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Comment by _aavaa_ | Hacker News Reader

It’s worth noting that the dichotomy you set up isn’t quite right. The land use for solar and wind isn’t an exclusionary zone. The area around a wind turbine can be used same as before (most often as farmland) without a negative impact on its productivity.

And the same is true for solar. In fact, a growing number of agro-voltaic projects are seeing a net positive on crop yields from solar panels due to the increased shading and decreased temperatures.

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This reminded me of a solar project at a US airport [0]. They placed solar panels to make a covered parking lot. I think it was part of a larger plan to use panels for cover and/or over some of the vast spaces that the airport covers

"Austin-Bergstrom International Airport (AUS) and Austin Energy celebrate the completion of a new solar panel array constructed on the AUS campus that will produce 1.8 megawatts of locally-generated, renewable energy. ... With 6,642 solar panels spanning across a distance that is equal size to two football fields, the array on the top floor of the airport’s Blue Garage is the largest on-site renewable energy installation on the AUS campus. The panels offer shaded parking for Blue Garage customers and will generate enough solar energy to power up to 160 homes per year."

[0] https://www.austintexas.gov/news/austin-bergstrom-internatio...

I was thinking of you set the solar up high, to create a diet of canopy, then you might be able to grow a rain forest under it which doesn't like direct sunlight and would allow animal habitat...?

Is it possible for solar panels to be semi-transparent so crops can still thrive underneath?

Yes it is: https://www.pv-magazine.com/2021/07/02/transparent-solar-pan...

“Combining two usage modes based on Insolight’s optical micro-tracking technology, these modules focus light on high-efficiency solar cells,” Insolight said in a press release. “When aligned, the optical system can generate energy (E-MODE), but it is also possible to unalign it to ‘leak’ the light (MLT-MODE). The solar modules therefore act like a ‘smart’ shade adjusting the amount of light they let through.”

This makes it possible to optimize the photosynthesis of plants during the seasons and reduce the negative impact of high summer heat on the yields and quality of agricultural products, while recovering the rest of the light in the form of electricity. Starting from July, the panels will be tested for four years on a 165-square-meter surface area. They will replace protective plastic tunnels on strawberries and raspberries.

“Dynamically adjusting the light transmitted to the plants paves the way for increased protection from climate variations and possible increases in crop yields thanks to the matching of the light to the needs of the plants and the lowering of the temperature during heat waves via the shading effect,” said Bastien Christ, head of the berries and medicinal plants group at Agroscope.

A similar project using different module technology: https://www.pv-magazine.com/2023/10/31/baywa-re-starts-build...

That's not needed, just have gaps between the panels so they provide partial shade. Many food crops can't tolerate "full sun" well, and will grow perfectly fine even with partial illumination.

The logistics of trying to plant, maintain and harvest crops underneath a bunch of solar panels while also needing to deal with the subsequent issues of uneven runoff of water from rain make it seem impractical. Just cover parking lots, malls and supermarkets with them, we have plenty of those, and they're closer to where the electricity is needed than agricultural land.

We absolutely should cover those, but there is a lot of farmland. There may not be enough "mall-land"

Well, when i see solar panels atop every mall and commercial building, when every home has a solar roof, then i'll entertain chopping down wilderness or sacrificing farmland to the cause. I still see plent of bare rooftop to address first.

Well good job it's not your decision to make then.

If the economic benefits of adding solar to their farm outweighs the costs then farmers will start adding them to farms.

Literally nobody proposes "sacrificing" farmland.

I'm looking at a legal agreement on my desk to lease 120 acres of productive eastern Nebraska farmland to build a commercial scale solar project. The land would be taken out of production ("sacrificed") for the 50 year lease, with payments about twice what the land leases for for agriculture (soybeans).

It is very common. Farming is hard, margins slim at best. And farmers are given great leeway in how they may make money from land. Regulation is lax. Many fields have been turned from the production of food to the production of electricity, while countless factory rooftops sit covered only in tar and asphalt.

As soon as we stop using farmland to grow energy crops when the same area could give us 20x the energy using solar panels.

The home roofs are going to be done off the more expensive solar installations ($/kW) that we can build because they’re so small.

It’s also fascinating how quickly the Nirvana fallacy shows up when it’s time to talk about renewables. Supposedly chopping down forests for solar (which isn’t the main way of getting land) or the farmers choosing to put something on their land is top of mind. But chop those forests to make something else, or have the farmers grow super subsidized corn and there isn’t a peep.

You can make up whatever you like, saying "seems". Facts are better.

The fact is that agrivoltaics has been very successful, for reasons you probably would not guess in a wholesale void of facts. Looking up the facts, you could actually learn something.

Regardless of your opinion on this subject, agrivoltaics projects are being installed today at an increasing rate, and they’re going well, from what I’ve read. It’s not some theoretical proposal, it’s happening now. It’s likely that solar panels will be installed both in parking lots and over farmland.

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