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Land near energy demand is not scarce almost anywhere. Where "near" means "Within 1000km". And it doesn't need to be near. Transmission lines are cheap and h

by mapt 2y ago

Land near energy demand is not scarce almost anywhere. Where "near" means "Within 1000km". And it doesn't need to be near. Transmission lines are cheap and highly efficient infrastructure if you have a sensible process of land tenure (whether via routinized/generous eminent domain, Harberger Taxation, or other means). Moving electricity is among the cheapest, most efficient industrial processes that exist. *With all due respect to the Maldives, Gaza, Hong Kong, et cetera

grumpy-de-sre 2y ago
And don't be sleeping on the potential of UHVDC transmission.
- mapt 2y ago
  This is like the potential of High-Speed Rail. It isn't a theoretical, it's something China is 30+ completed projects deep on. The technology existed decades ago. We just treat infrastructure like it's an impossibility here. https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity_transmission_in_China https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity...
  - closewith 2y ago
    What you and the GP are discussing are fundamentally different solutions to agrivoltaics. One is inherently decentralised (not only decentralised power generation, but also local nitrogen fixing and reduced water demand) and the other is Just A Better Grid™. Just A Better Grid™ is inherently valuable, but it's not a substitute nor is it in competetion with agrivoltaics.
  - grumpy-de-sre 2y ago
    Was in Northern China recently, Got to say the shiny and non-rusted transmission pylons in Hebei got me more excited than was probably warranted. I don't think I've seen a shiny pylon before, I guess we mostly just stopped building them decades ago. On the topic of agriculture I was very impressed by all the polytunnels we spotted from the high speed rail heading north out of Beijing. Every valley, and nook and cranny was full of them. Took a couple photos of a small town in inner Mongolia that we passed, was amazing seeing green crops in the middle of a Siberian winter. I believe this was a farm using recycled water to grow cut flowers https://imgur.com/a/kw1IDZ3 https://imgur.com/a/kw1IDZ3
    - ZeroGravitas 2y ago
      I think those might be a specific kind of greenhouse rather than a standard polytunnel. The back wall is essentially a solar heat store. Here's an article on them: Chinese-style Solar Greenhouses https://ag.purdue.edu/department/btny/ppdl/potw-dept-folder/2022/chinese-style-greenhouse.html https://ag.purdue.edu/department/btny/ppdl/potw-dept-folder/...
      - mapt 2y ago
        Yeah, this highly optimized passive solar design is one of those things that seems very obvious when energy is too expensive to waste on international transportation or excessive heating in a cold climate. Citrus production in 40 below zero. By pursuing artificially inexpensive energy we are doubling down on a great number of wasteful practices that are largely avoidable.
      - grumpy-de-sre 2y ago
        Thank you! That's exactly what they are. Even "higher" tech than I first anticipated.
closewith 2y ago
To realise the benefits of local generation, near means on the order of 1,000m, not km.
- mapt 2y ago
  What benefits?
  - closewith 2y ago
    Decentralisation and low capital cost, the points made in the article.
    - mapt 2y ago
      Real estate cost (the opportunity cost of human occupancy) is capital cost. So is the material and labor for any of the more elaborate frame systems required to work on a non-flat surface. Only about half of Africa has any home access to electricity, and very few have access to the sort of high current associated with HVAC or EVs. Much of the population are going to leapfrog over the phase of full expansive grid construction, access & maintenance, and go directly to a somewhat more decentralized mode of operation. But that experience isn't all that relevant to the developed world, whose countries have invested tens of thousands of dollars per person in establishing almost universal electrical grids.
      - closewith 2y ago
        I think you should read the thread you are replying to again.
- dgacmu 2y ago
  This depends too much on the specific grid topology to be generally true. For example, there is an underground transmission line that is one of the bottlenecks for about 30,000 people in my part of Pittsburgh. It's not too uncommon to have summertime glitches or outages due to overload on that one circuit. Any generation installed on the consumer side of that line helps - and that's several km. There's a planned solar project on an old partially reclaimed slag heap that will add generation proximal to that line, for example. (It's land that is too polluted for just about any other use, which is a fantastic place to stick some utility scale solar while still staying within the boundary of the city.)
wongarsu 2y ago
At least in Europe, building transmission lines is a much longer process than building solar. Partially because of the complexity of acquiring land from a large number of owners, but more importantly because of NIMBYs that do everything to oppose new transmission lines that might disrupt the landscape. And some of the NIMBYs own the land you need to build the transmission line. Building a 1000km high capacity transmission line is a multi-decade project in this part of the world

by mapt 2y ago

grumpy-de-sre 2y ago

And don't be sleeping on the potential of UHVDC transmission.

mapt 2y ago
This is like the potential of High-Speed Rail. It isn't a theoretical, it's something China is 30+ completed projects deep on. The technology existed decades ago. We just treat infrastructure like it's an impossibility here. https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity_transmission_in_China https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity...
- closewith 2y ago
  What you and the GP are discussing are fundamentally different solutions to agrivoltaics. One is inherently decentralised (not only decentralised power generation, but also local nitrogen fixing and reduced water demand) and the other is Just A Better Grid™. Just A Better Grid™ is inherently valuable, but it's not a substitute nor is it in competetion with agrivoltaics.
- grumpy-de-sre 2y ago
  Was in Northern China recently, Got to say the shiny and non-rusted transmission pylons in Hebei got me more excited than was probably warranted. I don't think I've seen a shiny pylon before, I guess we mostly just stopped building them decades ago. On the topic of agriculture I was very impressed by all the polytunnels we spotted from the high speed rail heading north out of Beijing. Every valley, and nook and cranny was full of them. Took a couple photos of a small town in inner Mongolia that we passed, was amazing seeing green crops in the middle of a Siberian winter. I believe this was a farm using recycled water to grow cut flowers https://imgur.com/a/kw1IDZ3 https://imgur.com/a/kw1IDZ3
  - ZeroGravitas 2y ago
    I think those might be a specific kind of greenhouse rather than a standard polytunnel. The back wall is essentially a solar heat store. Here's an article on them: Chinese-style Solar Greenhouses https://ag.purdue.edu/department/btny/ppdl/potw-dept-folder/2022/chinese-style-greenhouse.html https://ag.purdue.edu/department/btny/ppdl/potw-dept-folder/...
    - mapt 2y ago
      Yeah, this highly optimized passive solar design is one of those things that seems very obvious when energy is too expensive to waste on international transportation or excessive heating in a cold climate. Citrus production in 40 below zero. By pursuing artificially inexpensive energy we are doubling down on a great number of wasteful practices that are largely avoidable.
    - grumpy-de-sre 2y ago
      Thank you! That's exactly what they are. Even "higher" tech than I first anticipated.

closewith 2y ago

To realise the benefits of local generation, near means on the order of 1,000m, not km.

mapt 2y ago
What benefits?
- closewith 2y ago
  Decentralisation and low capital cost, the points made in the article.
  - mapt 2y ago
    Real estate cost (the opportunity cost of human occupancy) is capital cost. So is the material and labor for any of the more elaborate frame systems required to work on a non-flat surface. Only about half of Africa has any home access to electricity, and very few have access to the sort of high current associated with HVAC or EVs. Much of the population are going to leapfrog over the phase of full expansive grid construction, access & maintenance, and go directly to a somewhat more decentralized mode of operation. But that experience isn't all that relevant to the developed world, whose countries have invested tens of thousands of dollars per person in establishing almost universal electrical grids.
    - closewith 2y ago
      I think you should read the thread you are replying to again.
dgacmu 2y ago
This depends too much on the specific grid topology to be generally true. For example, there is an underground transmission line that is one of the bottlenecks for about 30,000 people in my part of Pittsburgh. It's not too uncommon to have summertime glitches or outages due to overload on that one circuit. Any generation installed on the consumer side of that line helps - and that's several km. There's a planned solar project on an old partially reclaimed slag heap that will add generation proximal to that line, for example. (It's land that is too polluted for just about any other use, which is a fantastic place to stick some utility scale solar while still staying within the boundary of the city.)

wongarsu 2y ago

At least in Europe, building transmission lines is a much longer process than building solar. Partially because of the complexity of acquiring land from a large number of owners, but more importantly because of NIMBYs that do everything to oppose new transmission lines that might disrupt the landscape. And some of the NIMBYs own the land you need to build the transmission line. Building a 1000km high capacity transmission line is a multi-decade project in this part of the world