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Solar panels open crop lands to farming energy

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Re: Solar panels open crop lands to farming energy

#61

Post by mytailorisrich »

jahnu wrote: post #60
mytailorisrich wrote: post #59

Earlier quoted context omitted.

That's the issue isn't it? I simply wrote that the root cause of our problems is the population level. You replied that I implied the most monstrous policies. And now not only you try to deflect but you ask ME to come up with a counter argument... F that.

You are misinterpreting my words. I can assure you I have no intention to imply that you personally are suggesting monstrous policies. I am saying that once we learn certain details and facts all that we all are left with that can change population levels are monstrous policies. I hope the difference is clearer now. To be as clear as possible: I'm presenting an argument with facts that you or any other reader here ma…

You should stop digging...

Bye.

Re: Solar panels open crop lands to farming energy

#62

Post by rstuart4133 »

moloch-hai wrote: post #55
maxerickson wrote: post #22

Earlier quoted context omitted.

I wonder how often interspersing the panels with crops ends up being better than packing the panels onto the most marginal portion of the land parcel. There's often ridges or whatever to deal with on a field.

There is a hell of a lot of ag land, so you only need to site solar where conditions are ideal. E.g. in hill country, just on southern slopes. But any farm has marginal parts hard to harvest that could take dense paneling. Much of the appeal of agrivoltaics is its continuous steady income supplementing harvest peaks, reducing debt load. England is just now panicking over farmers removing fields from farm production t…

Yes, the article does create the impression the amount of solar we can have is limited by the land it consumes.

100e18 joules = the amount of energy the USA consumes in a year. [0]

4,000 sq kilometres = area of solar panels to generate the energy. [1]

5,000,000 sq kilometres = USA land devoted to agriculture. [2]

Ergo whatever is the problem is with 100% solar, it isn't the availability of land. Even doing bizarre things like saying we will over provision by a factor of 10 doesn't stress the land supply. (Over provisioning by a factor of 10 gets rid of the cloudy day problem, because even on the cloudiest day you get 10% yield).

If you put solar on ag land, you will do it because the solar helps the ag, not because solar needs the land.

The cost of those solar panels might have something to do with it not happening. At $1.00/watt it's about USA$800B. It's less than the USA spent on the Iraq war. But it's significant nonetheless, and you need storage. So perhaps double it.

[0] USA Energy consumption, all types (not just electricity) https://www.eia.gov/energyexplained/us-energy-facts/

[1] 4,000 sq kilometres = (64km x 64km) assuming 4 peak hours of solar per day and 20% efficiency. That's 2,500 sq miles = (50mi x 50mi).

[2] https://www.ers.usda.gov/data-products/ag-and-food-statistic...

Re: Solar panels open crop lands to farming energy

#63

Post by moloch-hai »

rstuart4133 wrote: post #62
moloch-hai wrote: post #55

Earlier quoted context omitted.

There is a hell of a lot of ag land, so you only need to site solar where conditions are ideal. E.g. in hill country, just on southern slopes. But any farm has marginal parts hard to harvest that could take dense paneling. Much of the appeal of agrivoltaics is its continuous steady income supplementing harvest peaks, reducing debt load. England is just now panicking over farmers removing fields from farm production t…

Yes, the article does create the impression the amount of solar we can have is limited by the land it consumes. 100e18 joules = the amount of energy the USA consumes in a year. [0] 4,000 sq kilometres = area of solar panels to generate the energy. [1] 5,000,000 sq kilometres = USA land devoted to agriculture. [2] Ergo whatever is the problem is with 100% solar, it isn't the availability of land. Even doing bizarre th…

> If you put solar on ag land, you will do it because the solar helps the ag

Or helps the farmer's cash flow. They might put in solar where it is not technically ideal, but helps them personally.

Panels are under $0.50/W peak lately, and still falling. Of course mounting costs money, but most farmers have experience with putting up fences. Wiring, maybe less.

To the degree that electricity can displace fuel fed to heat engines, the need is reduced by the inefficiency of the heat engine. So solar replaces 2.5x coal-fired electricity, 5x automotive vs. gasoline, 3-5x domestic heating (when outside temp is high enough a heat pump works) vs NG, oil, or propane, depending on chimney losses. Electrolysing water for hydrogen for steel processsing is lossy, while burning coal for heat is less so, so maybe 0.5x there.

When aviation finally goes to LH2, it will be complicated. Flight deck will be higher, H2 turbines may be more a bit efficient than for kerosene, and lofting an LH2 fuel load takes much less energy than lofting a kerosene load; but again, electrolysing is lossy.

So assuming an average advantage of 2x, and cost-per at half cited, that's only $200B spread over decades. Iraq cost >$5T.

Re: Solar panels open crop lands to farming energy

#64

Post by giantg2 »

sitkack wrote: post #57
giantg2 wrote: post #16

Earlier quoted context omitted.

For many varieties, you want the dew to evaporation of the plant in the morning. It reduces the risk of fungal diseases.

But it sounds being able to control light/heat/moisture with panels can be beneficial, the mixture is site and crop specific.

The article doesn't mention being able to control those things though.

Re: Solar panels open crop lands to farming energy

#65

Post by jahnu »

ranit wrote: post #41
jahnu wrote: post #13

> There is no unused arable land on a planet that’s already struggling to support a human population that cleared 8 billion last month The amount of this land that is dedicated to growing food for livestock and the livestock themselves is simply astounding. Reducing meat consumption is a much simpler solution and I believe the one that will win out anyway. Complicated solar systems like this will only become relevant…

> Even precision fermentation is an easier to implement fix for land use, which looks increasingly like it can reduce our need for land to grow grains. See Solar Foods for example What do you refer as "precision fermentation" here? The linked Wikipedia article is about "growing microbial biomass that can be used as edible protein". Just curious, perhaps I missed the connection.

My understanding was that was the umbrella term for various technologies one of which Solar Foods use.

https://www.monbiot.com/2022/11/26/fermenting-a-revolution/

Is it incorrect?

Re: Solar panels open crop lands to farming energy

#66

Post by ranit »

jahnu wrote: post #65
ranit wrote: post #41

Earlier quoted context omitted.

> Even precision fermentation is an easier to implement fix for land use, which looks increasingly like it can reduce our need for land to grow grains. See Solar Foods for example What do you refer as "precision fermentation" here? The linked Wikipedia article is about "growing microbial biomass that can be used as edible protein". Just curious, perhaps I missed the connection.

My understanding was that was the umbrella term for various technologies one of which Solar Foods use. https://www.monbiot.com/2022/11/26/fermenting-a-revolution/ Is it incorrect?

Thanks for the link, good to learn more. Perhaps you are right. Mine was a genuine, layman question.

Re: Solar panels open crop lands to farming energy

#67

Post by moloch-hai »

giantg2 wrote: post #64
sitkack wrote: post #57

Earlier quoted context omitted.

But it sounds being able to control light/heat/moisture with panels can be beneficial, the mixture is site and crop specific.

The article doesn't mention being able to control those things though.

> This article promotes false assumptions.

Re: Solar panels open crop lands to farming energy

#68

Post by jahnu »

ranit wrote: post #66
jahnu wrote: post #65

Earlier quoted context omitted.

My understanding was that was the umbrella term for various technologies one of which Solar Foods use. https://www.monbiot.com/2022/11/26/fermenting-a-revolution/ Is it incorrect?

Thanks for the link, good to learn more. Perhaps you are right. Mine was a genuine, layman question.

No worries! I’m no expert either :)
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