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Do you have any sources for your claim of batteries multiplying the cost for renewables by "5, 10 or more" in a realistic grid scenario? Did you take into accou

by fsh 7y ago

Do you have any sources for your claim of batteries multiplying the cost for renewables by "5, 10 or more" in a realistic grid scenario? Did you take into account that most energy storage is done with hydro, not batteries? I haven't had time to carefully review the literature, but there seem to be quite a few papers that claim that storage for a 100% renewable grid would not be such a big issue.

wazoox 7y ago
Basically renewables produce 15-20% of the time (30 to 40% for offshore wind). Let's be generous and start with 30% of the time. You need storage to provide 70% of the demand. So for every GWh or required power, you need 700MWh of storage. The famed Tesla Mega battery is a puny 129MWh... You must account for the fact that there could be no sun or no wind for several days, therefore be able to store incredible amounts of power, far beyond the scale we know of.Then the sheer space required for renewable power is staggering. As I said, the biggest solar plants are 600MW to 1GW and occupy tens of square km. Now imagine supplying 10s of GW this way. As someone joked on twitter, if you covered the whole Fukushima exclusion zone (250 km2 or so)with solar panels, it wouldn't come close to the Daishi nuclear plant annual power output. For a detailed discussion on these matters, see https://jancovici.com/en/energy-transition/renewables/100-renewable-electricity-at-no-extra-cost-a-piece-of-cake/ https://jancovici.com/en/energy-transition/renewables/100-re...
- deleted 7y ago
  [deleted]
- fsh 7y ago
  Your calculation does not make much sense (GWh isn't even a unit of power). One would have to look at actual power production and consumption curves in order to estimate the required storage capacity. Battery storage is still very exotic, pretty much the entire capacity is provided by hydro nowadays. Current-gen solar panels average about 30 W/m² over the year in Japan's latitude and climate. So a solar park the size of the Fukushima exclusion zone would produce around 7 GW on average which is more than the combined nameplate capacity of the six reactors (5.3 GW). Supplying the entire country with electricity (~114 GW) would require about 3800 km² of solar panels, or about 1% of Japan's area.
  - wazoox 7y ago
    GWh is the most relevant unit: the quantity of energy we need around the year. GW of nominal output is relevant for nuclear or fire-based power that can produce 24h/24 365d/year, but completely irrelevant for wind and solar that provide power only part time. A 1GW solar plant outs 1GW once every sunny day, at noon. The rest of the day, it produces less, and nothing at all 12 hours a day. A 1GW solar plant roughly produces 3GWh a day. OTOH, a 1GW nuclear plant produces on a yearly average 800MWh every hour, every day and night. So at the end of the year your 1GW solar plant produced a grand total of 1100GWh, while your 1GW nuclear (or coal-fired, or gas-fired) power plant produced 7000GWh. Plus your solar panel will provide energy mostly around noon, need it or not. While the nuclear (or gas, or coal) plant will provide power exactly when you need it. Wind is even worse than solar, because production yield isn't even particularly predictable. So when wind blows, electricity goes into the grid without any consideration for the need for it. That's why its price drops to negative at times: because we don't need it. That's not because wind is wonderfully efficient or something. It's because building wind farms is a fantastic misallocation of resources. We're literally spending money for electricity worth almost nothing, and it won't ever recoup its costs. That's why Germany, after having dumped 300 billions euros on wind farms in 20 years, stop building them altogether in 2018. At some point some accountant did the math.
    - fsh 7y ago
      It is completely obvious that renewables require significantly more storage capacity than other power sources. However, a lot of experts seem to believe that this is not nearly as big of an issue as you are implying. As for wind energy, you are completely wrong. In 2019 25% of Germany's electricity was generated by wind (compared to 13% nuclear). This has significantly reduced the fossil fuel consumption and CO2 emissions. The main reason for halting construction is that conservative politicians have passed idiotic NIMBY regulations that now make it very difficult to build new on-shore wind farms. Somehow they even managed to convince a signify fraction of the population that wind turbines are somehow dangerous (probably the same fraction that believes in electro-smog).
      - 7y ago
wazoox 7y ago
I like that people downvote without providing any argument, any numbers or any source. Slow clap. Enjoy your blackouts.
- dang 7y ago
  Can you please read https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here? They explicitly ask you not to go on about downvoting like this. In addition to being tedious and doing no good, such comments often end up being false, once users come along and (as they typically do) give corrective upvotes to the unfairly-downvoted comment. Unfortunately, posts like yours here don't then garbage-collect themselves—they stick around, adding noise to the thread. That's one reason we ask people not to post them.

by fsh 7y ago

wazoox 7y ago

Basically renewables produce 15-20% of the time (30 to 40% for offshore wind). Let's be generous and start with 30% of the time. You need storage to provide 70% of the demand. So for every GWh or required power, you need 700MWh of storage. The famed Tesla Mega battery is a puny 129MWh... You must account for the fact that there could be no sun or no wind for several days, therefore be able to store incredible amounts of power, far beyond the scale we know of.Then the sheer space required for renewable power is staggering. As I said, the biggest solar plants are 600MW to 1GW and occupy tens of square km. Now imagine supplying 10s of GW this way. As someone joked on twitter, if you covered the whole Fukushima exclusion zone (250 km2 or so)with solar panels, it wouldn't come close to the Daishi nuclear plant annual power output. For a detailed discussion on these matters, see https://jancovici.com/en/energy-transition/renewables/100-renewable-electricity-at-no-extra-cost-a-piece-of-cake/ https://jancovici.com/en/energy-transition/renewables/100-re...

deleted 7y ago
[deleted]
fsh 7y ago
Your calculation does not make much sense (GWh isn't even a unit of power). One would have to look at actual power production and consumption curves in order to estimate the required storage capacity. Battery storage is still very exotic, pretty much the entire capacity is provided by hydro nowadays. Current-gen solar panels average about 30 W/m² over the year in Japan's latitude and climate. So a solar park the size of the Fukushima exclusion zone would produce around 7 GW on average which is more than the combined nameplate capacity of the six reactors (5.3 GW). Supplying the entire country with electricity (~114 GW) would require about 3800 km² of solar panels, or about 1% of Japan's area.
- wazoox 7y ago
  GWh is the most relevant unit: the quantity of energy we need around the year. GW of nominal output is relevant for nuclear or fire-based power that can produce 24h/24 365d/year, but completely irrelevant for wind and solar that provide power only part time. A 1GW solar plant outs 1GW once every sunny day, at noon. The rest of the day, it produces less, and nothing at all 12 hours a day. A 1GW solar plant roughly produces 3GWh a day. OTOH, a 1GW nuclear plant produces on a yearly average 800MWh every hour, every day and night. So at the end of the year your 1GW solar plant produced a grand total of 1100GWh, while your 1GW nuclear (or coal-fired, or gas-fired) power plant produced 7000GWh. Plus your solar panel will provide energy mostly around noon, need it or not. While the nuclear (or gas, or coal) plant will provide power exactly when you need it. Wind is even worse than solar, because production yield isn't even particularly predictable. So when wind blows, electricity goes into the grid without any consideration for the need for it. That's why its price drops to negative at times: because we don't need it. That's not because wind is wonderfully efficient or something. It's because building wind farms is a fantastic misallocation of resources. We're literally spending money for electricity worth almost nothing, and it won't ever recoup its costs. That's why Germany, after having dumped 300 billions euros on wind farms in 20 years, stop building them altogether in 2018. At some point some accountant did the math.
  - fsh 7y ago
    It is completely obvious that renewables require significantly more storage capacity than other power sources. However, a lot of experts seem to believe that this is not nearly as big of an issue as you are implying. As for wind energy, you are completely wrong. In 2019 25% of Germany's electricity was generated by wind (compared to 13% nuclear). This has significantly reduced the fossil fuel consumption and CO2 emissions. The main reason for halting construction is that conservative politicians have passed idiotic NIMBY regulations that now make it very difficult to build new on-shore wind farms. Somehow they even managed to convince a signify fraction of the population that wind turbines are somehow dangerous (probably the same fraction that believes in electro-smog).
    - 7y ago

wazoox 7y ago

I like that people downvote without providing any argument, any numbers or any source. Slow clap. Enjoy your blackouts.

dang 7y ago
Can you please read https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here? They explicitly ask you not to go on about downvoting like this. In addition to being tedious and doing no good, such comments often end up being false, once users come along and (as they typically do) give corrective upvotes to the unfairly-downvoted comment. Unfortunately, posts like yours here don't then garbage-collect themselves—they stick around, adding noise to the thread. That's one reason we ask people not to post them.