4 ms·

Solar and wind are by their very inherent nature intermittent sources of power

by troupo 2y ago

lomase 2y ago
You can not stop a nuclear reactor to fit the grid needs.
- troupo 2y ago
  You cannot power up solar panels at night, or wind turbines when there's no wind. As for nuclear, you don't need to stop them. Instead they provide a base load so you don't need to ridiculously overprovision other power sources. And they are flexible enough to go 50%-100% quickly: https://www.oecd-nea.org/upload/docs/application/pdf/2021-12/technical_and_economic_aspects_of_load_following_with_nuclear_power_plants.pdf https://www.oecd-nea.org/upload/docs/application/pdf/2021-12...
  - lomase 2y ago
    "You cannot power up solar panels at night, or wind turbines when there's no wind." Amazing insight.
ben_w 2y ago
Not inherent nature, just economics and politics. Wind always blows somewhere, the sun always shines somewhere. Making a global power grid is something which I don't expect anyone will do in the next 15 years, but if anyone does I'd be least surprised if it's China on a belt-and-road type project. Batteries are necessary for electric vehicles, and I do expect >50% of land motor vehicles in use worldwide to be electric within 15 years of today; that scale is sufficient to invalidate concerns about intermittent renewable generation in most (but not all) places even without a global grid.
- lazide 2y ago
  And how far of a cable would you need to get 24/7 solar power? Because based on my math, it would have to cross a lot of timezones - including ones with a lot of people that would be happy to chop that cable if it meant screwing with the US.
  - ben_w 2y ago
    40,000 km will always be enough. A single cable is a bad idea for many reasons, but "it might get cut" isn't one of them, as at this scale it's the kind of thing that the whole world is using, so (0) nobody actually benefits from cutting it, (1) it's carrying order of a terrawatt at any given moment, so if you made it a single cable the magnetic field alone will mess with your cutting equipment, and (2) for reasonable resistance it's a cross section of about a square meter (1 Ω and ~1 year global aluminium production for that cross section at 40,000 km), so even a literal detonation of a Little Boy nuke 500 meters from it wouldn't make a dent.
    - lazide 2y ago
      A country like Russia will always benefit from cutting such a cable. Anything else, like the rest of this post, is pure fantasy.
      - ben_w 2y ago
        If the cable (or one of them: again it's bad to make it just one, just physically spreading out that 1m^2 into a hundred cables of 10cm by 10cm makes it a lot less risky) goes through Russia, and they cut it, the effect is that immediately Russia stops trading energy. At best, this is a loss of income. At worst, it means their own lights go off because now they aren't getting anyone else's electricity in their own night and their own winter. What exactly do you think is fantastical? Using one year's production of one element? Because I'd already noted that the political aspects are severe enough that it's unlikely for anyone to build at this scale any time soon, and that only one country would be capable but even then it would be a surprise.
        2y ago
- troupo 2y ago
  > Not inherent nature, just economics and politics. I didn't know that night and calm days with no wind are economics and politics > Wind always blows somewhere, the sun always shines somewhere. Key word: somewhere. How much wind and sun needs to shine somewhere to cover the needs of, say Europe, on a quiet night? Note that that somewhere will need to cover that somewhere's needs, too. Note: you're also likely underestimating how large the area covered by nighttime is. Here are two examples: https://www.timeanddate.com/worldclock/sunearth.html?iso=20240703T2228 https://www.timeanddate.com/worldclock/sunearth.html?iso=202... and https://www.timeanddate.com/worldclock/sunearth.html?iso=20240704T0528 https://www.timeanddate.com/worldclock/sunearth.html?iso=202... I'm guessing your proposal is to pump energy from China to the US through the Pacific Ocean? > Making a global power grid is something which I don't expect anyone will do in the next 15 years Or ever. You underestimate the size of the Earth > I'd be least surprised if it's China on a belt-and-road type project. You know that Europe has a unified power grid, right? And that the US has three major grid regions? > Batteries are necessary for electric vehicles, and I do expect >50% of land motor vehicles in use worldwide to be electric within 15 years of today; that scale is sufficient to invalidate concerns about intermittent renewable generation in most wat? Just because you have batteries in electric vehicles doesn't mean you have enough batteries to provide electricity for a country/continent.
  - ben_w 2y ago
    > I didn't know that night and calm days with no wind are economics and politics Planet is round. Your winter solstice midnight is someone else's midsummer midday. Convincing everyone to join up, that's economics and politics. > How much wind and sun needs to shine somewhere to cover the needs of, say Europe, on a quiet night? I've seen EU night power draw is about 87-107 GW, so 85% of the area of Rhode Island but in Australia: http://www.wolframalpha.com/input/?i=107%20GW%20%2F%20%281%20kW%2Fm%5E2%20%2A%200.2%20%2A%200.2%29 http://www.wolframalpha.com/input/?i=107%20GW%20%2F%20%281%2... > Note that that somewhere will need to cover that somewhere's needs, too. And our day provides their night. It's called "trade". > you're also likely underestimating how large the area covered by nighttime Your links are, bluntly, an insult. Everyone here knows the thing they show. ~50% of the planet technically, more than that in practice because local structure; average capacity factor (24 hour including night) of PV is 10%, so I'd be happy to approximate that as a 12 hour day-focused capacity factor of 20%. > I'm guessing your proposal is to pump energy from China to the US through the Pacific Ocean? China has an actual proposal for a demo project to go further across the Pacific and connect to Chile. If that works, they might feel like making it thicker and longer. > Or ever. You underestimate the size of the Earth 40,000 km, requires 1 m^2 cross section to keep the resistance down to 1 Ω when using Aluminium; this requires just over a year of current global production of aluminium and has a material cost of a few hundred billion dollars at current metal prices. > You know that Europe has a unified power grid, right? And that the US has three major grid regions? Which is why it's a political problem. There will always be a place like Texas is now that wants to be difficult and independent even at its own expense. > Just because you have batteries in electric vehicles doesn't mean you have enough batteries to provide electricity for a country/continent. There's approximately a billion cars on the road today. Half a billion cars multiplied by let's say 60 kWh per car is 30 TWh; current global electricity use (which includes daytime) is about 2 TW, that's therefore 15 hours before I include trucks, bikes, busses, etc. But night use is lower than day use, so in practice the capacity to build that many batteries is also the capacity to build enough batteries for overnight use too.

Solar and wind are by their very inherent nature intermittent sources of power

by troupo 2y ago

Solar and wind are by their very inherent nature intermittent sources of power

lomase 2y ago

You can not stop a nuclear reactor to fit the grid needs.

troupo 2y ago
You cannot power up solar panels at night, or wind turbines when there's no wind. As for nuclear, you don't need to stop them. Instead they provide a base load so you don't need to ridiculously overprovision other power sources. And they are flexible enough to go 50%-100% quickly: https://www.oecd-nea.org/upload/docs/application/pdf/2021-12/technical_and_economic_aspects_of_load_following_with_nuclear_power_plants.pdf https://www.oecd-nea.org/upload/docs/application/pdf/2021-12...
- lomase 2y ago
  "You cannot power up solar panels at night, or wind turbines when there's no wind." Amazing insight.

ben_w 2y ago

Not inherent nature, just economics and politics. Wind always blows somewhere, the sun always shines somewhere. Making a global power grid is something which I don't expect anyone will do in the next 15 years, but if anyone does I'd be least surprised if it's China on a belt-and-road type project. Batteries are necessary for electric vehicles, and I do expect >50% of land motor vehicles in use worldwide to be electric within 15 years of today; that scale is sufficient to invalidate concerns about intermittent renewable generation in most (but not all) places even without a global grid.

lazide 2y ago
And how far of a cable would you need to get 24/7 solar power? Because based on my math, it would have to cross a lot of timezones - including ones with a lot of people that would be happy to chop that cable if it meant screwing with the US.
- ben_w 2y ago
  40,000 km will always be enough. A single cable is a bad idea for many reasons, but "it might get cut" isn't one of them, as at this scale it's the kind of thing that the whole world is using, so (0) nobody actually benefits from cutting it, (1) it's carrying order of a terrawatt at any given moment, so if you made it a single cable the magnetic field alone will mess with your cutting equipment, and (2) for reasonable resistance it's a cross section of about a square meter (1 Ω and ~1 year global aluminium production for that cross section at 40,000 km), so even a literal detonation of a Little Boy nuke 500 meters from it wouldn't make a dent.
  - lazide 2y ago
    A country like Russia will always benefit from cutting such a cable. Anything else, like the rest of this post, is pure fantasy.
    - ben_w 2y ago
      If the cable (or one of them: again it's bad to make it just one, just physically spreading out that 1m^2 into a hundred cables of 10cm by 10cm makes it a lot less risky) goes through Russia, and they cut it, the effect is that immediately Russia stops trading energy. At best, this is a loss of income. At worst, it means their own lights go off because now they aren't getting anyone else's electricity in their own night and their own winter. What exactly do you think is fantastical? Using one year's production of one element? Because I'd already noted that the political aspects are severe enough that it's unlikely for anyone to build at this scale any time soon, and that only one country would be capable but even then it would be a surprise.
      - 2y ago
troupo 2y ago
> Not inherent nature, just economics and politics. I didn't know that night and calm days with no wind are economics and politics > Wind always blows somewhere, the sun always shines somewhere. Key word: somewhere. How much wind and sun needs to shine somewhere to cover the needs of, say Europe, on a quiet night? Note that that somewhere will need to cover that somewhere's needs, too. Note: you're also likely underestimating how large the area covered by nighttime is. Here are two examples: https://www.timeanddate.com/worldclock/sunearth.html?iso=20240703T2228 https://www.timeanddate.com/worldclock/sunearth.html?iso=202... and https://www.timeanddate.com/worldclock/sunearth.html?iso=20240704T0528 https://www.timeanddate.com/worldclock/sunearth.html?iso=202... I'm guessing your proposal is to pump energy from China to the US through the Pacific Ocean? > Making a global power grid is something which I don't expect anyone will do in the next 15 years Or ever. You underestimate the size of the Earth > I'd be least surprised if it's China on a belt-and-road type project. You know that Europe has a unified power grid, right? And that the US has three major grid regions? > Batteries are necessary for electric vehicles, and I do expect >50% of land motor vehicles in use worldwide to be electric within 15 years of today; that scale is sufficient to invalidate concerns about intermittent renewable generation in most wat? Just because you have batteries in electric vehicles doesn't mean you have enough batteries to provide electricity for a country/continent.
- ben_w 2y ago
  > I didn't know that night and calm days with no wind are economics and politics Planet is round. Your winter solstice midnight is someone else's midsummer midday. Convincing everyone to join up, that's economics and politics. > How much wind and sun needs to shine somewhere to cover the needs of, say Europe, on a quiet night? I've seen EU night power draw is about 87-107 GW, so 85% of the area of Rhode Island but in Australia: http://www.wolframalpha.com/input/?i=107%20GW%20%2F%20%281%20kW%2Fm%5E2%20%2A%200.2%20%2A%200.2%29 http://www.wolframalpha.com/input/?i=107%20GW%20%2F%20%281%2... > Note that that somewhere will need to cover that somewhere's needs, too. And our day provides their night. It's called "trade". > you're also likely underestimating how large the area covered by nighttime Your links are, bluntly, an insult. Everyone here knows the thing they show. ~50% of the planet technically, more than that in practice because local structure; average capacity factor (24 hour including night) of PV is 10%, so I'd be happy to approximate that as a 12 hour day-focused capacity factor of 20%. > I'm guessing your proposal is to pump energy from China to the US through the Pacific Ocean? China has an actual proposal for a demo project to go further across the Pacific and connect to Chile. If that works, they might feel like making it thicker and longer. > Or ever. You underestimate the size of the Earth 40,000 km, requires 1 m^2 cross section to keep the resistance down to 1 Ω when using Aluminium; this requires just over a year of current global production of aluminium and has a material cost of a few hundred billion dollars at current metal prices. > You know that Europe has a unified power grid, right? And that the US has three major grid regions? Which is why it's a political problem. There will always be a place like Texas is now that wants to be difficult and independent even at its own expense. > Just because you have batteries in electric vehicles doesn't mean you have enough batteries to provide electricity for a country/continent. There's approximately a billion cars on the road today. Half a billion cars multiplied by let's say 60 kWh per car is 30 TWh; current global electricity use (which includes daytime) is about 2 TW, that's therefore 15 hours before I include trucks, bikes, busses, etc. But night use is lower than day use, so in practice the capacity to build that many batteries is also the capacity to build enough batteries for overnight use too.