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>Although, desert solar farms are a very bad idea... As an ignorant doofus, care to explain why? Sticking solar panels in otherwise empty land seems like a goo

>Although, desert solar farms are a very bad idea... As an ignorant doofus, care to explain why? Sticking solar panels in otherwise empty land seems like a good idea.

dx034 4y ago
Maybe because of the ecosystem? Although it doesn't seem to be too invasive if you can even grow crops under solar panels.
ncmncm 4y ago
They get very, very hot, so their conversion efficiency falls sometimes as low as 12%. They also get dusty, which can cut conversion by as much as 80% again unless you dust frequently. And, getting so hot, their useful lifetime is reduced to as little as 20 years. Float them on a reservoir instead, and conversion efficiency is improved to as much as 23%, lifetime increased to... nobody knows yet. Evaporation is reduced. Biofouling underneath is reduced. Some wildlife prefers the shade, under. Turtles like to climb up on the edge. And, cleaning is easy. (Search: "floatovoltaics") Float them on a canal, likewise; the evaporation and biofouling reductions are extra important there. California estimates they could generate 12 GW on its canals, and prevent millions of gallons of evaporation loss every year. Stand bifacial (double-sided) panels in fencerows on cropland, running north-south, far enough apart to drive a tractor and stuff between. They pick up morning and evening sun, while protecting crops from heat stress and cutting evaporation. Some crops yield more, few less. When you have plenty of crop land, you don't need them to pick up every last bit of sun; you have plenty of room, so they can be spread out. You could grow berries or cherry tomatoes under, whatever else you grow. They don't get so hot in fields, either, and the vertical mounting keeps dust off. And they produce revenue year-round. (Search: agrivoltaics) They also do well in pasture, where the livestock keep the weeds down. On some crops, you want them horizontal above the plants to protect from freak hailstorms, heavy downpour, and harsh noonday sun. We all like parking under solar panels in parking lots, where they keep the rain off on our way to the car, and keep it from getting too hot inside. And, they make roofs last longer; not just on houses, but on warehouses, factories, airport terminals, malls, what have you. Finally, deserts are usually a long way from where people want the power. There is absolutely no shortage of places to put solar panels where they will work better and longer, and do other good besides.
- wkearney99 4y ago
  As someone that's owned boats for many years I'd have to wonder about the problems of marine growth and putting anything IN canal waters. Over the space, sure, but floating? And then there's also the 'keeping them clean' question, I'd wonder what the cleaning trade-offs would be for 'erected over' vs 'floating in' installations?
  - ncmncm 4y ago
    The go-to for floating solar in the US is Healdsburg reservoir. Marine growth on the float is OK; I think the panel itself is held up out of the water. I guess a worry could be about heavy things attaching and eventually sinking it, requiring that the carrier be replaced. At least some canals need to remain "navigable", which needs the panels in a frame overhead. I think this is being done in India. The last number I encountered was that there was 3GW of floating solar known installed worldwide, much of it in southeast Asia, e.g. Singapore.

>Although, desert solar farms are a very bad idea... As an ignorant doofus, care to explain why? Sticking solar panels in otherwise empty land seems like a good idea.

dx034 4y ago

Maybe because of the ecosystem? Although it doesn't seem to be too invasive if you can even grow crops under solar panels.

ncmncm 4y ago

They get very, very hot, so their conversion efficiency falls sometimes as low as 12%. They also get dusty, which can cut conversion by as much as 80% again unless you dust frequently. And, getting so hot, their useful lifetime is reduced to as little as 20 years. Float them on a reservoir instead, and conversion efficiency is improved to as much as 23%, lifetime increased to... nobody knows yet. Evaporation is reduced. Biofouling underneath is reduced. Some wildlife prefers the shade, under. Turtles like to climb up on the edge. And, cleaning is easy. (Search: "floatovoltaics") Float them on a canal, likewise; the evaporation and biofouling reductions are extra important there. California estimates they could generate 12 GW on its canals, and prevent millions of gallons of evaporation loss every year. Stand bifacial (double-sided) panels in fencerows on cropland, running north-south, far enough apart to drive a tractor and stuff between. They pick up morning and evening sun, while protecting crops from heat stress and cutting evaporation. Some crops yield more, few less. When you have plenty of crop land, you don't need them to pick up every last bit of sun; you have plenty of room, so they can be spread out. You could grow berries or cherry tomatoes under, whatever else you grow. They don't get so hot in fields, either, and the vertical mounting keeps dust off. And they produce revenue year-round. (Search: agrivoltaics) They also do well in pasture, where the livestock keep the weeds down. On some crops, you want them horizontal above the plants to protect from freak hailstorms, heavy downpour, and harsh noonday sun. We all like parking under solar panels in parking lots, where they keep the rain off on our way to the car, and keep it from getting too hot inside. And, they make roofs last longer; not just on houses, but on warehouses, factories, airport terminals, malls, what have you. Finally, deserts are usually a long way from where people want the power. There is absolutely no shortage of places to put solar panels where they will work better and longer, and do other good besides.

wkearney99 4y ago
As someone that's owned boats for many years I'd have to wonder about the problems of marine growth and putting anything IN canal waters. Over the space, sure, but floating? And then there's also the 'keeping them clean' question, I'd wonder what the cleaning trade-offs would be for 'erected over' vs 'floating in' installations?
- ncmncm 4y ago
  The go-to for floating solar in the US is Healdsburg reservoir. Marine growth on the float is OK; I think the panel itself is held up out of the water. I guess a worry could be about heavy things attaching and eventually sinking it, requiring that the carrier be replaced. At least some canals need to remain "navigable", which needs the panels in a frame overhead. I think this is being done in India. The last number I encountered was that there was 3GW of floating solar known installed worldwide, much of it in southeast Asia, e.g. Singapore.