4 ms·

Find me high-voltage high-amperage connections on the side of the freeway though.

by zymhan 8y ago

Gravityloss 8y ago
Denmark is small, flat and relatively populated and rich. Probably you're never far from a high voltage transmission line.
rcMgD2BwE72F 8y ago
That doesn't cost much (far less than a gas equivalent) and can be installed alongside highways within weeks. If people purchase EV _en masse_, they'll have charging stations everywhere. There's no egg/chicken problem here.
- ben_w 8y ago
  Worldwide, transport energy use is about 150% total electricity use — 30PWh/y vs. 20PWh/y. I’m not saying we can’t upgrade production (I’m actually significantly more optimistic than the best case IAE estimates), but it’s not as trivial as just installing some new wires and transformers.
  - apcragg 8y ago
    I'm curious, is that only non-point-to-point personal transportation or does it include all forms (e.g. ocean shipping, rail, public transport)?
    - ben_w 8y ago
      That’s very good point, looking at my source the answer appears to be “everything”. I will try to remember that in future. However, my point is only that we will need non trivial increases in electricity production, rather than any specific number. That point still stands.
  - rcMgD2BwE72F 8y ago
    You could have a solar farm and some batteries close to each stations. It's not trivial but it isn't a bottleneck either.
    - ben_w 8y ago
      When I ran the numbers for the USA, it was something along the lines of adding a 1m wide strip of normal efficiency PV alongside the entire length of the interstate network. I’ve not looked at the size of any other highway system relative to population density but I do know that Denmark gets less sunlight than the USA average. Like I said in my original comment: I’m optimistic, I just don’t think it’s trivial. To put it another way, I think it’s something that requires a government rather than being achievable purely with the private sector. That might mean just incentives and template plans, or it might require government to commission things, but it’s that sort of scale.
  - tialaramex 8y ago
    Yeah, so, the first thing to know about that is ICE is ludicrously inefficient. Spinning all that metal at variable speed with tiny explosions is, unsurprisingly, not the best way to turn high density fuels into energy. The thing ICE had on its side is the energy density, on other metrics it's a bad deal (hence why free charging for EVs is affordable) So if you have 400MW of ICE cars you don't need 400MW of electricity to replace that, something more like 80-100MW is more like it IIRC. The infrastructure build cost isn't zero, but it's much less than this 150% metric suggests.
    - sbradford26 8y ago
      Getting some rough numbers from Wikipedia it looks like most common new cars are sitting around 35% thermal efficiency. I believe a formula 1 engine achieved 50% thermal efficiency recently but the cost of that is obscenely high. Where as electric motor efficiency easily hits 90%+.
    - sfsafa 8y ago
      "ludicrously inefficient" No, they're not. They're, as implemented in a car, a ludicrous example of engineering compromises. Put a hybrid drive methane spark-ignition high compression engine and you'll have similar CO2 emissions from a e-car powered by a thermal plant (the vast majority of our power). It'll cost as much as a Tesla too.
    - ams6110 8y ago
      It's also quite inefficient to convert hydrocarbon energy to mechanical energy to electrical energy to chemical energy back to electrical energy and then back to mechanical energy, as an electric car does. ICE goes straight from hydrocarbon to mechanical. It would not surprise me if it's more efficient, though I don't know.
kalms 8y ago
They're already common along the highways in DK (incl. a few Superchargers) Map: https://www.google.com/search?client=safari&rls=en&q=tesla+supercharger+denmark&npsic=0&rflfq=1&rlha=0&rllag=55585886,12388391,17768&tbm=lcl&ved=2ahUKEwiP6f2R2-rdAhWjsaQKHfiPCh8QtgN6BAgAEAQ&tbs=lrf:!2m1!1e3!3sIAE,lf:1,lf_ui:4&rldoc=1#rlfi=hd:;si:;mv:!3m8!1m3!1d1007839.8511401694!2d9.261467997194814!3d56.472387334207546!3m2!1i1011!2i686!4f13.1 https://www.google.com/search?client=safari&rls=en&q=tesla+s...

Find me high-voltage high-amperage connections on the side of the freeway though.

by zymhan 8y ago

Find me high-voltage high-amperage connections on the side of the freeway though.

Denmark is small, flat and relatively populated and rich. Probably you're never far from a high voltage transmission line.

rcMgD2BwE72F 8y ago

That doesn't cost much (far less than a gas equivalent) and can be installed alongside highways within weeks. If people purchase EV _en masse_, they'll have charging stations everywhere. There's no egg/chicken problem here.

ben_w 8y ago
Worldwide, transport energy use is about 150% total electricity use — 30PWh/y vs. 20PWh/y. I’m not saying we can’t upgrade production (I’m actually significantly more optimistic than the best case IAE estimates), but it’s not as trivial as just installing some new wires and transformers.
- apcragg 8y ago
  I'm curious, is that only non-point-to-point personal transportation or does it include all forms (e.g. ocean shipping, rail, public transport)?
  - ben_w 8y ago
    That’s very good point, looking at my source the answer appears to be “everything”. I will try to remember that in future. However, my point is only that we will need non trivial increases in electricity production, rather than any specific number. That point still stands.
- rcMgD2BwE72F 8y ago
  You could have a solar farm and some batteries close to each stations. It's not trivial but it isn't a bottleneck either.
  - ben_w 8y ago
    When I ran the numbers for the USA, it was something along the lines of adding a 1m wide strip of normal efficiency PV alongside the entire length of the interstate network. I’ve not looked at the size of any other highway system relative to population density but I do know that Denmark gets less sunlight than the USA average. Like I said in my original comment: I’m optimistic, I just don’t think it’s trivial. To put it another way, I think it’s something that requires a government rather than being achievable purely with the private sector. That might mean just incentives and template plans, or it might require government to commission things, but it’s that sort of scale.
- tialaramex 8y ago
  Yeah, so, the first thing to know about that is ICE is ludicrously inefficient. Spinning all that metal at variable speed with tiny explosions is, unsurprisingly, not the best way to turn high density fuels into energy. The thing ICE had on its side is the energy density, on other metrics it's a bad deal (hence why free charging for EVs is affordable) So if you have 400MW of ICE cars you don't need 400MW of electricity to replace that, something more like 80-100MW is more like it IIRC. The infrastructure build cost isn't zero, but it's much less than this 150% metric suggests.
  - sbradford26 8y ago
    Getting some rough numbers from Wikipedia it looks like most common new cars are sitting around 35% thermal efficiency. I believe a formula 1 engine achieved 50% thermal efficiency recently but the cost of that is obscenely high. Where as electric motor efficiency easily hits 90%+.
  - sfsafa 8y ago
    "ludicrously inefficient" No, they're not. They're, as implemented in a car, a ludicrous example of engineering compromises. Put a hybrid drive methane spark-ignition high compression engine and you'll have similar CO2 emissions from a e-car powered by a thermal plant (the vast majority of our power). It'll cost as much as a Tesla too.
  - ams6110 8y ago
    It's also quite inefficient to convert hydrocarbon energy to mechanical energy to electrical energy to chemical energy back to electrical energy and then back to mechanical energy, as an electric car does. ICE goes straight from hydrocarbon to mechanical. It would not surprise me if it's more efficient, though I don't know.

kalms 8y ago

They're already common along the highways in DK (incl. a few Superchargers) Map: https://www.google.com/search?client=safari&rls=en&q=tesla+supercharger+denmark&npsic=0&rflfq=1&rlha=0&rllag=55585886,12388391,17768&tbm=lcl&ved=2ahUKEwiP6f2R2-rdAhWjsaQKHfiPCh8QtgN6BAgAEAQ&tbs=lrf:!2m1!1e3!3sIAE,lf:1,lf_ui:4&rldoc=1#rlfi=hd:;si:;mv:!3m8!1m3!1d1007839.8511401694!2d9.261467997194814!3d56.472387334207546!3m2!1i1011!2i686!4f13.1 https://www.google.com/search?client=safari&rls=en&q=tesla+s...