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sfzombie13 t1_iu8lvdk wrote

pv - photovoltaic. took way longer than i care to admit, and saw the title of the publication, to figure that out.

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ChiralWolf t1_iu8ru4r wrote

Terrible article. Basically just comes down to "different locations will be apply to implement solar more efficiently by using different techniques".

Even for the spacing their findings are actually "between 4.83 and 7.34 meters" which isn't huge difference. Depending on the panel size a 7 meter gap could easily hold an entire additional panel.

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trollsmurf t1_iu8thz9 wrote

Or use passive heat pipes with heat sinks.

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Robert2737 t1_iu97q6u wrote

Can u grow crops between panels?

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bkubicek t1_iu9g8ss wrote

One would gain nearly the same by increasing the thermal emissivity of the gront glass by a plastic coating. Howrver, it would weather soonish and might develop browning. Or by adding plastic cooling ribs on the backside, no need for metal since the bottleneck is the air transition, not the material conduction.

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bradleykent t1_iu9rasw wrote

You gotta keep ‘em separated.

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Glittering_Cow945 t1_iu9rka9 wrote

Well, only if the space the cells are on is extremely cheap conpared to the cells themselves..

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Miserable-Expert-119 t1_iu9z0av wrote

Yes. There are a few articles scatted about the internet on this subject. There seems to be success with crops growing in areas that would be normally too hot and sunny. Pilot testing shows crops like strawberries do well. Irrigation can be cut back a bit has evaporation is a bit less. The tricky bit would be mechanizing this kind of agriculture without having to design new machines that can work between the rows and under the panels. Doable but may need work. However, if one owned a house with a decent yard it would make more sense to install a panel array in your garden. For instance your roof is not likely to be at both the optimum angle or direction for the sun. In your garden the mounts can be set at the optimum angle and optimum direction. Panels are cheaper to install on the ground than on a roof. Panels run cooler on the ground so you get that extra 1 or 2 % of power. You can clean the panels yourself by squeegeeing instead of hiring somebody to go up on the roof.

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screwhammer t1_iua4gk3 wrote

You can, but you're gonna have to put tiny humans instead of wide machines to harvest them, you're gonna have to design some special irrigation that won't damage the panels, and you're gonna have to account for people occasionallt banging with sharp tools against glass or cutting cables.

That's gotta be some expensive crop to maintain.

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Grimij t1_iua6m1a wrote

If you need to increase the spacing by 500% to improve LCOE by ~2% that's dumb, I'm sorry.

I come from Ag Land California, planting crops between solar rows simply isn't feasible. You need a very dry and clean panels for them to be effective and efficient, but with the amount of moisture, dirt, corrosive fertilizer, and herbicide/pesticide sprays makes the absolute worst environment to put solar.

Building lean-to shelters for pumps, equipment, or overall packing with solar is great, though.

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Knowssomething t1_iub8umv wrote

I suppose it depends on whether space or number of panels is your limiting factor. Hypothetically if you had a hill to build a solar farm on you could cover it in solar panels. But you might have a whole hill and 500 panels so in that case the spacing could play a much bigger factor.

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adrianmonk t1_iubm1a3 wrote

>If you need to increase the spacing by 500% to improve LCOE by ~2% that's dumb, I'm sorry.

That's not what the study says, is it? At least not according to the way I read the article.

It seems like there is a trade-off between the cost of land and the energy output, and their analysis tells you where the sweet spot is in the middle. From the article:

> Through the modeling, the group ascertained that the optimal levelized cost of energy (LCOE) point was $0.29/kWh, with row spacing varying between 4.83 and 7.34 meters. With two-meter spacing, the LCOE was $0.33/kWh, and with 11 meters it was $0.36/kWh.

Note that very close spacing (2m) and very wide spacing (11m) are both worse than intermediate spacing (4.83-7.34m).

They mentioned agriculture, but I don't think their analysis takes that into account. I think it's just a perk that they're throwing out there as a conceivable side benefit of wider spacing.

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danbln t1_iucghng wrote

In my experience it works well with organically grown perennial crops that benefit from noon shade(many berries do for example). And also for grazing, especially by sheep as they don't tend to mess with the panels.

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Desktopaccount13a t1_iucgzkm wrote

LCOE.

Latent Cost of Equity

Latest Cuarterly Operating Earnings.

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Lordfate t1_iucjcpc wrote

Two whole percent! And surely the increased spacing was less than two percent?

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RedditorsArGrb t1_iucn0cb wrote

This is a brief summary of some NREL research linked in the article that anyone really interested in the details can go read.

>Depending on the panel size a 7 meter gap could easily hold an entire additional panel.

Doesn't really matter if that erases your profit margin. It's niche techno-economic research to improve cost modeling efforts, you don't need to have some incisive perspective on the subject or complain that the studied effects aren't big enough to interest you.

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RebelWithoutAClue t1_iucp037 wrote

You probably make a bigger improvement in what the back panel receives with bifacing panels if you open up the spacing than you get in lower operating temp.

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dalitpidated t1_iud216q wrote

As temperature decreases, voltage increases, increasing the overall wattage. Its quite dramatic, a system at 150F will operate at 240V and at -20F will rise to 600V. As far as predicting airflow in various outdoor conditions? Sounds like the Science guys were running tests on the mushrooms again. You could probably net better results in manufacturing ground mounted panels to better vent the air they ate in contact with. The Building Codes make it difficult to engineer practical passive cooling on roof mounted systems.

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