5 ms·

> storage cost is in freefall too That's short-term storage. No seasonal storage technology is at a point where we could just point at a learning curve chart,

> storage cost is in freefall too That's short-term storage. No seasonal storage technology is at a point where we could just point at a learning curve chart, draw a circle around some future intersection point and say "problem solved here".

maxerickson 6y ago
Chemical storage (as methane or whatever) would work fine and the operational side would be more or less carbon neutral. The cost is high compared to burning fossil fuels, but we could do it as a society (have an excess of solar to meet household winter electrical needs and synthesize methane in the summer to use as household heat fuel in the winter). Just pulling numbers out of the darkness, the upfront cost here in a cold region would be ~¼ to ½ the cost of a house. High, but also clearly workable.
deeviant 6y ago
Seasonal storage? That's not a thing. You just scale your solar/wind installations to the part of the season with the least resource (solar and wind do not often have the same low point, either), which is economically feasible because it is cheaper than nuclear (and coal).
- the8472 6y ago
  That dramatically changes cost calculation. Currently "cheaper than X" models don't account for such overcapacity factors. If there's no wind in summer and no insolation during winter you'll have to overbuild each by a factor of 5 or so and then build short-term storage on top of that. Conversely that means the bar to meet now is (renewables + storage) < fuel-based / 5. That's a rather fat margin. And things would be a lot cheaper overall if we could shave that off with some long-term storage.
  - deeviant 6y ago
    > If there's no wind in summer and no insolation during winter you'll have to overbuild each by a factor of 5... If nuclear power physics stopped working October to March, that would drastically effect nuclear power economic competitiveness... Wait, what's this people are telling me, I can't just make stuff up? You make up a completely BS example but then actually go through and try to come out with actual numbers. Right.
    - deleted 6y ago
      [deleted]
    - manfredo 6y ago
      Windless days and cloud cover are phenomena that actually exist and are observed. The behavior of beta particles suddenly changing is not. Yes, 5x variability in wind production has actually been observed: https://en.wikipedia.org/wiki/File:Erie_Shores_Wind_Farm_output_Aug-Jul_2008.gif https://en.wikipedia.org/wiki/File:Erie_Shores_Wind_Farm_out... https://en.wikipedia.org/wiki/File:Windpowerprediction.png https://en.wikipedia.org/wiki/File:Windpowerprediction.png
      - deeviant 6y ago
        The statement was no X in Summer, no Y in winter. It was not talking about a daily or even weekly phenomena but seasonal one. There is no summer which have had no winds, no winters that have had no insolation or vice versa. Instead of making up numbers, you can use a site like this: https://www.solar-electric.com/learning-center/solar-insolation-maps.html/ https://www.solar-electric.com/learning-center/solar-insolat.... You'll find that by comparing seasonal best case to seasonal worst case it is something like, on average, 50% difference. It gets worse the closer you to get to the pole obviously. Furthermore, surplus production does not go into dev/null. Excess resources create markets, and there will be consumers that take advantage of cheaper surplus power (smelting, heavy industrial, desalination, hydrogen production, and whatever else anybody cooks up).
        the8472 6y ago
        > There is no summer which have had no winds, no winters that have had no insolation or vice versa. The part of "no production" were not meant to be taken literally. If you want a more precise statement then let me put it this way: For PV in central europe even an overcapacity factor of 5 would be insufficient to cover the difference between summer and winter. Germany's PV plants produced 7.3TWh during June 2019 and 0.58TWh during december 2018. Wind does look a bit better as far as seasonal differences go (about 4-5x) but it suffers from more short-term variability, so you might need less seasonal storage for it but it would require more medium-term (multi-day or -week) storage compared to solar which is a bit less variable during its peak months compared to wind's peak months.
  - sp332 6y ago
    It may be dramatic, but so far it's still a lot less money than building several months worth of batteries.
  - bryanlarsen 6y ago
    Running the numbers usually gives you numbers like 50% overbuild, but even if you're right, a 5x overbuild still is significantly cheaper than nuclear. A 5x overbuild would give you massive amounts of "free" electricity. I'm sure the world would find something economically useful to do with it. Maybe you could use it to generate green hydrocarbons from atmospheric CO2, killing several birds with one stone.
    - the8472 6y ago
      > Maybe you could use it to generate green hydrocarbons from atmospheric CO2 Which would start to look a lot like long-term storage. But subsidized by negative energy prices during excess production. So rather than bleeding money while someone else makes profits any power company will prefer to build less overcapacity (which also avoids risking devalued assets) and run their own peak-shaving if they can. Which means this problem still has to be solved one way or another. Whether you call it long-term storage or excess energy use.
    - HexagonalKitten 6y ago
      It isn't quite that easy though because it's night for all 5x at once, for instance. So you need to have transmission capacity for the 4x you don't use locally, to send it elsewhere when it is sunny, and to import 1x at night from your sunlit neighbors. > generate green hydrocarbons from atmospheric CO2, killing several birds with one stone. This is great because it means we can use guilt-free hydrocarbons where they're important. Like rocketry and airplanes, making lubricants, plastic bags, etc. > overbuild would give you massive amounts of "free" electricity. I'm sure the world would find something economically useful to do with it. Generating proofs of work for a blockchain collectible card game? :D
qwertox 6y ago
There is this concept of "Gravity Storage" [1] which could be promising, if some testing were to be done on it. Basically you cut a large cylinder out of the earth and lift it by pumping water below it. When you then need the energy, you release the water with the help of the weight of the cylinder and use it to generate electricity. It sounds a bit crazy, but it could be worth testing that approach, since it can also be used in a flat area like a desert. In any case, the company filed for insolvency this year [2]. There is a podcast episode [3] from "omega tau podcast" dedicated to it, which is worth listening to. [1]: https://heindl-energy.com/ https://heindl-energy.com/ [2]: https://heindl-energy.com/about-us/ https://heindl-energy.com/about-us/ [3]: https://omegataupodcast.net/299-gravity-storage/ https://omegataupodcast.net/299-gravity-storage/
- the8472 6y ago
  That is missing the point of my comment. I didn't say that no experimental technology exists. I said that no technology exists where we can point to a chart from which we can conclude that the technology will be ready and economical in a certain number of years if trends continue.
- dTal 6y ago
  The energy density of gravity storage is abysmal. How abysmal? A mobile phone battery can lift a 1-ton weight 10 meters.
BlueTemplar 6y ago
Iron-based storage seems promising... https://news.ycombinator.com/item?id=24996153 https://news.ycombinator.com/item?id=24996153
hedora 6y ago
Hydroelectric has been a viable form of seasonal storage for a while. Unfortunately, it stores energy when it’s rainy, and releases it when it’s sunny.

maxerickson 6y ago

Chemical storage (as methane or whatever) would work fine and the operational side would be more or less carbon neutral. The cost is high compared to burning fossil fuels, but we could do it as a society (have an excess of solar to meet household winter electrical needs and synthesize methane in the summer to use as household heat fuel in the winter). Just pulling numbers out of the darkness, the upfront cost here in a cold region would be ~¼ to ½ the cost of a house. High, but also clearly workable.

deeviant 6y ago

Seasonal storage? That's not a thing. You just scale your solar/wind installations to the part of the season with the least resource (solar and wind do not often have the same low point, either), which is economically feasible because it is cheaper than nuclear (and coal).

the8472 6y ago
That dramatically changes cost calculation. Currently "cheaper than X" models don't account for such overcapacity factors. If there's no wind in summer and no insolation during winter you'll have to overbuild each by a factor of 5 or so and then build short-term storage on top of that. Conversely that means the bar to meet now is (renewables + storage) < fuel-based / 5. That's a rather fat margin. And things would be a lot cheaper overall if we could shave that off with some long-term storage.
- deeviant 6y ago
  > If there's no wind in summer and no insolation during winter you'll have to overbuild each by a factor of 5... If nuclear power physics stopped working October to March, that would drastically effect nuclear power economic competitiveness... Wait, what's this people are telling me, I can't just make stuff up? You make up a completely BS example but then actually go through and try to come out with actual numbers. Right.
  - deleted 6y ago
    [deleted]
  - manfredo 6y ago
    Windless days and cloud cover are phenomena that actually exist and are observed. The behavior of beta particles suddenly changing is not. Yes, 5x variability in wind production has actually been observed: https://en.wikipedia.org/wiki/File:Erie_Shores_Wind_Farm_output_Aug-Jul_2008.gif https://en.wikipedia.org/wiki/File:Erie_Shores_Wind_Farm_out... https://en.wikipedia.org/wiki/File:Windpowerprediction.png https://en.wikipedia.org/wiki/File:Windpowerprediction.png
    - deeviant 6y ago
      The statement was no X in Summer, no Y in winter. It was not talking about a daily or even weekly phenomena but seasonal one. There is no summer which have had no winds, no winters that have had no insolation or vice versa. Instead of making up numbers, you can use a site like this: https://www.solar-electric.com/learning-center/solar-insolation-maps.html/ https://www.solar-electric.com/learning-center/solar-insolat.... You'll find that by comparing seasonal best case to seasonal worst case it is something like, on average, 50% difference. It gets worse the closer you to get to the pole obviously. Furthermore, surplus production does not go into dev/null. Excess resources create markets, and there will be consumers that take advantage of cheaper surplus power (smelting, heavy industrial, desalination, hydrogen production, and whatever else anybody cooks up).
      - the8472 6y ago
        > There is no summer which have had no winds, no winters that have had no insolation or vice versa. The part of "no production" were not meant to be taken literally. If you want a more precise statement then let me put it this way: For PV in central europe even an overcapacity factor of 5 would be insufficient to cover the difference between summer and winter. Germany's PV plants produced 7.3TWh during June 2019 and 0.58TWh during december 2018. Wind does look a bit better as far as seasonal differences go (about 4-5x) but it suffers from more short-term variability, so you might need less seasonal storage for it but it would require more medium-term (multi-day or -week) storage compared to solar which is a bit less variable during its peak months compared to wind's peak months.
- sp332 6y ago
  It may be dramatic, but so far it's still a lot less money than building several months worth of batteries.
- bryanlarsen 6y ago
  Running the numbers usually gives you numbers like 50% overbuild, but even if you're right, a 5x overbuild still is significantly cheaper than nuclear. A 5x overbuild would give you massive amounts of "free" electricity. I'm sure the world would find something economically useful to do with it. Maybe you could use it to generate green hydrocarbons from atmospheric CO2, killing several birds with one stone.
  - the8472 6y ago
    > Maybe you could use it to generate green hydrocarbons from atmospheric CO2 Which would start to look a lot like long-term storage. But subsidized by negative energy prices during excess production. So rather than bleeding money while someone else makes profits any power company will prefer to build less overcapacity (which also avoids risking devalued assets) and run their own peak-shaving if they can. Which means this problem still has to be solved one way or another. Whether you call it long-term storage or excess energy use.
  - HexagonalKitten 6y ago
    It isn't quite that easy though because it's night for all 5x at once, for instance. So you need to have transmission capacity for the 4x you don't use locally, to send it elsewhere when it is sunny, and to import 1x at night from your sunlit neighbors. > generate green hydrocarbons from atmospheric CO2, killing several birds with one stone. This is great because it means we can use guilt-free hydrocarbons where they're important. Like rocketry and airplanes, making lubricants, plastic bags, etc. > overbuild would give you massive amounts of "free" electricity. I'm sure the world would find something economically useful to do with it. Generating proofs of work for a blockchain collectible card game? :D

qwertox 6y ago

There is this concept of "Gravity Storage" [1] which could be promising, if some testing were to be done on it. Basically you cut a large cylinder out of the earth and lift it by pumping water below it. When you then need the energy, you release the water with the help of the weight of the cylinder and use it to generate electricity. It sounds a bit crazy, but it could be worth testing that approach, since it can also be used in a flat area like a desert. In any case, the company filed for insolvency this year [2]. There is a podcast episode [3] from "omega tau podcast" dedicated to it, which is worth listening to. [1]: https://heindl-energy.com/ https://heindl-energy.com/ [2]: https://heindl-energy.com/about-us/ https://heindl-energy.com/about-us/ [3]: https://omegataupodcast.net/299-gravity-storage/ https://omegataupodcast.net/299-gravity-storage/

the8472 6y ago
That is missing the point of my comment. I didn't say that no experimental technology exists. I said that no technology exists where we can point to a chart from which we can conclude that the technology will be ready and economical in a certain number of years if trends continue.
dTal 6y ago
The energy density of gravity storage is abysmal. How abysmal? A mobile phone battery can lift a 1-ton weight 10 meters.

BlueTemplar 6y ago

Iron-based storage seems promising... https://news.ycombinator.com/item?id=24996153 https://news.ycombinator.com/item?id=24996153

hedora 6y ago

Hydroelectric has been a viable form of seasonal storage for a while. Unfortunately, it stores energy when it’s rainy, and releases it when it’s sunny.