4 ms·

Where are you getting 10 square miles of solar farm to support 1 square mile of dense indoor farming? Energy can be stored or brought in from other areas durin

Where are you getting 10 square miles of solar farm to support 1 square mile of dense indoor farming? Energy can be stored or brought in from other areas during the night. And no you can't stack in a greenhouse for the same reason that there are hardly any plants growing on the jungle floor. This sort of thing is already being done in London and Sweden. It's the level of automation that is making this news. Of course it starts at the high end but eventually all food will be grown like this just because it'll be the most efficient overall. You focus entirely on the efficiency of photosynthesis in plants when there are so many other variables as for why this is a good idea.

Retric 11y ago
Running these for decorative lettuce in a big city is one thing, when farmers use this for corn in Iowa you might have a point. Shipping bulk rice from US to China is cheaper in terms of energy than shipping electricity required to grow that same Rice. PS: Another sanity check. The US has 922 Million Acres of farmland. At 1kw/m * 8h / day that's vastly more than the world total energy usage. You can't even replace that with fusion power as the waste energy would directly produce significant global worming. (4046 sq M / Acre * 8kwh/day = 32 Megawatt hours per Acre * .92 billion = 30,000 Twh per day, world electricity is under 30,000Twh per year. ) https://en.wikipedia.org/wiki/World_energy_consumption#/media/File:World_energy_consumption.svg https://en.wikipedia.org/wiki/World_energy_consumption#/medi...
- lhopki01 11y ago
  Grains will be the last thing to change and that won't be for a very long time. Also you have to take into account increased yields, faster grow times, lower fertiliser, pesticide, herbicide and tractor fuel costs. Your sanity check is way off. Solar panels only get about 22W/m^2 though out the year on average and they're more efficient than plants. Second the maximum plants can use is about 100W/m^2 and that is at maximum midday strength. Now lets take into account varying intensity of sunlight, growing seasons, leaf orientation, gaps between plants and other factors and your energy requirements are much lower. Research is still being done but most plants grow very well with the full red spectrum and 10-20% of the blue spectrum. This vastly reduces the energy required.
  - Retric 11y ago
    22W/m^2 is either really out of date or your thinking far north. If you really want more farmland and have a lot of energy there are simply much better options, desalination and irrigation of west Texas for example. PS: You can bump plant efficiency from 10 to 20% from using a narrow frequency of light, but that's a fairly low cap. And 10%(plant) > {20%(panel) * 20%(plant) =} 4%, which is why I said you need to have 50% panels to 'break even'.

Retric 11y ago

Running these for decorative lettuce in a big city is one thing, when farmers use this for corn in Iowa you might have a point. Shipping bulk rice from US to China is cheaper in terms of energy than shipping electricity required to grow that same Rice. PS: Another sanity check. The US has 922 Million Acres of farmland. At 1kw/m * 8h / day that's vastly more than the world total energy usage. You can't even replace that with fusion power as the waste energy would directly produce significant global worming. (4046 sq M / Acre * 8kwh/day = 32 Megawatt hours per Acre * .92 billion = 30,000 Twh per day, world electricity is under 30,000Twh per year. ) https://en.wikipedia.org/wiki/World_energy_consumption#/media/File:World_energy_consumption.svg https://en.wikipedia.org/wiki/World_energy_consumption#/medi...

lhopki01 11y ago
Grains will be the last thing to change and that won't be for a very long time. Also you have to take into account increased yields, faster grow times, lower fertiliser, pesticide, herbicide and tractor fuel costs. Your sanity check is way off. Solar panels only get about 22W/m^2 though out the year on average and they're more efficient than plants. Second the maximum plants can use is about 100W/m^2 and that is at maximum midday strength. Now lets take into account varying intensity of sunlight, growing seasons, leaf orientation, gaps between plants and other factors and your energy requirements are much lower. Research is still being done but most plants grow very well with the full red spectrum and 10-20% of the blue spectrum. This vastly reduces the energy required.
- Retric 11y ago
  22W/m^2 is either really out of date or your thinking far north. If you really want more farmland and have a lot of energy there are simply much better options, desalination and irrigation of west Texas for example. PS: You can bump plant efficiency from 10 to 20% from using a narrow frequency of light, but that's a fairly low cap. And 10%(plant) > {20%(panel) * 20%(plant) =} 4%, which is why I said you need to have 50% panels to 'break even'.