nice demonstration of this is a handheld Stirling engine, which you can power by placing ice at the bottom (since it’s colder than the surrounding environment).

Okay, but technically you're storing the energy in the environment, not in the cold reservoir. Maybe a distinction not worth making.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#112

Post by cityzen »

nopinsight wrote: post #100
Bombthecat wrote: post #97

Just a question: why does a sub from Google need to raise money? I would question the confidence if a super big company starts something and is like: uh you know. We collect money from someone else.

For partnerships in an industry with powerful entrenched interests? An analogous example is the Amazon/Buffett/JP Morgan partnership in healthcare.

So just rich people being rich?

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#113

Post by stvswn »

Bombthecat wrote: post #97

Just a question: why does a sub from Google need to raise money? I would question the confidence if a super big company starts something and is like: uh you know. We collect money from someone else.

It makes a lot of sense -- it's possible that this ends up being a very viable, scaled business with low margins. If the margins are lower than Alphabet enjoys as a whole, and if there isn't an argument for synergies with existing Alphabet businesses, it could simultaneously be a very good opportunity but also not accretive for Alphabet share holders. Part of the restructuring of Alphabet/Google and the hiring of Ruth Porat was to be more disciplined about not doing everything possible with shareholder money. $24M here, $24M there, sooner or later you're talking about real money.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#114

Post by Someone »

Bombthecat wrote: post #97

Just a question: why does a sub from Google need to raise money? I would question the confidence if a super big company starts something and is like: uh you know. We collect money from someone else.

It’s a good way to verify that your moonshot project is viable, and not just a hobby of somebody who, some time ago, managed to convince management an idea is worth working on.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#115

Post by londons_explore »

occamrazor wrote: post #103
londons_explore wrote: post #96

Earlier quoted context omitted.

Your memories are wrong... An ideal heat pump is fully reversible with no energy loss.

Maybe, but I clearly remember that it is not possible to have a reversible process wich only transfers heat from a colder body to a warmer one. The third law also gives quantitative bounds to the reversibility of such processes. Heat pumps with efficiency above 1 rely on heat transfer between external bodies (e.g. from a subterranean water source to the atmosphere forhome heating systems), but this does not seem to b…

You are thinking of the carnot limit.

>It provides an upper limit on the efficiency that any classical thermodynamic engine can achieve during the conversion of heat into work

The word 'efficiency' here is misleading... If one reverses the process, converting work back into heat, you get back all the original energy in an ideal machine (and real machines, for example gas turbines, are within ~15% of ideal for the temperature & pressure change between input and output)

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#116

Post by londons_explore »

londons_explore wrote: post #78
jkravitz61 wrote: post #73

Earlier quoted context omitted.

From the description, it sounds like a giant Peltier device, not a steam turbine (otherwise why would they care about having a cold tank?). Solar farms also have a ton of space in between turbines so I’m not sure that metric is relevant. Additionally, since this device uses very safe materials (salt and coolant), there’s no reason you couldn’t dig a really big hole and shove the device inside...it would also provide…

It uses gas compression through staged compressors to make the hot side, and gas expansion through staged expanders for the cold side, which makes a loop. Think of it like a scaled up, reversible refrigerator. I'd like to know if they also have a 'medium temp' tank, since if they do, they can keep the temperatures of the hot and cold tanks constant, and just change the amount of molten salt in them. That in turn mean…

To follow up here, having read the paper, they have two 'medium temperature' tanks (for the hot and cold side materials, which are different). The turbines do indeed work at constant input and output temperature, and at constant flow velocity and therefore wattage.

The paper suggests changing the pressure of the working fluid to adjust load, but I suspect it is hard to design a turbine to be efficient at a wide range of working pressures, so instead they'll end up with many parallel turbines, and just switch some off to get less energy produced.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#118

Post by nradov »

ramblerman wrote: post #51

The neat little graph showing the rise in global yearly investments up to 2040 is amusing. Nassim Taleb has made me very wary of these things. what's even the calculation behind a projection like that, it even has a little spike in 2035!

I'm guessing it's because the scheduled restrictions on sales and use of ICE vehicles will really kick in around that time. So there will be a corresponding higher demand on the electric grid caused by a growing fleet of electric vehicles.

But obviously it's somewhat speculative.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#119

Post by occamrazor »

londons_explore wrote: post #115
occamrazor wrote: post #103

Earlier quoted context omitted.

Maybe, but I clearly remember that it is not possible to have a reversible process wich only transfers heat from a colder body to a warmer one. The third law also gives quantitative bounds to the reversibility of such processes. Heat pumps with efficiency above 1 rely on heat transfer between external bodies (e.g. from a subterranean water source to the atmosphere forhome heating systems), but this does not seem to b…

You are thinking of the carnot limit. >It provides an upper limit on the efficiency that any classical thermodynamic engine can achieve during the conversion of heat into work The word 'efficiency' here is misleading... If one reverses the process, converting work back into heat, you get back all the original energy in an ideal machine (and real machines, for example gas turbines, are within ~15% of ideal for the tem…

Thanks for the clarification. I still have issues understanding the intermediate stage, where the world is entirely and reversibly converted into a temperature differential. I might have to go back to drawing T-S diagrams.

Re: Alphabet spinoff Malta raises $26M for technology to store power in molten salt

#120

Post by anonuser123456 »

fierro wrote: post #72

loving all these armchair scientists thinking they've found "the" flaw in a company they read one article about

To be fair, for every 1000 claimed energy breakthroughs, 1 succeeds. Being skeptical of any claim before it scales in the market is somewhat rational.
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