6 ms·

How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Renewable optimists consistently under-estimate the storage

How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Renewable optimists consistently under-estimate the storage problem by orders of magnitude. We don't have enough batteries on Earth to hold one single day's worth of electricity. And for us to actually rely on solar, we would need to store multiple months of electricity to survive the winter. Solar is cheap because you're comparing a generation source that works on occasion with a generation source that works 24/7. I'm not anti-solar at all. But I am realistic about what we can and can't do with it. The thing that will make a solar grid practical _today_ is focusing on variable loads. When the sun is shining, we should be cranking the AC of every home and office, smelting aluminum, filling dams, etc.

delecti 3y ago
The comment didn't say "90% solar", it said "90% renewables". That includes hydro and wind, which don't stop at night or in the winter.
- tmikaeld 3y ago
  Current and near-future grid cannot handle such a balance of renewables, especially hydro takes a lot of beating when the water level goes up and down constantly.
  - delecti 3y ago
    Nobody is blind to the fact that the grid will need to be updated to be more flexible.
- ekianjo 3y ago
  Thats a myth. You cannot have baseline power with renewables only throughout the year. Hydro only works in very specific places and the same for wind.
  - dale_glass 3y ago
    Why? Build more. Interconnect with HVDC.
  - pfdietz 3y ago
    Yes, you may need various kinds of storage as well, filled by renewables. E-fuels can be used to shift energy across seasons.
- concordDance 3y ago
  https://gridwatch.templar.co.uk/ https://gridwatch.templar.co.uk/ Wind can be very low for days and low for weeks. Hydro is ecologically devastating and there aren't enough sites for it.
  - awestroke 3y ago
    Unlike oil and coal which are very ecologically beneficial?
    - deleted 3y ago
      [deleted]
    - ComputerGuru 3y ago
      That's not a fair reply at all. If we don't care about the ecology, then we might as well just continue to use petroleum!
      - awestroke 3y ago
        Ecosystem damage from hydro is local, ecosystem from fossil fuel is global. We are heading for extinction as a species, and under such circumstances it makes sense to cause local ecosystem damage in the form of flooding.
        ComputerGuru 3y ago
        > We are heading for extinction as a species, and under such circumstances [...] We absolutely are not headed towards extinction as a species. We are like cockroaches and the human species will survive. Using "oh no, the human race is dying out altogether and we must preserve it all costs" is a ridiculous argument. > [..] it makes sense to cause local ecosystem damage in the form of flooding. It isn't just the (risk of) flooding. It's hubris to believe we can actually foresee all the second-order ramifications from such large-scale terraforming projects. (Hydroelectric) dams have devastated the local wildlife, transformed the surrounding permaculture for the worse, and set off horrible chain reactions with devastating consequences for the local flora and fauna which have global ramifications down the line, as we are discovering today. Nothing happens in a bubble. This same argument was once made of fossil fuel emissions (when we thought that smog in the biggest industrial cities was our biggest problem and outsourcing them to developing nations was a great win-win /s). That obviously wasn't true. Why would you wish to repeat the same mistake?
deleted 3y ago
[deleted]
NickC25 3y ago
>How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Maybe not the national grid, but there are plenty of places in the US where the sun shines a lot more than 40% of the day during the winter. Start there. If Southern CA, AZ, NM, TX, FL, etc.. which all get a ton of sun no matter the season can reduce their reliance on the federal grid, that's a hell of a start, and we should be celebrating that as a great first step and building off of that. I thought the whole point of alternative energy sources is acknowledging that certain locales have potential for different energy sources (solar, hydroelectric, wind, etc..) and we should as a society should take full advantage of that? We know oil isn't going away any time soon, but why aren't we saying "oh City XYZ or State ABC is abundant in (alternative energy source), let's make use of that as best as we can"?
- Turing_Machine 3y ago
  > Maybe not the national grid, but there are plenty of places in the US where the sun shines a lot more than 40% of the day during the winter. It looks like Los Angeles only averages about 37% for the year as a whole, and Albuquerque averages about 38%, so I'm skeptical that there's anywhere that gets "a lot more than 40%" in winter. You have to take clouds into account as well, remember. Cloudy days exist even in desert areas. https://en.wikipedia.org/wiki/List_of_cities_by_sunshine_duration https://en.wikipedia.org/wiki/List_of_cities_by_sunshine_dur...
  - PaulDavisThe1st 3y ago
    Thats 39% in ABQ of all hours in the year including night time. Nobody is pretending that solar can provide electricity via night time generation. That's what storage systems and alternative sources are for. The daylight story in ABQ is this: > "It is sunny 78.9% of daylight hours. The remaining 21.1% of daylight hours are likely cloudy or with shade, haze or low sun intensity. " http://www.albuquerque.climatemps.com/sunlight.php http://www.albuquerque.climatemps.com/sunlight.php
    - NickC25 3y ago
mordae 3y ago
Exactly! We have led seasonal lives for thousands of years. This is no biggie.
- matkoniecz 3y ago
  Brownouts and blackouts lasting for weeks during windless winter weeks are hardly solution. Trying to sell it as "no biggie" will not work well.
- dahfizz 3y ago
  Having heat in the winter is, in fact, a biggie.
croes 3y ago
>How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Where? Maybe we should try a more global approach to energy.
- concordDance 3y ago
  Long distance power transport is tricky for security reasons and also transmission losses (1% per 100 miles or so?).
- dahfizz 3y ago
  > Where? Almost the entire world? The sun is up for less than 9.5 hours in winter unless you are very close to the equator.[1][2][3][4] And that's assuming 0% cloud coverage. In reality, places like Germany only get an hour or two of real sunshine a day in the winter[5]. [1] https://www.timeanddate.com/sun/usa/new-york https://www.timeanddate.com/sun/usa/new-york [2] https://www.timeanddate.com/sun/usa/san-francisco https://www.timeanddate.com/sun/usa/san-francisco [3] https://www.timeanddate.com/sun/spain/madrid https://www.timeanddate.com/sun/spain/madrid [4] https://www.timeanddate.com/sun/china/beijing https://www.timeanddate.com/sun/china/beijing [5] https://www.statista.com/statistics/982758/average-sunshine-hours-germany/ https://www.statista.com/statistics/982758/average-sunshine-...
  - jmopp 3y ago
    The middle of winter in Europe, North America, and Asia is the middle of summer in South America, Southern Africa and Australia. Yes, global transmission of electricity is a problem. But the problem is not a global lack of sunshine.
    - SamPatt 3y ago
      Land - and thus population - is not evenly distributed across the globe, there is far more of both in the northern hemisphere. Global transmission of electricity isn't a "problem," it's non-existant.
- dotnet00 3y ago
cgeier 3y ago
There is an already pretty old (2013) study from Fraunhofer, which shows how 100% renewable energy in electric power and heating is possible in the medium term future (2050). Their ideas for storage are battery storage (52Gwh), pumped storage (60Gwh) and methane storage (86Twh) on the electric side. See [1] for a very short English description and [2] for the German original. [1] https://deepresource.wordpress.com/2017/09/16/blueprint-100-renewable-energy-base-for-germany/ https://deepresource.wordpress.com/2017/09/16/blueprint-100-... [2] https://www.ise.fraunhofer.de/de/veroeffentlichungen/studien/studie-energiesystem-deutschland-2050.html https://www.ise.fraunhofer.de/de/veroeffentlichungen/studien...
Sinidir 3y ago
You don't you build solar and wind, which have different seasonal productions. Wind power is actually higher during winter. See: https://www.researchgate.net/figure/Estimated-normalized-monthly-energy-gain-from-a-wind-turbine-together-with-the-normalized_fig3_320931692 https://www.researchgate.net/figure/Estimated-normalized-mon... And if you combine the graphs for solar and wind from this: https://aleasoft.com/european-solar-and-wind-energy-production-grew-year%E2%80%91on%E2%80%91year-in-october/ https://aleasoft.com/european-solar-and-wind-energy-producti... You can nicely see that they are complementary in terms of energy production.
mgfist 3y ago
It sounds like a problem at first glance but it isn't. For one, there's an easy solution: overbuild solar. With solar generation that is 2x-3x peak demand, you only need 4 hour storage to have a robust, clean grid with near 0 downtime. Add a bit of longer term storage and you've got a grid that's more reliable than the one today. That's the conceptually simple solution, but ofc there's more practical ones. Mix in wind, some nuclear, different storage solutions (Ev2grid, pumped hydro, rocks-in-a-box, etc..), demand-side solutions (VPPs), efficiency improvements (insulation, heatpumps), a few of the hundreds of advanced projects being researched (solar in space, enhanced geothermal, iron air batteries, SMRs, etc..). Combine the 1000s of solutions being proposed, researched and scaled out and you have a very solid plan of attack.
pfdietz 3y ago
You combine it with wind, batteries, and storage via an e-fuel like hydrogen. The latter is crucial. The cost of providing "synthetic baseload" in Germany doubles if you don't include it. See https://model.energy/ https://model.energy/ for optimization of an energy system using these to provide synthetic baseload, using various tweakable cost assumptions and historical weather data. The cost is not outrageous, likely well below new construction nuclear. In a place like India, you don't even need wind and hydrogen. PV and batteries will do just fine.

delecti 3y ago

The comment didn't say "90% solar", it said "90% renewables". That includes hydro and wind, which don't stop at night or in the winter.

tmikaeld 3y ago
Current and near-future grid cannot handle such a balance of renewables, especially hydro takes a lot of beating when the water level goes up and down constantly.
- delecti 3y ago
  Nobody is blind to the fact that the grid will need to be updated to be more flexible.
ekianjo 3y ago
Thats a myth. You cannot have baseline power with renewables only throughout the year. Hydro only works in very specific places and the same for wind.
- dale_glass 3y ago
  Why? Build more. Interconnect with HVDC.
- pfdietz 3y ago
  Yes, you may need various kinds of storage as well, filled by renewables. E-fuels can be used to shift energy across seasons.
concordDance 3y ago
https://gridwatch.templar.co.uk/ https://gridwatch.templar.co.uk/ Wind can be very low for days and low for weeks. Hydro is ecologically devastating and there aren't enough sites for it.
- awestroke 3y ago
  Unlike oil and coal which are very ecologically beneficial?
  - deleted 3y ago
    [deleted]
  - ComputerGuru 3y ago
    That's not a fair reply at all. If we don't care about the ecology, then we might as well just continue to use petroleum!
    - awestroke 3y ago
      Ecosystem damage from hydro is local, ecosystem from fossil fuel is global. We are heading for extinction as a species, and under such circumstances it makes sense to cause local ecosystem damage in the form of flooding.
      - ComputerGuru 3y ago
        > We are heading for extinction as a species, and under such circumstances [...] We absolutely are not headed towards extinction as a species. We are like cockroaches and the human species will survive. Using "oh no, the human race is dying out altogether and we must preserve it all costs" is a ridiculous argument. > [..] it makes sense to cause local ecosystem damage in the form of flooding. It isn't just the (risk of) flooding. It's hubris to believe we can actually foresee all the second-order ramifications from such large-scale terraforming projects. (Hydroelectric) dams have devastated the local wildlife, transformed the surrounding permaculture for the worse, and set off horrible chain reactions with devastating consequences for the local flora and fauna which have global ramifications down the line, as we are discovering today. Nothing happens in a bubble. This same argument was once made of fossil fuel emissions (when we thought that smog in the biggest industrial cities was our biggest problem and outsourcing them to developing nations was a great win-win /s). That obviously wasn't true. Why would you wish to repeat the same mistake?

deleted 3y ago

[deleted]

NickC25 3y ago

>How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Maybe not the national grid, but there are plenty of places in the US where the sun shines a lot more than 40% of the day during the winter. Start there. If Southern CA, AZ, NM, TX, FL, etc.. which all get a ton of sun no matter the season can reduce their reliance on the federal grid, that's a hell of a start, and we should be celebrating that as a great first step and building off of that. I thought the whole point of alternative energy sources is acknowledging that certain locales have potential for different energy sources (solar, hydroelectric, wind, etc..) and we should as a society should take full advantage of that? We know oil isn't going away any time soon, but why aren't we saying "oh City XYZ or State ABC is abundant in (alternative energy source), let's make use of that as best as we can"?

Turing_Machine 3y ago
> Maybe not the national grid, but there are plenty of places in the US where the sun shines a lot more than 40% of the day during the winter. It looks like Los Angeles only averages about 37% for the year as a whole, and Albuquerque averages about 38%, so I'm skeptical that there's anywhere that gets "a lot more than 40%" in winter. You have to take clouds into account as well, remember. Cloudy days exist even in desert areas. https://en.wikipedia.org/wiki/List_of_cities_by_sunshine_duration https://en.wikipedia.org/wiki/List_of_cities_by_sunshine_dur...
- PaulDavisThe1st 3y ago
  Thats 39% in ABQ of all hours in the year including night time. Nobody is pretending that solar can provide electricity via night time generation. That's what storage systems and alternative sources are for. The daylight story in ABQ is this: > "It is sunny 78.9% of daylight hours. The remaining 21.1% of daylight hours are likely cloudy or with shade, haze or low sun intensity. " http://www.albuquerque.climatemps.com/sunlight.php http://www.albuquerque.climatemps.com/sunlight.php
  - NickC25 3y ago

mordae 3y ago

Exactly! We have led seasonal lives for thousands of years. This is no biggie.

matkoniecz 3y ago
Brownouts and blackouts lasting for weeks during windless winter weeks are hardly solution. Trying to sell it as "no biggie" will not work well.
dahfizz 3y ago
Having heat in the winter is, in fact, a biggie.

croes 3y ago

>How do you power the grid with 90% solar when the sun only shines 40% of the day during the winter? Where? Maybe we should try a more global approach to energy.

concordDance 3y ago
Long distance power transport is tricky for security reasons and also transmission losses (1% per 100 miles or so?).
dahfizz 3y ago
> Where? Almost the entire world? The sun is up for less than 9.5 hours in winter unless you are very close to the equator.[1][2][3][4] And that's assuming 0% cloud coverage. In reality, places like Germany only get an hour or two of real sunshine a day in the winter[5]. [1] https://www.timeanddate.com/sun/usa/new-york https://www.timeanddate.com/sun/usa/new-york [2] https://www.timeanddate.com/sun/usa/san-francisco https://www.timeanddate.com/sun/usa/san-francisco [3] https://www.timeanddate.com/sun/spain/madrid https://www.timeanddate.com/sun/spain/madrid [4] https://www.timeanddate.com/sun/china/beijing https://www.timeanddate.com/sun/china/beijing [5] https://www.statista.com/statistics/982758/average-sunshine-hours-germany/ https://www.statista.com/statistics/982758/average-sunshine-...
- jmopp 3y ago
  The middle of winter in Europe, North America, and Asia is the middle of summer in South America, Southern Africa and Australia. Yes, global transmission of electricity is a problem. But the problem is not a global lack of sunshine.
  - SamPatt 3y ago
    Land - and thus population - is not evenly distributed across the globe, there is far more of both in the northern hemisphere. Global transmission of electricity isn't a "problem," it's non-existant.
dotnet00 3y ago

cgeier 3y ago

There is an already pretty old (2013) study from Fraunhofer, which shows how 100% renewable energy in electric power and heating is possible in the medium term future (2050). Their ideas for storage are battery storage (52Gwh), pumped storage (60Gwh) and methane storage (86Twh) on the electric side. See [1] for a very short English description and [2] for the German original. [1] https://deepresource.wordpress.com/2017/09/16/blueprint-100-renewable-energy-base-for-germany/ https://deepresource.wordpress.com/2017/09/16/blueprint-100-... [2] https://www.ise.fraunhofer.de/de/veroeffentlichungen/studien/studie-energiesystem-deutschland-2050.html https://www.ise.fraunhofer.de/de/veroeffentlichungen/studien...

Sinidir 3y ago

You don't you build solar and wind, which have different seasonal productions. Wind power is actually higher during winter. See: https://www.researchgate.net/figure/Estimated-normalized-monthly-energy-gain-from-a-wind-turbine-together-with-the-normalized_fig3_320931692 https://www.researchgate.net/figure/Estimated-normalized-mon... And if you combine the graphs for solar and wind from this: https://aleasoft.com/european-solar-and-wind-energy-production-grew-year%E2%80%91on%E2%80%91year-in-october/ https://aleasoft.com/european-solar-and-wind-energy-producti... You can nicely see that they are complementary in terms of energy production.

mgfist 3y ago

It sounds like a problem at first glance but it isn't. For one, there's an easy solution: overbuild solar. With solar generation that is 2x-3x peak demand, you only need 4 hour storage to have a robust, clean grid with near 0 downtime. Add a bit of longer term storage and you've got a grid that's more reliable than the one today. That's the conceptually simple solution, but ofc there's more practical ones. Mix in wind, some nuclear, different storage solutions (Ev2grid, pumped hydro, rocks-in-a-box, etc..), demand-side solutions (VPPs), efficiency improvements (insulation, heatpumps), a few of the hundreds of advanced projects being researched (solar in space, enhanced geothermal, iron air batteries, SMRs, etc..). Combine the 1000s of solutions being proposed, researched and scaled out and you have a very solid plan of attack.

pfdietz 3y ago

You combine it with wind, batteries, and storage via an e-fuel like hydrogen. The latter is crucial. The cost of providing "synthetic baseload" in Germany doubles if you don't include it. See https://model.energy/ https://model.energy/ for optimization of an energy system using these to provide synthetic baseload, using various tweakable cost assumptions and historical weather data. The cost is not outrageous, likely well below new construction nuclear. In a place like India, you don't even need wind and hydrogen. PV and batteries will do just fine.