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Comment by fbnbr | Hacker News Reader

This just becomes interesting if electricity can be produced from reflected photons by the moon such as at night energy production is possible. Other than that I believe in fusion although the giant fusion reactor does help during the day. Instead of making photovoltaic more efficient they should do this with batteries

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I believe we will build a functional net energy gain fusion reactor probably in the next decade if things go well (I’m rooting for SPARC), but we will still need to build an actual power plant (designed for long life, serviceability, improve efficiency based on what was learned before) and that will take a while. And then we need to build lots of them. And they will be very expensive.

Probably fusion power will not be cheaper than renewables inside of 50 years, because fusion power plants will simply be very expensive.

In the next 20 years we need to decarbonize as much as possible. Fusion sadly won’t have much of an impact for that.

But in 30 years when todays new renewables are at the end of their service life, we have an opportunity to replace them with fusion. That said, renewables will be that much cheaper in 30 years. I think for a while fusion will make the most sense for large industrial manufacturing operations that necessarily require large constant amounts of power.

> (I’m rooting for SPARC)

Gives a whole new meaning to "Sun Microsystems"

Even if fusion was widely available and affordable you will still want other sources of power for peak demand. Like fission nuclear reactors, they will be good for base power-load. Fusion reactors won't be able to spin up and down based on demand willy nilly.

Given most demand is during the day and early evening solar is a good complement, but the more mixed renewals you have in your grid the better it will tolerate shocks in supply and demand.

> This just becomes interesting if electricity can be produced from reflected photons by the moon such as at night energy production is possible

"referring to thermal energy grid storage (TEGS) consisting of a low-cost, grid-scale energy storage technology that uses TPVs to convert heat to electricity above 2,000 C"

You all speak in miracles here, the use case seems to be converting thermal energy and energy storage. Why the moon, and what does that have to do with regular photovoltaic efficiency?

> Why the moon, and what does that have to do with regular photovoltaic efficiency?

Presumably to produce energy at night and avoid the need for storage. Seems like a moonshot, though.

But not with these cells? Not getting it :( Or why does (any) storage thing become only interesting then?

They, like me, read the title as "Photovoltaic", which are solar cells. And the comment was around that presumably. I was also reading the headline and the first comments entirely confused until I read the article and it elaborate that these are "ThermoPhotoVoltaic" cells, which involves heat and ties in to the article's comments about this being used for energy storage.

All around, confusing. I didn't even know we had such a thing.

Moonlight is ~1 mW/m^2, so good luck with that.

I was thinking you could cover the moon in rotating mirrors to redirect the light to solar panels. And if they can be controlled independently, you can tweak them and basically use the surface of the moon as a giant display, who wouldn't want the moon to look like a giant Apple logo?

The moon also ends up in shadow about half the time.

Just becomes interesting? I don't really know how to parse that. What is it if electricity can't be produced that way?

It's a total waste of time to use moonlight. It is a million times dimmer than sunlight.

Are you aware the the light reflected from moon to earth compare to direct sunlight is probably more than 4 or 5 order of magnitudes smaller?

This excludes any possibility for generating reasonable amounts of energy from moon light. There is a reason why it is much colder during the night.

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