http://i.stack.imgur.com/6kuZf.png

Blue LEDs are much more efficient than most other colours and having three sets of voltage control or three seperate circuits is more expensive. Plus "single wavelength" is only even approximately true of a laser. Those spectra you linked to are still a fairly broad range (to the point where red and green can even be somewhat distinct under an orange LED even if both are very orange-ish).

Additionally your source describes a modern white LED

> The other method of creating white light is known as spectrum adjustment.

> Spectrum adjustment happens when light is absorbed and then re-emitted again. By doing so, the color and appearance of the light can be altered. There is a caveat, however, that the light can only be shifted to larger wavelengths. If a material were able to absorb a long wavelength of light and emit the same amount of a shorter wavelength, this would violate the conservation of energy. This is why it was not possible to generate blue light from other diodes. However, the reverse process does in fact work: if a blue diode is passed thorough a yellow phosphor, the blue and yellow combine into a white light well suited for everyday tasks.

RGB LEDs are at least three (and sometimes four) LEDs though.

This is because of the insane choice of blue light. Destroys your night vision so you can't see the darker parts.

LEDs are by no means monochromatic. And most use phosphors on a blue LED, not multiple LEDs.

All true. The general principle is neat and becomes more relevant as PV gets cheaper. Combine with a thermal store, feed the AC waste heat in too, and suddenly you've gotten rid of seasonal variability in temperate zones.

Couple things in the article make it sound a little sketchy though. If the PV module remains at 30C then how hot is the working fluid? Do they take out the below-bandgap energy before it hits the silicon or is the module hotter than the fluid?

Roof space hasn't really been limited until recently (price now makes it kinda viable). Separate solar thermal and PV have been a thing for a while now.

Working at a high enough temperature to make an efficient heat engine run would almost certainly make the PV performance worse or destroy it.

This will be low grade heat for space or water heating. Possibly applicable to chemic process or electrolysis too (heat can reduce the electricity needed to just splitting the molecule). Might be able to use the electricity to upgrade the heat using a heat pump for chemical use, although you're unlikely to beat a heliostat which is much simpler.

It hasn't happened to any significant degree yet. The tiny fraction that do exist have historically been recycled for metals and low grade glass at a loss or landfilled.

Recycling supply chains are being built and most of the world now has recycling mandates where manufacturers or importers need to have a plan in place before sale. The glass can be used circularly, silver and bismuth/lead are reusable. The silicon is downcycled to steel alloying or similar industrial use. There has been lab scale amorphous PV built from only decomissioned monocrystalline PV -- it worked but has not been commercialised.

Just as bad at understanding internet memes as relative scale of waste I see.

love the continuation of the parody of the bad faith concern trolling

you forgot the spongebob caps though.

> Never believe that anti-Semites are completely unaware of the absurdity of their replies. They know that their remarks are frivolous, open to challenge. But they are amusing themselves, for it is their adversary who is obliged to use words responsibly, since he believes in words. The anti-Semites have the right to play. They even like to play with discourse for, by giving ridiculous reasons, they discredit the seriousness of their interlocutors. They delight in acting in bad faith, since they seek not to persuade by sound argument but to intimidate and disconcert. If you press them too closely, they will abruptly fall silent, loftily indicating by some phrase that the time for argument is past.

Hey, just letting you know they're replacing coal plants with solar and wind like you asked.

More semantic games. Making a thing or agriculture isn't exponential growth. Neither is a bounded increase in consumption in only those places with poor quality of life. Straw men are also not relevant.

Have a read of your comments there and reflect on how disgusting and disingenuous they are.

Now you're trying to play semantic games by switching out the meaning of the word growth. Seems like the condescension was validated.

> Except much of what looks like an exponential is really an s-curve. We were never going to scale to infinite people, calories, land use, energy use, etc. We aren't going to build infinite solar panels.

Which is the degrowth premise... well done. You got there. Growth needs to end because it's physically impossible. And it needs to end soon because we're exactly where we were with the waste heat, land use and albedo decrease budget as we were with the CO2 budget when scientists started saying that maybe burning everything was a bad idea.

You've also switched back to talking about what sane countries do which is make and recycle monosilicon PV. The US industry is significant portion CdTe. You can't pretend that a monosilicon recycling industry is relevant.

Exponentials always beat polynomials.

Your premise that the technology solves it rather than delaying it by a couple of decades is faulty.

That said, the talking points are still wrong (except for the US industry which uses different materials and doesn't mandate recycling. It's comparatively tiny though, not even enough to meet a fraction of the local need).

They think they'll always be wearing the boot.

It's ambiguous then as to what cf they mean.

New western offshore wind is in the 40-50% cf range. EU solar is 13% so there's a big range there.

10TW net final energy to replace existing 18TW of world wide primary energy and cover some growth sounds pretty close to most ballparks so 30TW of 30% cf sounds reasonable.

30 * 8.760 is 260 not 26.

Net implying average output over the year. Ie. A 3.3kW nameplate tilting solar system in California is 1kW net. Primary energy is input, final energy is what is achieved. A 25% efficient gas engine running on tar sand oil with an EROI of 3 needs about 6kW of primary energy for 1kW of output. The 500GW or so of primary energy powering US transport can be replaced by 100GW of electricity. Similarly 200GW of gas heating can be 50GW of electric heat pump.

If the 30TW is nameplate then the capacity factor cancels some of the waste heat, so it's merely 10x what the US uses not 30x.

Even the locals are usually just responding to scare campaigns.

Order of magnitude error and a factor of 2-3 on topof that for work vs heat (if TW is net generation rather than peak). 30TW net is ten USAs of final energy, not one USA of primary energy.

We don't need scifi. Current tech is enough.

Scifi would be cool though.

Also 30TW of thermal generation is borderline in terms of sustainable waste heat levels.

Uruguay, Brazil (including one of their grids serving a largerpopulation than france being majority wind), and a fewother smaller nations.

Or unremediated uranium mines. Lowers the water use to keep from poisoning everything downwind too.

NIMBY is a stretch. More like Not In The Back Yard Of The Town I Was Paid To Crisis Act In.

It's called putting water on top of a hill and it's existed for millenia. It's not widespread because there isn't enough VRE or inflexible generation like nuclear to require it yet.