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Have people looked at combining gas generation and wind power, would being able to generate gas when there was too much electricity change the capacity factor e

Have people looked at combining gas generation and wind power, would being able to generate gas when there was too much electricity change the capacity factor equation?

mschuster91 5y ago
We don't have anything near that scale in power-to-gas. And even if we did have, power-to-hydrogen still is at only 60-70% efficency.
- dahfizz 5y ago
  What is the efficiency of hydrogen-to-power? Or, the round trip efficiency of using hydrogen as storage?
  - bjourne 5y ago
    About 60-70%. Possibly it could be improved with better electrolysis techniques or large-scale facilities. Some Swedish companies are pushing for that solution: https://www.hybritdevelopment.se/en/a-fossil-free-future/ https://www.hybritdevelopment.se/en/a-fossil-free-future/ For now it's only for the steel industry but could in theory be used for other parts of the grid too.
    - VBprogrammer 5y ago
      A 60-70% round trip efficiency would be very impressive for round trip efficiency of electricity to hydrogen and back. Its in the same ballpark as pumped storage. I can only assume it's assuming using fuel cells which are 90% efficient for the conversion to electricity. I'm not convinced these have really been deployed at that scale before, the biggest fuel cells I'm aware of are used in non-nuclear submarines where cost is not a priority.
- 7952 5y ago
  That efficiency could be good enough if you can buy the energy cheap and sell high.
  - mschuster91 5y ago
    The problem is, the only place where you can make that worth the while is by building out solar in Northern Africa. Unfortunately, the countries in that region are a combination of failed states, governed by dictators, under threat of war or terrorism or pissed off after hundreds of years of Western colonial powers coming in, taking natural resources and leaving no meaningful income and perspectives to the locals. There's no easy solution for a single one of these problems, much less for all of them.
    - Ekaros 5y ago
      Also knowing the usual imperialist power games played there even if we would with huge cost stabilise the area, an other power coming in destabilizing it again is quite a big risk...
    - 7952 5y ago
      No it could work in other places. You buy 1 unit of energy for £50 per unit. And then sell at £150 per unit, or £90 for your remaining 0.6 units. The profit is from the price difference. You make money from arbitrage. And this is the kind of price difference you would expect in a grid with lots of intermittent sources. And the cheaper the source commodity becomes the less efficiency really matters.
      - hkt 5y ago
        This is essentially the principle of a virtual powerplant - household tariffs like Octopus Agile (price fluctuations every 30 minutes) with a home battery make it possible to do this at quite a small (eg household) scale. A bigger operator could find bigger returns if they could make it work. I think there's something to be said for storing excess energy like this - it beats paying into fossil fuel economies.
      - 5y ago
yodelshady 5y ago
I'm not currently aware of any wind turbines in the UK being powered down due to lack of demand, so the 30% capacity factor is exclusively due to lack of supply, i.e. no wind to turn the turbines. It's definitely worth looking at with another 3x wind capacity or so.
- pydry 5y ago
  We should probably be building more pumped water storage now in anticipation of wind cracking 100% of demand. There's coire glas being built already but we'll need more, and it takes about 2x as long to build as a wind farm does.
- Gwypaas 5y ago
  The latest ~15 MW off-shore monsters are up to capacity factors of 60-64% now. https://www.ge.com/renewableenergy/wind-energy/offshore-wind/haliade-x-offshore-turbine https://www.ge.com/renewableenergy/wind-energy/offshore-wind... https://www.vestas.com/en/products/offshore/V236-15MW https://www.vestas.com/en/products/offshore/V236-15MW
  - yodelshady 5y ago
    I... put politely, don't understand how manufacturers can make that claim, it depends on exogenous factors. That said, you're right, the newest turbines are impressive structures and more consistent at their job. Also that said, andy_ppp is right, or will be soon. If you want to make a dent in our fossil fuel needs on a cold windless day, you'll have giant globs of excess energy on warm windy days, that is simply orders of magnitude more than any practically-costed battery can store. At that point, who cares if electrolysis is only 30% efficient?
    - Gwypaas 5y ago
      Your margins care, since those are a factor of installation cost, marginal cost and energy lost due to round trip efficiency. That 70% loss defines the lowest possible price difference between buy cheap power and sell expensive. Therefore any other smart consumer or storage has that margin to work against, to compete you out of the market. This is why batteries can work, in some cases. But it is a pure inefficiency that will find a minimum equilibrium.

Have people looked at combining gas generation and wind power, would being able to generate gas when there was too much electricity change the capacity factor equation?

mschuster91 5y ago

We don't have anything near that scale in power-to-gas. And even if we did have, power-to-hydrogen still is at only 60-70% efficency.

dahfizz 5y ago
What is the efficiency of hydrogen-to-power? Or, the round trip efficiency of using hydrogen as storage?
- bjourne 5y ago
  About 60-70%. Possibly it could be improved with better electrolysis techniques or large-scale facilities. Some Swedish companies are pushing for that solution: https://www.hybritdevelopment.se/en/a-fossil-free-future/ https://www.hybritdevelopment.se/en/a-fossil-free-future/ For now it's only for the steel industry but could in theory be used for other parts of the grid too.
  - VBprogrammer 5y ago
    A 60-70% round trip efficiency would be very impressive for round trip efficiency of electricity to hydrogen and back. Its in the same ballpark as pumped storage. I can only assume it's assuming using fuel cells which are 90% efficient for the conversion to electricity. I'm not convinced these have really been deployed at that scale before, the biggest fuel cells I'm aware of are used in non-nuclear submarines where cost is not a priority.
7952 5y ago
That efficiency could be good enough if you can buy the energy cheap and sell high.
- mschuster91 5y ago
  The problem is, the only place where you can make that worth the while is by building out solar in Northern Africa. Unfortunately, the countries in that region are a combination of failed states, governed by dictators, under threat of war or terrorism or pissed off after hundreds of years of Western colonial powers coming in, taking natural resources and leaving no meaningful income and perspectives to the locals. There's no easy solution for a single one of these problems, much less for all of them.
  - Ekaros 5y ago
    Also knowing the usual imperialist power games played there even if we would with huge cost stabilise the area, an other power coming in destabilizing it again is quite a big risk...
  - 7952 5y ago
    No it could work in other places. You buy 1 unit of energy for £50 per unit. And then sell at £150 per unit, or £90 for your remaining 0.6 units. The profit is from the price difference. You make money from arbitrage. And this is the kind of price difference you would expect in a grid with lots of intermittent sources. And the cheaper the source commodity becomes the less efficiency really matters.
    - hkt 5y ago
      This is essentially the principle of a virtual powerplant - household tariffs like Octopus Agile (price fluctuations every 30 minutes) with a home battery make it possible to do this at quite a small (eg household) scale. A bigger operator could find bigger returns if they could make it work. I think there's something to be said for storing excess energy like this - it beats paying into fossil fuel economies.
    - 5y ago

yodelshady 5y ago

I'm not currently aware of any wind turbines in the UK being powered down due to lack of demand, so the 30% capacity factor is exclusively due to lack of supply, i.e. no wind to turn the turbines. It's definitely worth looking at with another 3x wind capacity or so.

pydry 5y ago
We should probably be building more pumped water storage now in anticipation of wind cracking 100% of demand. There's coire glas being built already but we'll need more, and it takes about 2x as long to build as a wind farm does.
Gwypaas 5y ago
The latest ~15 MW off-shore monsters are up to capacity factors of 60-64% now. https://www.ge.com/renewableenergy/wind-energy/offshore-wind/haliade-x-offshore-turbine https://www.ge.com/renewableenergy/wind-energy/offshore-wind... https://www.vestas.com/en/products/offshore/V236-15MW https://www.vestas.com/en/products/offshore/V236-15MW
- yodelshady 5y ago
  I... put politely, don't understand how manufacturers can make that claim, it depends on exogenous factors. That said, you're right, the newest turbines are impressive structures and more consistent at their job. Also that said, andy_ppp is right, or will be soon. If you want to make a dent in our fossil fuel needs on a cold windless day, you'll have giant globs of excess energy on warm windy days, that is simply orders of magnitude more than any practically-costed battery can store. At that point, who cares if electrolysis is only 30% efficient?
  - Gwypaas 5y ago
    Your margins care, since those are a factor of installation cost, marginal cost and energy lost due to round trip efficiency. That 70% loss defines the lowest possible price difference between buy cheap power and sell expensive. Therefore any other smart consumer or storage has that margin to work against, to compete you out of the market. This is why batteries can work, in some cases. But it is a pure inefficiency that will find a minimum equilibrium.