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In reply to the discussion: Just have a think [View all]

NNadir

(37,196 posts)
2. One should definitely have a think, particularly at what is being overlooked and minimized.
Thu Sep 10, 2020, 03:59 PM
Sep 2020

He is correct that perovskites have been investigated seriously as a solar panel material for over ten years. The pace of perovskite publications is accelerating, quite a bit.

The "only" 20 mg/watt nonsense about lead is extremely misleading and requires a critical thinking response, because, well, it's dangerous.

As of the 2019 edition of the World Energy Outlook, the world was using just about 600 exajoules of energy per year. The solar industry generally regards it's half a century old failure - complete failure - to address climate change despite the expenditure of trillion dollar quantities of money by using "percent talk," in which they point to the percent growth in solar output from a trivial output to a still trivial amount of energy produced. But let's embrace "percent" talk for the hell of it, and assume that this noxious technology reaches 10% of the world energy supply, that would be 60 exajoules.

California, which is on fire because solar energy and all the other "renewables will save us" hoopla didn't work to address climate change, is one of those rare places where - for a portion of the day - solar energy can provide a considerable percentage of generated electricity for a period of the day. Here is the CAISO line graph for so called "renewable energy" production in California recorded last night at 7:30 PDT.



If one looks into this - I spent much of the day checking in on it, and it was very clear that yesterday was a low wind day and the "massive" solar output was mostly solar during the daylight hours.

By evening, at pretty much the same time, the so called "renewable energy" profile looked like this:



Inspection of the first graphic indicates that the "peak" operating hours for solar energy - which dominated "renewable energy" yesterday as the wind was not available, lasted from about 9 in the morning until 5 in the afternoon (which was well before demand peaked in California). This means that solar energy was available for about 8 to 10 hours if we add an hour on each end for the ramp up. We are near the equinox, so we can leave out the effect of what it would look like in winter, but not get the benefit of the summer solstice.

So to get "10%" - something half a century of cheering for solar has never come close to achieving - we would actually need to generate 180 exajoules = 60/.3 since 8 hours is roughly a third of a day.

There are 31,557,600 seconds in a sideral year. This means the average continuous power requirement for solar would be 180 exajoules/31,557,600 seconds = 1.9 TerraWatts of power, 1.9 trillion watts. At 20 mg/watt, this translates into about 38,000 tons of lead, distributed widely in low concentrations. The low concentrations of course, have an impact on all of the handwaving that goes on about "recycling."

Lead has a half life in human flesh on the order of decades. If you are poisoned by lead - and let's be clear - we are going to have poor people manufacture this stuff and the waste from the manufacturing plant, and the waste at landfills.

And it will end up in landfills:

The reality is that because of low value as a recycled material, and the extensive energy requirements of transport and recycling, these cells will end up in landfills as toxic electronic waste, something that is already taking place even though the solar industry is trivial. We will then more or less be distributing lead continuously, basically until it runs out. And we are going to be placing it among people who are not educated in anyway with respect to hazardous materials.

Then of course, we have the wiring, inverters, and battery chemistry with which to deal which is another wholly ignored topic in this presentation.

Saying "it's not as bad as car batteries" is like announcing that having breast cancer is not so bad because pancreatic cancer kills you faster than breast cancer.

Finally, the most efficient solar perovskites are cesium iodine bridged hexaiodoplumbate solar cells. Neither cesium nor iodine are readily abundant elements. There is a lot of talk about tin bromide analogues, but they are far less efficient.

This guy is reasonably bright, and his simplified discussion was cute as far as it went, but it's more of the vague "rah! rah!" we've been hearing for half a century about solar "breakthroughs" with no result. Since we've begun throwing billions of dollars per year at the solar industry - sometimes close to a hundred of billions of dollars in a year - climate change has actually been accelerating, not decelerating. We have reached the unprecedented rate of 2.4 ppm/year for new accumulations of the dangerous fossil fuel waste carbon dioxide in the planetary atmosphere.

The "solar will save us" conceit didn't work; it isn't working and it won't work. The reason is physics.

The presentation beyond the surface is rather glib, which one could tell by having that awful person Elon Musk handing out his usual Trump scale lies.

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