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Comment by maxk42 | Hacker News Reader

It would be a lot more expensive to put them on warehouses than the millions of acres of unused land nearby. But the mountain west also has ice and hail and solar panels tend not to live up to their expected lifetimes out here.

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But there's another consideration: albedo (reflectance of the earth's surface). If the warehouse roofs already tend to be dark-colored, solar panels wouldn't reduce the area's albedo as much as covering light-colored ground (like sand).

I saw an assertion somewhere that if we put enough solar panels in the desert to meet all of our energy needs, the net decrease in the earth's albedo would cause as much warming as the burning of equivalent fossil fuels.

A search brings up this article (not necessarily the one I'm remembering, but interesting): https://theconversation.com/solar-panels-in-sahara-could-boo...

Solar panel albedo isn’t as bad as it first appears because they’re converting significant energy into electricity. In terms of local heat a panel that reflects 10% of the suns energy and coverts 22% into electricity is similar to a surface that reflects 32% of the suns energy.

The net effect means solar panels end up roughly similar to grasslands and between typical bare soil and desert sand or in terms of effective albedo.

Yeah but that energy as electricity produces work... which produces waste heat. You end up with the same amount of heat as you do an equally black surface just getting hot.

There's no escaping it, but fortunately all that heat gets radiated into space already on the dark side keeping the heat capture at net neutral, once the thermal reserve increases from decreased albedo of course.

“In terms of >local heat<“

That electricity isn’t producing heat where the panels are, it’s potentially in some laptop on the other side of the planet.

The actual energy released by the worlds electricity converted into waste heat isn’t currently meaningful on a global scale. But, assuming it keeps increasing placing floating solar panels over the ocean actually reflects more energy back into space. That would have a net cooling effect even including the electricity produced.

But the living creatures in the ocean need the light, cyanobacteria and phytoplankton are keystone species for the main oceanic biome.

We were talking about paneling unused dark patches on land.

Modern warehouse roofs like a home depot or something are mostly all white or light colored to reduce air conditioning costs.

I guess because that's cheap enough, because I can only recall ever seeing one big-box type of store (HD, Target, Walmart, Supermarket, etc.) where the corrugated roof was insulated in any way whatsoever.

The sands here are black, my friend.

We need to start getting in the habit of building large awning's over parking lots, especially with a more extreme future. Mixing electric charging stations, it'll be trivially cheap to also tack on some solar panels.

This and also making all new commercial construction require load rating for 80% panel coverage is just sensible planning.

What are the environment effects of that?

Somewhere south of the environment effects of building tens of thousands of warehouses.

Don‘t you think the environmental impact of having both warehouses and separate solar fields is certainly higher than having warehouses with solar panels?

Not that I'm advocating for warehouses, but I'm not positive that's actually the case. Warehouses can use vertical space much more efficiently than solar panels.

I met a environmental biologist (it was some similar sounding job) who does environmental impact studies for solar farms in the desert. He said lots of stuff gets displaced or killed when they install the panels. There’s no way to avoid it. It definitely stresses the environment.

The biological soil crust in much of the Western U.S. is easily trampled (a single footprint can do it), and takes years to regenerate: https://en.m.wikipedia.org/wiki/Biological_soil_crust

I live by BLM (open public) land of this kind, and you can definitely see the change in flora growing on a given patch of land for several years after it has been disturbed.

It may look barren, but the desert West is host to all kinds of critters: multiple species of ants, beetles of all kinds, lizards, horny toads, quail, rabbits, bobcats, ravens, hawks, owls, bees, wasps, butterflies, snakes, etc. etc. Why not put the panels on the warehouses where the land is already disturbed?

To your point, it can be avoided by not doing it at all. But you’re definitely 100% going to screw up the environment by installing panels on unspoiled land.

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