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Great! I hope we do make big investments in renewable sources of electricity. But this article glosses over two biggish issues: - we can’t rely on intermitten

Great! I hope we do make big investments in renewable sources of electricity. But this article glosses over two biggish issues: - we can’t rely on intermittent power source without grid scale batteries (which we don’t cheaply have) - fossil fuel land use is exaggerated since it is double counted (e.g. you might drill for oil on a farmed field) and since it can be cheap, remote land. Solar land use is usually single purpose and near the users (so typically more expensive/useful land).

scotth 5y ago
Can livestock live under solar installations?
- chris1993 5y ago
  It seems quite possible if they fix the issue of having panels too close to the ground. https://www.abc.net.au/news/rural/2020-08-25/parkes-solar-panel-sheep-trial-early-positive-results/12581756 https://www.abc.net.au/news/rural/2020-08-25/parkes-solar-pa...
- jagger27 5y ago
  I'm sure some would appreciate the shade. Most "free-range" chickens actually live in big enclosed warehouses so they might appreciate some fresh air under solar panels. Grazing animals probably wouldn't work very well.
- sp332 5y ago
  No, growing plants out in the sun is much more efficient than capturing the light with a solar panel and then growing the plants elsewhere.
  - nerdponx 5y ago
    But growing plants in arid sunny regions requires a lot of irrigation, which might offset the benefits of maximizing solar efficiency.
    - sp332 5y ago
      The question was about places you would raise livestock.
  - scotth 5y ago
    Could there be a balance? Some grasses grow with partial light. With the right inter-panel spacing, could it be that a grazing animal might require more space, but not to an unreasonable degree? (I assume there are other considerations for the pasture...ease of finding the animals, moving them around, etc)
    - scotth 5y ago
      And while I'm thinking about it (and I'm way out of my depth here), but sunlight is a lot more powerful than growlights, is it not? Could power be siphoned to an extent, to supplement growth?
      - scotth 5y ago
        I'm realizing that the loss in the system means this wouldn't make sense. Better to use existing light.
  - Xt-6 5y ago
    Installing solar panel above fields to boost the production of both is a thing. https://en.wikipedia.org/wiki/Agrivoltaic https://en.wikipedia.org/wiki/Agrivoltaic
  - samatman 5y ago
    Believe it or not, one of the problems deserts have for growing plants is too much sun. Or rather, too much sun for available water. Installing solar panels high enough that goats don't bump into them, and planting shade-tolerant arid plants, can absolutely support grazing.
- Xt-6 5y ago
  Goats/sheeps are often used to clean the weeds in solar farms https://solargrazing.org/what-is-solar-grazing/ https://solargrazing.org/what-is-solar-grazing/ There are also studies that show that solar panel above fields can help boost production of both: solar panel get cooled by the plant perspiration and the plant get cooled by the shade of the panel.
  - guerrilla 5y ago
    > For the safety of the existing, low-mount solar arrays, goats, cows, pigs, and horses are not recommended. Goats climb anything.
bjt 5y ago
I don't think the "usual" patterns of solar will hold in the future. The article's example of a solar farm in the Australian outback, with undersea cables running to Singapore, pretty dramatically undercuts your second point.
- vitus 5y ago
  I was surprised to hear that's economical. Singapore to Darwin is about 2000 miles. For reference, that's comparable to Chicago to LA. That's at least an order of magnitude larger than what I'm used to thinking about for transmission. It turns out that if you want to drive your transmission loss down, you need to run at (substantially) higher voltage. This is predominantly driven by resistive loss because your transmission wires aren't perfect conductors, as well as corona loss which scales with voltage. https://web.archive.org/web/20110604181007/https://www.aep.com/about/transmission/docs/transmission-facts.pdf https://web.archive.org/web/20110604181007/https://www.aep.c... has some stats on stats on line losses. At 765 kV (this is 50x what you'd see on a local transmission line), with the best cited figure (circa 2007) of 0.5% loss per 100 miles, you'd see about 10% loss over 2k miles. That's not great, but it doesn't actually seem horrible -- if you're producing 2x the power you need anyways, then you're still delivering a huge surplus.
  - wumpus 5y ago
    China has recent laid a bunch of very long high-voltage DC cables to transport power west to east. None of them are underwater, but it sure seems possible. https://en.wikipedia.org/wiki/List_of_HVDC_projects#Asia https://en.wikipedia.org/wiki/List_of_HVDC_projects#Asia -- and sort by length.
    - akvadrako 5y ago
      It's certainly interesting, especially their 1100 kV lines. But what matters is cost; China is building a lot of new coal capacity so it's not like renewables + HVDC is a slam dunk.
    - vitus 5y ago
jeffbee 5y ago
It sounds like you have a somewhat fanciful idea of what fossil fuel production means. Usually it means 5-10 acres get scraped flat. PV isn't going to take anywhere near the amount of land that has been wrecked for oil, gas, and coal. https://www.google.com/maps/@28.4198071,-98.8400976,792a,35y,189.53h/data=!3m1!1e3 https://www.google.com/maps/@28.4198071,-98.8400976,792a,35y...
stewbrew 5y ago
You can put solar panels on roofs, above highways or farmland. You can even put them into windows. But I agree that single use solar power plants are probably more efficient. Your first point seems to be an actual but manageable problem though.
Jedd 5y ago
TFA wasn't really trying to address those issues. And in the case of: > - we can’t rely on intermittent power source without grid scale batteries (which we don’t cheaply have) .. for domestic users, behind the meter storage is fast becoming compelling. I had (with local subsidies) AUD $7,000 worth of panels installed earlier this year, and generate an average of 2.5 more power than I consume. A $10,000 battery system probably cover my domestic usage for all but the most rare run of cloudy days. That second figure's on a downward trend, too, especially as flow storage and other battery technologies start to benefit from the scale-up.
- sesuximo 5y ago
  I made this point because (I thought) TFA was saying all we need is better government policies, but we also need cheap storage and long distance transmission (which are hard/expensive). Your example shows that the storage cost is still on the order of the cost of panel installation, and you live in a very sunny place so probably use the battery less than average (I’m guessing based on AUD).
  - Jedd 5y ago
    Well, here in AU we definitely need better government policies - as our current administration is hellbent on coal and gas, and penalising renewables. As per the story linked in TFA, written by two former AU prime ministers, the reasons for this aren't hard to identify. Depending on panel capacity and storage size, then yeah, you may find they align - but it's all a tradeoff. My point with those numbers is that for a reasonably small cost (compared to say the capex of a house build, which is the time these things should be installed) you can get very close to self-reliance in terms of electricity, at least at a residential scale, so we're not all held up by grid-scale storage systems. Commercial consumers of electricity tend to have predictable cycles, and therefore their baseload is much easier to manage.

scotth 5y ago

Can livestock live under solar installations?

chris1993 5y ago
It seems quite possible if they fix the issue of having panels too close to the ground. https://www.abc.net.au/news/rural/2020-08-25/parkes-solar-panel-sheep-trial-early-positive-results/12581756 https://www.abc.net.au/news/rural/2020-08-25/parkes-solar-pa...
jagger27 5y ago
I'm sure some would appreciate the shade. Most "free-range" chickens actually live in big enclosed warehouses so they might appreciate some fresh air under solar panels. Grazing animals probably wouldn't work very well.
sp332 5y ago
No, growing plants out in the sun is much more efficient than capturing the light with a solar panel and then growing the plants elsewhere.
- nerdponx 5y ago
  But growing plants in arid sunny regions requires a lot of irrigation, which might offset the benefits of maximizing solar efficiency.
  - sp332 5y ago
    The question was about places you would raise livestock.
- scotth 5y ago
  Could there be a balance? Some grasses grow with partial light. With the right inter-panel spacing, could it be that a grazing animal might require more space, but not to an unreasonable degree? (I assume there are other considerations for the pasture...ease of finding the animals, moving them around, etc)
  - scotth 5y ago
    And while I'm thinking about it (and I'm way out of my depth here), but sunlight is a lot more powerful than growlights, is it not? Could power be siphoned to an extent, to supplement growth?
    - scotth 5y ago
      I'm realizing that the loss in the system means this wouldn't make sense. Better to use existing light.
- Xt-6 5y ago
  Installing solar panel above fields to boost the production of both is a thing. https://en.wikipedia.org/wiki/Agrivoltaic https://en.wikipedia.org/wiki/Agrivoltaic
- samatman 5y ago
  Believe it or not, one of the problems deserts have for growing plants is too much sun. Or rather, too much sun for available water. Installing solar panels high enough that goats don't bump into them, and planting shade-tolerant arid plants, can absolutely support grazing.
Xt-6 5y ago
Goats/sheeps are often used to clean the weeds in solar farms https://solargrazing.org/what-is-solar-grazing/ https://solargrazing.org/what-is-solar-grazing/ There are also studies that show that solar panel above fields can help boost production of both: solar panel get cooled by the plant perspiration and the plant get cooled by the shade of the panel.
- guerrilla 5y ago
  > For the safety of the existing, low-mount solar arrays, goats, cows, pigs, and horses are not recommended. Goats climb anything.

bjt 5y ago

I don't think the "usual" patterns of solar will hold in the future. The article's example of a solar farm in the Australian outback, with undersea cables running to Singapore, pretty dramatically undercuts your second point.

vitus 5y ago
I was surprised to hear that's economical. Singapore to Darwin is about 2000 miles. For reference, that's comparable to Chicago to LA. That's at least an order of magnitude larger than what I'm used to thinking about for transmission. It turns out that if you want to drive your transmission loss down, you need to run at (substantially) higher voltage. This is predominantly driven by resistive loss because your transmission wires aren't perfect conductors, as well as corona loss which scales with voltage. https://web.archive.org/web/20110604181007/https://www.aep.com/about/transmission/docs/transmission-facts.pdf https://web.archive.org/web/20110604181007/https://www.aep.c... has some stats on stats on line losses. At 765 kV (this is 50x what you'd see on a local transmission line), with the best cited figure (circa 2007) of 0.5% loss per 100 miles, you'd see about 10% loss over 2k miles. That's not great, but it doesn't actually seem horrible -- if you're producing 2x the power you need anyways, then you're still delivering a huge surplus.
- wumpus 5y ago
  China has recent laid a bunch of very long high-voltage DC cables to transport power west to east. None of them are underwater, but it sure seems possible. https://en.wikipedia.org/wiki/List_of_HVDC_projects#Asia https://en.wikipedia.org/wiki/List_of_HVDC_projects#Asia -- and sort by length.
  - akvadrako 5y ago
    It's certainly interesting, especially their 1100 kV lines. But what matters is cost; China is building a lot of new coal capacity so it's not like renewables + HVDC is a slam dunk.
  - vitus 5y ago

jeffbee 5y ago

It sounds like you have a somewhat fanciful idea of what fossil fuel production means. Usually it means 5-10 acres get scraped flat. PV isn't going to take anywhere near the amount of land that has been wrecked for oil, gas, and coal. https://www.google.com/maps/@28.4198071,-98.8400976,792a,35y,189.53h/data=!3m1!1e3 https://www.google.com/maps/@28.4198071,-98.8400976,792a,35y...

stewbrew 5y ago

You can put solar panels on roofs, above highways or farmland. You can even put them into windows. But I agree that single use solar power plants are probably more efficient. Your first point seems to be an actual but manageable problem though.

Jedd 5y ago

TFA wasn't really trying to address those issues. And in the case of: > - we can’t rely on intermittent power source without grid scale batteries (which we don’t cheaply have) .. for domestic users, behind the meter storage is fast becoming compelling. I had (with local subsidies) AUD $7,000 worth of panels installed earlier this year, and generate an average of 2.5 more power than I consume. A $10,000 battery system probably cover my domestic usage for all but the most rare run of cloudy days. That second figure's on a downward trend, too, especially as flow storage and other battery technologies start to benefit from the scale-up.

sesuximo 5y ago
I made this point because (I thought) TFA was saying all we need is better government policies, but we also need cheap storage and long distance transmission (which are hard/expensive). Your example shows that the storage cost is still on the order of the cost of panel installation, and you live in a very sunny place so probably use the battery less than average (I’m guessing based on AUD).
- Jedd 5y ago
  Well, here in AU we definitely need better government policies - as our current administration is hellbent on coal and gas, and penalising renewables. As per the story linked in TFA, written by two former AU prime ministers, the reasons for this aren't hard to identify. Depending on panel capacity and storage size, then yeah, you may find they align - but it's all a tradeoff. My point with those numbers is that for a reasonably small cost (compared to say the capex of a house build, which is the time these things should be installed) you can get very close to self-reliance in terms of electricity, at least at a residential scale, so we're not all held up by grid-scale storage systems. Commercial consumers of electricity tend to have predictable cycles, and therefore their baseload is much easier to manage.