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A near 100pct renewable grid for Australia is feasible and affordable, with just a few hours of storage (reneweconomy.com.au)

submitted 1 year ago by vividspecter@lemm.ee to c/australia@aussie.zone

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[-] Edgelord_Of_Tomorrow@lemmy.world 14 points 1 year ago* (last edited 1 year ago)

Check this out: https://raygen.com/projects/raygen-power-plant#resources

Batteries were a stopgap until we worked out something better. This plant gets 70% efficiency and more than enough energy storage by refrigerating a cold block, then using stored waste heat + the cold block to create a temperature differential, creating steam (in a closed loop, don't need a big water supply) to spin a turbine that generates power when the sun goes down. Absolutely genius, already deployed and operating and yet nobody is talking about it.

[-] IndefiniteBen@feddit.nl 4 points 1 year ago

What's the advantage of that solution over existing solutions like heating molten salts?

[-] Edgelord_Of_Tomorrow@lemmy.world 1 points 1 year ago

Efficiency. You're collecting 70% (potentially 80%) of the available energy. The best PV is below 30% and the best molten salts are 35% max.

[-] palitu@aussie.zone 1 points 1 year ago

I am listening to a The Solar Insiders Podcast, which is interviewing the CEO of RayGen (thanks for intoducing it to me, really cool).

the 70% is the efificency of the energy storage, which is similar to pumped hydro. ie, they put in 1MWh to the chiller, and will recover 0.7MWh from the organic rankin cycle turbine.

so, they get the 30% of the solar (or whatever it is), plus the recovery of the heat. They were saying that for 1 tower, they get 1MW of solar and 2MW of heat. but they never said how much of the 2MW of heat gets converted to electricity, or what the efficiency is, but it sounds like they need to consume electricity to use the ORC (ie for the chiller).

one other thing is that they ORCs can provide grid inertia which is a cool outcome too.

[-] Edgelord_Of_Tomorrow@lemmy.world 1 points 1 year ago* (last edited 1 year ago)

Hi mate, I think you misunderstood me.

It captures 30% of energy as PV and 60% as heat energy. The whole system itself is about 80% efficiency in terms of the energy captured from the sun, not the PV itself.

This makes it more effective than if you somehow had a molten salt and a normal PV plant in superposition on the same site.

[-] palitu@aussie.zone 1 points 1 year ago

i haven't been able to find the actual insolation to electricity efficiency anywhere. Do you have a link that shows the incoming energy to output electricity?