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They should just pave the mojave with solar panels. Nearly no one lives there and no one wants to live there and it is dead center to western states. If China

They should just pave the mojave with solar panels. Nearly no one lives there and no one wants to live there and it is dead center to western states. If China can pave mountains, a little desert with caliche should be easy

tjwebbnorfolk 1y ago
As a rule, if you're tempted to begin any sentence with "they should just..." -- don't. Electrical signal attenuation increases with the square of the distance, so you'll lose ~95% of the power to heat loss in the wires if you try to power Seattle from solar in Nevada -- not very eco-friendly, you'd agree? Also the extreme heat destroys solar panels. Also, dust. Also the permitting of stuff across state lines is so time-consuming it's effectively illegal. There are a lot of very good reasons why we haven't covered the desert in solar panels.
- Rebelgecko 1y ago
  Seattle is fine on power, you can pave the parts of the Mojave in California to power California instead (although tbh I think what we need most in CA is storage for when the sun goes down). I think you can also reduce heat loss by cranking the voltage up, right? I imagine that's how current interstate/cross-country power deals work
  - downrightmike 1y ago
    Bigger interstate wires hold more power and have a much higher thermal mass, which is fine until someone's tree shorts everything out because lines sag greatly with more heat/power
- amanaplanacanal 1y ago
  Seattle isn't a good example, as they have been carbon neutral since 2005. They have lots of hydro power in the Pacific Northwest.
- strongpigeon 1y ago
  > As a rule, if you're tempted to begin any sentence with "they should just..." -- don't. Strongly agreed. > Electrical signal attenuation increases with the square of the distance, so you'll lose ~95% of the power to heat loss in the wires if you try to power Seattle from solar in Nevada What? HVDC lines are usually estimated to have 3.5% power loss per 1000 km. Since power transmission is done using power lines, the inverse square law doesn't really apply here. > There are a lot of very good reasons why we haven't covered the desert in solar panels. That does remain true however. Cost concerns, grid access concerns, environmental concerns are all good reasons.
- agnokapathetic 1y ago
  > Electrical signal attenuation increases with the square of the distance not true. in standard HV-AC lines, power losses are ~10% per megameter. HVDC gets to 3-5%. So Nevada to Seattle would be at most 20% loss, and in practice 15%, and with HVDC closer to 7%. https://www.nationalgrid.com/sites/default/files/documents/13784-High%20Voltage%20Direct%20Current%20Electricity%20%E2%80%93%20technical%20information.pdf https://www.nationalgrid.com/sites/default/files/documents/1...
  - AnotherGoodName 1y ago
    I think the op must have been confused by the inverse square law for omnidirectional wireless transmission. https://en.wikipedia.org/wiki/Inverse-square_law https://en.wikipedia.org/wiki/Inverse-square_law This is where you picture an expanding wireless sphere of transmission from a point source and since the surface area of this sphere grows by the square of the distance you get this "power attenuates by the square of the distance" rule. This of course doesn't apply to power over a 2D cable.
  - kulahan 1y ago
    I have no dog in this fight, but this is so impressive it sounds wrong. I don’t think it is wrong, I’m just really blown away
    - yndoendo 1y ago
      "Taming the Sun: Innovations to Harness Solar Energy and Power the Planet" by Varun Sivaram [0] is a good source on ways to improve renewable energy from infrastructure design changes. He talks about the HVDC longitude runs that would improve transfer of electricity to areas that may be cloudy where it is sunny during peak. My point of view with Tesla vs Edison is that they were both right and wrong under select circumstances. [0] https://mitpress.mit.edu/9780262537070/taming-the-sun/ https://mitpress.mit.edu/9780262537070/taming-the-sun/
      - kulahan 1y ago
        Thanks, I’m looking forward to digging into this!
- deleted 1y ago
  [deleted]
- Aurornis 1y ago
  > Electrical signal attenuation increases with the square of the distance Power transmission lines at 60Hz primarily have ohmic losses, which are linear with length of the conductor. Interesting fact - Power transmission lines are long enough that the capacitive and inductive effects do matter a little bit, even though it's only 60Hz. That's why spacing between conductors is important. 3-phase lines will also rotate the order of conductors every so often to keep the average spacing between all pairs of lines similar.
  - vizzier 1y ago
    The mind boggles at how many little bits of information like this keep our world running smoothly...
- IncreasePosts 1y ago
  I think you're over estimating losses for high voltage transmission lines. It's "only" 800 miles from the Mojave to seattle. In China there is a high voltage transmission line over 2000 miles long
- derefr 1y ago
  I'll ignore your other points, because sibling comments are addressing them better. So here's something more unique: > Also the permitting of stuff across state lines is so time-consuming it's effectively illegal. This is true in general, but in this specific case, there are a lot of obvious ways to get around the problem, because Nevada is a moth-eaten shirt of federal land reservations — Nevada-the-political-entity only owns/regulates ~15% of the land of Nevada-the-geographic-territory. With the current state of the US federal government, lobbying to privately use one of those federal reservations would be a walk in the park; and once you're going "California -> federal land" instead of "Calfornia -> Nevada", regulation gets a lot simpler. Fun fact: there's a National Forest in Nye County (bordering California) that runs right up to the edge of the DoE-reserved area where they did the nuke tests. The feds are fine with running HVDC lines through National Forests (they're not Parks, after all), and "repurposing nuked ground for solar" is actually an easy-to-sell narrative at all levels. You could build solar there and backhaul it to California without ever touching land regulated by Nevada-the-political-entity.
- badc0ffee 1y ago
  Confidently, impressively wrong. Imagine how the power grid would work if there were 95% losses over 900 km.
dwedge 1y ago
Paving deserts with black heat absorbers that are only 10-20% efficient in converting that energy to electricity could well end up affecting climate more than burning coal would
- downrightmike 1y ago
  They're blue, and nothing about coal would be less impact. Coal starts with pulling down entire mountains to get to the coal. The whole process starts with environmental destruction and that's how it ends. The thermal mass of the panels is no where near significant. Especially compared to a run away greenhouse effect we know coal to cause.
  - dwedge 1y ago
    It's about the localised thermal effect in a desert https://www.westernsydney.edu.au/hie/stories/news_archive/solar_panels_sahara_climate_change https://www.westernsydney.edu.au/hie/stories/news_archive/so...
- glenstein 1y ago
  1% from a Dyson Sphere would be a better energy return than 100% efficiency from any conventional energy sorce. Similarly, 20% from solar is competitive with 60% from nuclear, 50% from coal, and is easily better than 100% from my neighbor Dan riding a bicycle powered electricity generator. You can't cite efficiency percentages in a vacuum to imply they are a better or worse than alternatives, because those aren't percentages of the same kinds of things, and they don't tell you about the economics, production in absolute terms or EROEI.
  - Ardon 1y ago
    The solar panels would overheat (and lose efficiency), since ~80% of the solar energy hitting it is absorbed as (mostly) heat. Generating solar energy in deserts is often done with a mirror based heating system for this reason.
    - 1y ago

tjwebbnorfolk 1y ago

As a rule, if you're tempted to begin any sentence with "they should just..." -- don't. Electrical signal attenuation increases with the square of the distance, so you'll lose ~95% of the power to heat loss in the wires if you try to power Seattle from solar in Nevada -- not very eco-friendly, you'd agree? Also the extreme heat destroys solar panels. Also, dust. Also the permitting of stuff across state lines is so time-consuming it's effectively illegal. There are a lot of very good reasons why we haven't covered the desert in solar panels.

Rebelgecko 1y ago
Seattle is fine on power, you can pave the parts of the Mojave in California to power California instead (although tbh I think what we need most in CA is storage for when the sun goes down). I think you can also reduce heat loss by cranking the voltage up, right? I imagine that's how current interstate/cross-country power deals work
- downrightmike 1y ago
  Bigger interstate wires hold more power and have a much higher thermal mass, which is fine until someone's tree shorts everything out because lines sag greatly with more heat/power
amanaplanacanal 1y ago
Seattle isn't a good example, as they have been carbon neutral since 2005. They have lots of hydro power in the Pacific Northwest.
strongpigeon 1y ago
> As a rule, if you're tempted to begin any sentence with "they should just..." -- don't. Strongly agreed. > Electrical signal attenuation increases with the square of the distance, so you'll lose ~95% of the power to heat loss in the wires if you try to power Seattle from solar in Nevada What? HVDC lines are usually estimated to have 3.5% power loss per 1000 km. Since power transmission is done using power lines, the inverse square law doesn't really apply here. > There are a lot of very good reasons why we haven't covered the desert in solar panels. That does remain true however. Cost concerns, grid access concerns, environmental concerns are all good reasons.
agnokapathetic 1y ago
> Electrical signal attenuation increases with the square of the distance not true. in standard HV-AC lines, power losses are ~10% per megameter. HVDC gets to 3-5%. So Nevada to Seattle would be at most 20% loss, and in practice 15%, and with HVDC closer to 7%. https://www.nationalgrid.com/sites/default/files/documents/13784-High%20Voltage%20Direct%20Current%20Electricity%20%E2%80%93%20technical%20information.pdf https://www.nationalgrid.com/sites/default/files/documents/1...
- AnotherGoodName 1y ago
  I think the op must have been confused by the inverse square law for omnidirectional wireless transmission. https://en.wikipedia.org/wiki/Inverse-square_law https://en.wikipedia.org/wiki/Inverse-square_law This is where you picture an expanding wireless sphere of transmission from a point source and since the surface area of this sphere grows by the square of the distance you get this "power attenuates by the square of the distance" rule. This of course doesn't apply to power over a 2D cable.
- kulahan 1y ago
  I have no dog in this fight, but this is so impressive it sounds wrong. I don’t think it is wrong, I’m just really blown away
  - yndoendo 1y ago
    "Taming the Sun: Innovations to Harness Solar Energy and Power the Planet" by Varun Sivaram [0] is a good source on ways to improve renewable energy from infrastructure design changes. He talks about the HVDC longitude runs that would improve transfer of electricity to areas that may be cloudy where it is sunny during peak. My point of view with Tesla vs Edison is that they were both right and wrong under select circumstances. [0] https://mitpress.mit.edu/9780262537070/taming-the-sun/ https://mitpress.mit.edu/9780262537070/taming-the-sun/
    - kulahan 1y ago
      Thanks, I’m looking forward to digging into this!
deleted 1y ago
[deleted]
Aurornis 1y ago
> Electrical signal attenuation increases with the square of the distance Power transmission lines at 60Hz primarily have ohmic losses, which are linear with length of the conductor. Interesting fact - Power transmission lines are long enough that the capacitive and inductive effects do matter a little bit, even though it's only 60Hz. That's why spacing between conductors is important. 3-phase lines will also rotate the order of conductors every so often to keep the average spacing between all pairs of lines similar.
- vizzier 1y ago
  The mind boggles at how many little bits of information like this keep our world running smoothly...
IncreasePosts 1y ago
I think you're over estimating losses for high voltage transmission lines. It's "only" 800 miles from the Mojave to seattle. In China there is a high voltage transmission line over 2000 miles long
derefr 1y ago
I'll ignore your other points, because sibling comments are addressing them better. So here's something more unique: > Also the permitting of stuff across state lines is so time-consuming it's effectively illegal. This is true in general, but in this specific case, there are a lot of obvious ways to get around the problem, because Nevada is a moth-eaten shirt of federal land reservations — Nevada-the-political-entity only owns/regulates ~15% of the land of Nevada-the-geographic-territory. With the current state of the US federal government, lobbying to privately use one of those federal reservations would be a walk in the park; and once you're going "California -> federal land" instead of "Calfornia -> Nevada", regulation gets a lot simpler. Fun fact: there's a National Forest in Nye County (bordering California) that runs right up to the edge of the DoE-reserved area where they did the nuke tests. The feds are fine with running HVDC lines through National Forests (they're not Parks, after all), and "repurposing nuked ground for solar" is actually an easy-to-sell narrative at all levels. You could build solar there and backhaul it to California without ever touching land regulated by Nevada-the-political-entity.
badc0ffee 1y ago
Confidently, impressively wrong. Imagine how the power grid would work if there were 95% losses over 900 km.

dwedge 1y ago

Paving deserts with black heat absorbers that are only 10-20% efficient in converting that energy to electricity could well end up affecting climate more than burning coal would

downrightmike 1y ago
They're blue, and nothing about coal would be less impact. Coal starts with pulling down entire mountains to get to the coal. The whole process starts with environmental destruction and that's how it ends. The thermal mass of the panels is no where near significant. Especially compared to a run away greenhouse effect we know coal to cause.
- dwedge 1y ago
  It's about the localised thermal effect in a desert https://www.westernsydney.edu.au/hie/stories/news_archive/solar_panels_sahara_climate_change https://www.westernsydney.edu.au/hie/stories/news_archive/so...
glenstein 1y ago
1% from a Dyson Sphere would be a better energy return than 100% efficiency from any conventional energy sorce. Similarly, 20% from solar is competitive with 60% from nuclear, 50% from coal, and is easily better than 100% from my neighbor Dan riding a bicycle powered electricity generator. You can't cite efficiency percentages in a vacuum to imply they are a better or worse than alternatives, because those aren't percentages of the same kinds of things, and they don't tell you about the economics, production in absolute terms or EROEI.
- Ardon 1y ago
  The solar panels would overheat (and lose efficiency), since ~80% of the solar energy hitting it is absorbed as (mostly) heat. Generating solar energy in deserts is often done with a mirror based heating system for this reason.
  - 1y ago