Turning a solar power system into its own backup (arstechnica.com)

51 pointsby PaulHoule2 days ago19 comments

bob1029 11 hours ago

We can break the 5500K temperature limit with passive elements and some clever engineering.

https://en.wikipedia.org/wiki/Solar-pumped_laser

https://ieeexplore.ieee.org/document/1553831

michaelscott 12 hours ago

Maybe I missed it somewhere in the write up but in what way is the solar system its own backup? It seemed like the battery was just subbed for a combustion system using stored heat?

ThrowawayTestr 10 hours ago

It's a weird way to phrase it. It's a solar generator that shares it's turbines with a conventional generator.

conorcleary 8 hours ago

I was picturing a solar-charged battery running a light above the panel overnight

PaulDavisThe1st 5 hours ago

Not quite. It's a solar thermal (heat generator) that feeds a heat storage facility via an air-flow heat exchanger. That exchanger can alternatively be fed hot air generated using any other technology, including burning fossil fuels.

So, the heat storage facility is "source neutral". In addition, precisely how the stored heat is used "downstream" is also not a central part of the design, but turbines etc. are a likely option.

mattmaroon 9 hours ago

In the way that that will make you click the link.

ulkhf 11 hours ago

How is this different from Ivanpah?

cyberax 9 hours ago

I guess that they're using multiple smaller towers? This does reduce the complexity of the tracking and alignment systems.

downrightmike 12 hours ago

REAL TLDR: Just Slap some gas generators onto the bad design and it'll work this time(tm)

cowfire 12 hours ago

TLDR: it's a concentrated solar plant (field of mirrors shine light on a tower to boil water) with a backup system that boils the water by burning stuff.

fhdkweig 12 hours ago

"The first installation will be"

It also hasn't been built yet. Let me know when they have one working prototype. Until then, it is just a concept on a drawing board.

ozyschmozy 12 hours ago

If I understand the article correctly, there is no boiling water, it uses hot air only. It says the concentrated solar generates air up to nearly 1000 degrees, and that's used to heat up compressed air to run through a turbine, with the eziting air at around 250 degrees. Burning fuel would replace the initial source of hot air. Burning fossil fuels to get hot air and then dumping 250 degree air to the environment doesn't seem very efficient, but the article doesn't mention anything about the efficiency of the process with either source.

Does say the hot air at the end can be used for industrial processes, so it might not be completely lost

PaulDavisThe1st 5 hours ago

Not quite right.

The 1000 degree air is not used directly to drive turbines, but instead to deliver heat to a heat storage unit via a heat exchanger. The solar-heated air, after flowing through the heat exchanger, is still around 250 degrees and the article mentions some possible uses of that heated air (again, not generation).

Generation occurs using heat coming from the heat storage unit, not using the solar-heated hot air. Since the heat storage unit can also be fed by hot air heated via other means, this makes the heat storage unit "source neutral" - it can be heated by solar or fossil fuel combustion (or whatever).

The turbines are "downstream" of the heat storage unit.

bombcar 8 hours ago

Advanced new power generation technique!

Look inside, it’s boiling water to spin turbines.

PaulDavisThe1st 5 hours ago

There's actually no mention of the technology used by the turbines. This article is about how you heat up a heat storage facility that is then used (somehow) to drive turbines. Might be water, might not be.

Razengan 2 hours ago

Have we discovered any way to directly generate a stream of electrons without any mechanical movement?

alex43578 2 hours ago

Solar panels

Razengan an hour ago

doh

I'm dumb, but I meant, anything else and similarly magical?

I guess there's the ATP stuff used by all lifeforms..

chickenbig an hour ago

> to boil water

Brayton cycle so no water needed. It seems as if the concept has not changed since https://www.rostinternational.com/wp-content/uploads/2019/10...