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barbazoo | on: Semi-transparent, colored cadmium telluride photovoltaic panels in agrivoltaics
> The USDA now expects 5.65 billion bushels of corn to be used for ethanol production in 2026-27

> The department has raised its corn production forecast by 234 million bushels to 16 billion bushels.

https://bioenergytimes.com/usda-raises-2026-27-us-corn-use-f...

About a third! Way more than I thought. I wonder how much of that would have to be covered in panels to get the same energy.

rossjudson | parent | next
I wonder if we are depleting the soil to create all that corn. I really don't understand how the lifecycle of soil works, and maybe it's time to go off and ask AI...
KaiserPro | root | parent
depends on how its done, but almost certainly yes.

soil is a living thing, and varies by location. Clay, loam, sandy, etc etc. Then there is a layer of fungus that forms filaments. The roots of the plants grow into this, and then the invertebrates move shit about creating voids and pockets of nutrients.

ploughing can be disruptive to this. but more likley pumping pesticides and herbicies, along with moving the water table causes it to die off leaving only part of the biome behind.

Basically think of it like your intestines. You can live with a "clean"[1] gut, but you'll have the shits constantly, which'll make you dry and windy. Same with soil.

[1] think post antibiotic.

idiotsecant | parent | next
you don't even want to aim for the same energy. With pure solar you need to aim for about 4x nominal output in order to approximately match the utility of something that meets that nominal output at essentially any time like, for example, a natural gas plant. We make about 1.2 giga-gallons of ethanol per year [1] (phew quite a unit, there). A gallon of ethanol has something like 76k BTU/gallon[2]. When we burn Ethanol in an ICE we can usefully extract about 25% of it's energy into rotation. That leaves us with about 5.5 kwH of useful energy per gallon of ethanol. If my orders of magnitude aren't wrong that's something like 6.6 twH which isn't that crazy, considering last year the US make something like 300twH in utility scale solar output. so maybe an additional 25% addition to our solar production.

[1] https://www.eia.gov/petroleum/ethanolcapacity/ [2] https://afdc.energy.gov/files/u/publication/fuel_comparison_...

lantry | parent
The article I linked claims 3.2%, which seems incredibly low, but maybe ethanol production is really just that inefficient.