This was posted with the notion that the comment in black text on a white background is silly and unscientific, while the comment in white text on a black background is a rebuttal. However, both comments are a bit weird and lacking in nuance. In case I lose the image, here's what was said...
First person: "It's a bit cold outside this morning in middle America... Aren't you glad you aren't heating your home with a solar panel like nitwit Socialist @AOC is demanding?"
Second person: "Do Solar Panels work in the cold? YES! Solar Panels work by absorbing LIGHT from the sun, not heat. In fact, the chemical reactions that occur w/i the solar panels are more efficient at cooler temperatures. Also, white snow can act like a mirror to reflect MORE light onto them"
My friend: "The war on science"
So, the first comment seems to conflate rooftop solar with ground-based solar facilities. Most people don't have rooftop arrays on their houses, and people who heat their homes with electricity can get that electricity from anywhere on the grid. Also, AOC is a U.S. representative from New York's 14th district. She's not in "middle America" and attempting to mobilize "middle America" against a representative from another part of the country is just bullshit political drama, and has no bearing on the facts here.
The second comment does get one thing right. It is true that solar panels are more efficient at cooler temperatures. Solar panels work using the optical bandgap of semiconducting materials to excite electrons in their photovoltaic cells. For every material, the bandgap has a temperature coefficient. Material gets hotter, fewer electrons can cross the bandgap. Material gets colder, more electrons can cross the bandgap. So far, so good. But the materials selected for making PV cells in commercial solar arrays are selected, in part, because they're less sensitive to this effect.
We could make solar panels that would only worked in super-cold temperatures, but they wouldn't do us much good. Also, solar arrays use passive systems (and sometimes active systems) to keep panels cool. In some cases, those technologies falter in major heat waves, but ordinarily, they get the job done. I can assure you that if you're standing outside in the desert sun next to a working solar array, the insides of the panels are nowhere near as hot as the air around you. That's kind of the point.
Remember: solar panels need light. In severe winter weather, there's way less of it. Even a regular cloudy day can ruin the electricity yield of a solar facility. Snowstorms are worse still. Panels can become buried in snow or accumulate a layer of ice, either of which render them useless. Blizzards can also permanently damage these facilities, necessitating expensive repairs. When power providers know that a major snowstorm is coming in, they're not counting on solar facilities to keep the grid electrified, and for good reasons. It doesn't work that way. We're talking about some extreme cold here. -16 °F? That's -26 °C! If it's that cold, we can be sure that not a lot of sunlight is reaching the surface. I don't know if our second person in this exchange understands or remembers this fact, but light the light reaching the surface that causes solar panels to function is the very same light that causes the surface to warm up. Ergo, there ain't as much of it as normal. Ipso facto, solar panels are fucked in this situation. Q.E.D.
As for snow acting like a mirror and reflecting light onto solar panels, there are two major problems with that idea. Firstly, commerical solar panels are purpose-built to capture direct sunlight. They can absorb reflected light too, but there's a drop in efficiency there. Secondly, and more obviously, solar panels are at their most efficient when they're pointed at the sun. If they're tracking the sun properly (not a guarantee in winter storm conditions, by the way), then they're not going to be oriented to capture much reflected light.
It seems that almost everyone who saw this exchange interpreted the second comment as a strong takedown of the first one. In reality, both are pretty bad.
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