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Comment by aaronbrethorst | Hacker News Reader

The most remarkable details about solar panels I've heard recently came from the environmentalist Bill McKibben[1] on a podcast[2]:

I was standing in a cornfield in Illinois this time last summer, with a farmer who grew corn for ethanol and was converting much of his fields to solar arrays. He said, I can grow in this acre, and he pointed to an acre in a good farmerly way, he said, in this acre, I can grow enough ethanol to run my Ford F-150 pickup, most beloved vehicle in the American iconography. It’ll run 25,000 miles off the ethanol I can grow on an acre in a year. If I cover that same acre with solar panels, then I can produce enough electrons to run my Ford F-150 Lightning, the EV version of the same truck, I can run that not 25,000 miles, but 700,000 miles.

[1] https://en.wikipedia.org/wiki/Bill_McKibben

[2] https://www.msnbc.com/msnbc-podcast/why-is-this-happening/di...

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Not to mention that the cornfield has to be essentially torn down and rebuilt every year, while the panels will just sit there quietly working for at least 20 years with very little maintenance.

The figures are, if anything, an underestimate.

An acre of solar is about 350-450,000 kWh/year. An F-150 Lightning does 2 miles per kWh. So that's about right.

One acre of corn makes about 400 gallons of bioethanol. Even the newest F-150s do an atrocious 18 mpg in real usage, so you need nearly 1500 gallons to go 25,000 miles. So this figure is presumably ignoring the non-ethanol content of the fuel, which is most of it.

Bingo. Fermenting (up to) 200 bushels is also a point source for significant CO2. Though you get 1.5t of material for animal feed.

A regular ICE fuel system will make it 700,000 miles but the battery won’t.

So the eqivalent solar energy is 700 000 miles… a year?

Wow, that's astounding. Thanks.

Yea, but it says more about how bad corn biofuels are than how good solar is. Also, Iowa is too far north for solar to do much good in the fight against AGW. If you want solar, move to Mexico (or even New Mexico) where it actually makes environmental sense.

Generating solar power in Mexico won't keep Iowans from warming their homes with natural gas and powering their F-150s with petroleum, so solar panels in Iowa are needed for the fight against AGW.

The problem is that more energy is required and more CO2 produced in making the panels than they replace during their use. So in Iowa, using solar actually increases CO2 production, not decreases it. Somehow you are missing that.

Solar's EROEI is only 4. So anywhere with a solar albino of less than .25 means solar there does more harm than good. NASA Goddard provides a map of where that is. From memory, I believe Iowa's is about .22. The breakeven line roughly goes through San Francisco.

No, all of that is false. Some of it was true at one point, but it has been false for decades. There is no such thing as "solar albino". I would think it was easy to find the correct information. Where are you getting this false information?

It would obviously be better in terms of per-panel efficiencies to be further south, but solar is still effective much further north than 40N. Nearly all of Europe from Madrid northward is higher latitude than that. And since Iowa has people there, the costs and losses of getting energy from Mexico to Iowa may outweigh much of the advantages for quite some time.

Assuming solar isn't displaced by something else, one day we'll presumably see highly insolated areas exporting power over huge interconnects, but for now, fitting a panel basically anywhere is still better than not fitting it at all.

> Also, Iowa is too far north for solar to do much good in the fight against AGW.

Absolutely not, Iowa is great for solar, it often provides more income than corn (and corn has massive subsidies), and is certainly better than most of Europe. Iowa really is not very far north

https://globalsolaratlas.info/map?c=44.374588,-77.81811,3

It's true that the available solar resource is smaller in Iowa than in New Mexico, but the ratio is only about 2:3. https://solargis.com/resources/free-maps-and-gis-data?locali...

It also ignores the reason why corn biofuels exist, because we subsidize corn production for national security reasons and there's a ton of extra produced so they try and find profitable uses for it.

We sell it on the international market to keep worldwide food prices down.

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