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I completely agree: his introductory mention of the importance of good numbers to inform policy got me hopeful, and then he ignored storage which is possibly th

I completely agree: his introductory mention of the importance of good numbers to inform policy got me hopeful, and then he ignored storage which is possibly the most critical constraint for high renewable penetration. I’m hoping grid scale batteries follow a similar cost reduction to solar but the latest projects which have been built do not inspire confidence. But for some reason this issue is always hand-waved away by the most ardent proponents of renewables. People treat this issue like a football match in that they cheer for their favourite team and ignore their failings.

pydry 3y ago
Grid scale batteries wouldnt be the most cost effective short term storage - pumped storage like coire glas in scotland is. If the UK had another 10 or 15 of those (perfectly doable and economic) that would provide ~8 hours of storage. That would be enough by itself to provide a 94-96% solar/wind powered grid. For that last 3-4% of seasonal/peaking storage and backup nothing beats hydrogen yet. It's only 50% efficient roundtripped but it stores very cheaply for very long periods. If you turned all solar and wind energy into hydrogen and only burned that for electricity it would still be cheaper than power from a nuclear plant. Batteries are probably best used in cars or places which can't connect to pumped storage (which are pretty rare).
- brutusborn 3y ago
  Do you have any figures for the hydrogen storage vs nuclear point? I’m not saying you’re wrong but it goes against intuition. Both hydro storage and hydrogen have the same problem: not all locales have elevated valleys or underground caverns. I’ve heard some talk about using natural gas pipelines for hydrogen storage, but that has its own issues.
  - pydry 3y ago
    https://theecologist.org/2016/feb/17/wind-power-windgas-cheaper-and-greener-hinkley-point-c-nuclear-plant https://theecologist.org/2016/feb/17/wind-power-windgas-chea... The LCOE for nuclear power is roughly ~5x that of solar and wind. If you assumed that the capex and running costs to electrolyze and store 1GWh of power in an underground cavern is roughly the same as it takes to produce it, and that it's about 50% efficient when roundtripped then that would make the stored wind and solar roughly 3/5ths of the cost of nuclear power. This still makes it a lot more expensive than peaking with natural gas. Just because hydrogen storage is competitive with nuclear power doesn't mean it's economically competitive in general. Nuclear power is just way more expensive than people assume, and generally won't get built without a lot of really lavish subsidies (e.g. like Hinkley Point C getting paid 3-5x as much for the same kwh of electricity as everybody else).
    - kgabis 3y ago
      LCOE doesn't account for storage, grid extension necessary and for the fact that nuclear can work for 100 years but solar panels and wind turbines have to be replaced after 20-30. Also, wind and solar where? Solar and wind vary greatly based on where they're installed, yet everyone throws these values around like a solar panel in Greenland would be as efficient as one in Sahara.
      - pydry 3y ago
        It doesn't account for storage (obviously, I think I was pretty clear that this would increase the price from 1/5th to < 3/5ths) or for grid upgrades but LCOE absolutely does account for the projected lifespan of the generating assets. 100 years is, by the way, ludicrously optimistic for a nuclear power plant lifespan. If we ran nuclear power plants that long past their projected lifespans then quite a few would go kaboom.
        kgabis 3y ago
        What did you base your storage cost calculation on? LCOE doesn't account for nuclear running much longer than 20-40 years. And 100 years is not ludicrous, 2 units in the US have been approved to work for 80 years, 100 is not far off if properly maintained.
        pydry 3y ago
        >What did you base your storage cost calculation on? Check the link above. >LCOE doesn't account for nuclear running much longer than 20-40 I can assure you that LCOE does not assume a nuclear power station lasts 20 years. It assumes a normal lifetime - neither too short nor a lifetime that would induce catastrophic risks (e.g. 100 years). I've seen no evidence that standard LCOE models under or overestimate solar/wind/nuclear power lifetimes at different rates and it would be presumptuous to assume that they do without evidence.
        kgabis 3y ago
- cm2187 3y ago
  Several hours? Wind is down to a small fraction for several days regularly [1]. Electricity outage should never happen, so you need to protect against a very high percentile of adverse events. 8h of storage won't do. [1] just look at wind production in the UK for this year or last year https://gridwatch.co.uk/ https://gridwatch.co.uk/
  - pydry 3y ago
    >Graham says that the CSIRO modelling showed that at very high levels of wind and solar, a maximum of half a day’s average demand was needed for storage. In some areas of the grid, only around three hours might be needed. >This is an important point, because some renewable critics say that about a week’s worth of storage is needed https://reneweconomy.com.au/much-storage-needed-solar-wind-powered-grid-47605/ https://reneweconomy.com.au/much-storage-needed-solar-wind-p... Something a lot of people forget or don't notice is that solar and wind anticorrelate. The model takes this into account and doesn't assume a 100% wind grid. That would require a lot more storage, but isn't realistic. There will be some differences between Australia and the UK but it's not going to be hours vs. weeks.
    - cm2187 3y ago
      It defies common sense that you can make up for wind energy being down to almost nothing for days with 8h worth of energy. Solar will never produce much in the uk, and will produce zero during the cold UK winter nights when consumption is maximal.
      - pydry 3y ago
        >will produce zero during the cold UK winter It currently is a cold winter day in the UK and solar is right now providing 1.8GW of power - almost as much as two small nuclear power plants. Do you have a more realistic mathematical model than the one above to cite?
        cm2187 3y ago
        No need for a sophisticated mathematical model. Look at wind production last year per grid watch [1], the two peaks in term of energy consumption (around Feb 2022 and Nov 2022 in the "Last Year (Day Averages)" chart correspond to times when wind was low (and therefore gas was high), some days going to near zero. And last winter was an unusualy warm winter. If I can find examples just looking at one year's worth of data, how is this going to survive a once in 25 or 50 years weather event with no wind for something like 3 weeks? [1] https://gridwatch.co.uk/ https://gridwatch.co.uk/

pydry 3y ago

Grid scale batteries wouldnt be the most cost effective short term storage - pumped storage like coire glas in scotland is. If the UK had another 10 or 15 of those (perfectly doable and economic) that would provide ~8 hours of storage. That would be enough by itself to provide a 94-96% solar/wind powered grid. For that last 3-4% of seasonal/peaking storage and backup nothing beats hydrogen yet. It's only 50% efficient roundtripped but it stores very cheaply for very long periods. If you turned all solar and wind energy into hydrogen and only burned that for electricity it would still be cheaper than power from a nuclear plant. Batteries are probably best used in cars or places which can't connect to pumped storage (which are pretty rare).

brutusborn 3y ago
Do you have any figures for the hydrogen storage vs nuclear point? I’m not saying you’re wrong but it goes against intuition. Both hydro storage and hydrogen have the same problem: not all locales have elevated valleys or underground caverns. I’ve heard some talk about using natural gas pipelines for hydrogen storage, but that has its own issues.
- pydry 3y ago
  https://theecologist.org/2016/feb/17/wind-power-windgas-cheaper-and-greener-hinkley-point-c-nuclear-plant https://theecologist.org/2016/feb/17/wind-power-windgas-chea... The LCOE for nuclear power is roughly ~5x that of solar and wind. If you assumed that the capex and running costs to electrolyze and store 1GWh of power in an underground cavern is roughly the same as it takes to produce it, and that it's about 50% efficient when roundtripped then that would make the stored wind and solar roughly 3/5ths of the cost of nuclear power. This still makes it a lot more expensive than peaking with natural gas. Just because hydrogen storage is competitive with nuclear power doesn't mean it's economically competitive in general. Nuclear power is just way more expensive than people assume, and generally won't get built without a lot of really lavish subsidies (e.g. like Hinkley Point C getting paid 3-5x as much for the same kwh of electricity as everybody else).
  - kgabis 3y ago
    LCOE doesn't account for storage, grid extension necessary and for the fact that nuclear can work for 100 years but solar panels and wind turbines have to be replaced after 20-30. Also, wind and solar where? Solar and wind vary greatly based on where they're installed, yet everyone throws these values around like a solar panel in Greenland would be as efficient as one in Sahara.
    - pydry 3y ago
      It doesn't account for storage (obviously, I think I was pretty clear that this would increase the price from 1/5th to < 3/5ths) or for grid upgrades but LCOE absolutely does account for the projected lifespan of the generating assets. 100 years is, by the way, ludicrously optimistic for a nuclear power plant lifespan. If we ran nuclear power plants that long past their projected lifespans then quite a few would go kaboom.
      - kgabis 3y ago
        What did you base your storage cost calculation on? LCOE doesn't account for nuclear running much longer than 20-40 years. And 100 years is not ludicrous, 2 units in the US have been approved to work for 80 years, 100 is not far off if properly maintained.
        pydry 3y ago
        >What did you base your storage cost calculation on? Check the link above. >LCOE doesn't account for nuclear running much longer than 20-40 I can assure you that LCOE does not assume a nuclear power station lasts 20 years. It assumes a normal lifetime - neither too short nor a lifetime that would induce catastrophic risks (e.g. 100 years). I've seen no evidence that standard LCOE models under or overestimate solar/wind/nuclear power lifetimes at different rates and it would be presumptuous to assume that they do without evidence.
        kgabis 3y ago
cm2187 3y ago
Several hours? Wind is down to a small fraction for several days regularly [1]. Electricity outage should never happen, so you need to protect against a very high percentile of adverse events. 8h of storage won't do. [1] just look at wind production in the UK for this year or last year https://gridwatch.co.uk/ https://gridwatch.co.uk/
- pydry 3y ago
  >Graham says that the CSIRO modelling showed that at very high levels of wind and solar, a maximum of half a day’s average demand was needed for storage. In some areas of the grid, only around three hours might be needed. >This is an important point, because some renewable critics say that about a week’s worth of storage is needed https://reneweconomy.com.au/much-storage-needed-solar-wind-powered-grid-47605/ https://reneweconomy.com.au/much-storage-needed-solar-wind-p... Something a lot of people forget or don't notice is that solar and wind anticorrelate. The model takes this into account and doesn't assume a 100% wind grid. That would require a lot more storage, but isn't realistic. There will be some differences between Australia and the UK but it's not going to be hours vs. weeks.
  - cm2187 3y ago
    It defies common sense that you can make up for wind energy being down to almost nothing for days with 8h worth of energy. Solar will never produce much in the uk, and will produce zero during the cold UK winter nights when consumption is maximal.
    - pydry 3y ago
      >will produce zero during the cold UK winter It currently is a cold winter day in the UK and solar is right now providing 1.8GW of power - almost as much as two small nuclear power plants. Do you have a more realistic mathematical model than the one above to cite?
      - cm2187 3y ago
        No need for a sophisticated mathematical model. Look at wind production last year per grid watch [1], the two peaks in term of energy consumption (around Feb 2022 and Nov 2022 in the "Last Year (Day Averages)" chart correspond to times when wind was low (and therefore gas was high), some days going to near zero. And last winter was an unusualy warm winter. If I can find examples just looking at one year's worth of data, how is this going to survive a once in 25 or 50 years weather event with no wind for something like 3 weeks? [1] https://gridwatch.co.uk/ https://gridwatch.co.uk/