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As a Spaniard myself that have lived in several cities in Germany like Hamburg, I will tell you a secret: There is no sun in Germany. My eyes have to adapt to t

As a Spaniard myself that have lived in several cities in Germany like Hamburg, I will tell you a secret: There is no sun in Germany. My eyes have to adapt to the luminosity change every time I go to southern Europe or north of Africa. I have always believed that putting solar panels in Germany was a wrong solution. I have also lived in Argentina and travelled to Uruguay. Those countries have a massive amount of natural resources compared with Germany for a population that is much smaller.

blkhawk 3y ago
yes, but panels can be made cheap enough and there is plenty of surfaces you can plaster them on. To just put them on roofs was very much the right choice compared to say Desertec. When you look into it then Desertec would have been a huge waste of resources. The issue at this point is not generation - its storage and to a lesser degree transport.
audunw 3y ago
Your personal impression doesn't really matter though. What matters is the statistics. Of course there is sun in Germany. Yes, there's less. But then it's also cooler which makes the solar panels more efficient. What matters is if it's economical to use solar panels there, which it is. In summer, where some areas will use quite a bit of AC, there's more daylight hours than regions further south. In winter, if you have vertically mounted panels, a nice effect you can get is that the snow reflects extra sunlight from the ground to the solar panel. Fun fact, even the airport in Longyearbyen in Svalbard, Norway - an island close to the north pole - has solar panels. They're mounted vertically on the walls, since the sun is never very high in the sky. There's no sun at all in winter, but in summer there's sun 24/7. https://sunpower.maxeon.com/int/case-study/energy-arctic-circle-moving-coal-solar https://sunpower.maxeon.com/int/case-study/energy-arctic-cir... It's surprising how much production they get even that far north: "the PV system produces as much as 70 percent of what is typically produced in Germany" So please don't use your subjective impression about how bright you feel it is to gauge the viability of solar. I can tell you from personal experience, it's not very bright in Svalbard even in summer. BTW, much of the energy need in winter in northern climates is for heating. It's surprisingly effective to store thermal energy over several months. So it's actually viable to dump heat from excess solar in a thermal reservoir in summer, and use that heat in winter.
- rolisz 3y ago
  > It's surprisingly effective to store thermal energy over several months. Do tell more.
  - nimeni 3y ago
    For example, this project [1] in Finland will provide 200 MW of district heating and can store 90 GWh. Cost estimate was 109M EUR in 2021 [2]. [1]: https://www.vantaanenergia.fi/en/we/carbon-negativity-2030/heatstorage/ https://www.vantaanenergia.fi/en/we/carbon-negativity-2030/h... [2]: https://tem.fi/paatos?decisionId=0900908f8077a0e8 https://tem.fi/paatos?decisionId=0900908f8077a0e8
    - rolisz 3y ago
      Interesting. We'll see in 2026 when it's finished how much it actually costs and how well it actually works :)
    - AnonymousPlanet 3y ago
      Cool, so you would only need about 120 of those to compensate Germany's current wind and solar power in the gaps without wind and sun. That's just 1.3 billion Euros. That's better than the last time I checked out heat storage. Then it was 100MWh for roughly a football stadium sized area with subterranean sand.
- AnonymousPlanet 3y ago
  > It's surprisingly effective to store thermal energy over several months. And how much would you need? Have you done the maths on this? I did. There are plenty of times in e.g. November when neither wind nor solar are good for much (production drops to like 1-2% of the average). That goes on for weeks. Just trying to compensate those losses for two weeks for the current amount of wind and solar Germany has, takes > 10 TWh of storage. How much thermal storage do you think would we need to build to get that? I made those calculations to get an idea how much storage we would need to be able to finally shut down power stations running on coal or gas. I was quite shocked about the number. Whenever someone points out the realities of things some people are quick to counter with some utopian ideas, but usually they don't do the math on it. I encourage you to always make a calculation, at least on a napkin, to get an idea of the magnitude of what would be required. Your comment reads like it would be as easy as the flick of a wrist because something "is surprisingly effective". It's not. It takes the amount of many, many Stuttgart 21s in dedication, costs and time.
pydry 3y ago
You can kind of tell when it's sunny or windy in European countries. If it's windy renewables skeptics will tell you how little power is being generated right now by solar panels. If it's sunny renewables skeptics will tell you how little power is generated by wind turbines right now. This is partly because skeptics are gonna skeptic but also it's also because sun and wind anticorrelate way more than most people think, reducing storage requirements down to quite reasonable levels (such that pumped storage/hydrogen can economically satisfy most grids). citation: https://reneweconomy.com.au/a-near-100-per-cent-renewables-grid-is-well-within-reach-and-with-little-storage/ https://reneweconomy.com.au/a-near-100-per-cent-renewables-g...
- closewith 3y ago
  Citation needed for that last claim, as it's patently absurd.
  - pydry 3y ago
    [flagged]
    - abduhl 3y ago
      I have no horse in this race but just wanted to point out the absurdity of this methodology: “The generation data for wind, rooftop and utility solar data was rescaled to supply ~60%, 25% and 20% of demand respectively over the year. For example, over the last year utility solar generation has met 5% of demand. The target for utility solar was 20%, so I rescaled the last 7 days of utility solar data by 4x (ie, 20% divided by 5%).”
      - ZeroGravitas 3y ago
        That's a perfectly sensible methodology, do you have a specific problem with it? "Wind and Solar are fine as long as they're only X% of the grid, but you'd need <silly amount> of storage for lulls in wind and sun once they get close to 100%" is the question it's answering.
KaiserPro 3y ago
I live in the UK. It rains here. however with a 5kw array, and a 13kwh battery, we are self sufficient for at least 6 months of the year (as in 0kw from grid) and at worst 40% in the midst of winter. Today I have generated 10kwhr and its only 14:00. Germany should have no real issues with solar production. I mean its not great, but its not anywhere near as bad as you imply.
- Izkata 3y ago
  > I live in the UK. > It rains here. Funny thought popped into my head: Rain-based water wheel.

blkhawk 3y ago

yes, but panels can be made cheap enough and there is plenty of surfaces you can plaster them on. To just put them on roofs was very much the right choice compared to say Desertec. When you look into it then Desertec would have been a huge waste of resources. The issue at this point is not generation - its storage and to a lesser degree transport.

audunw 3y ago

Your personal impression doesn't really matter though. What matters is the statistics. Of course there is sun in Germany. Yes, there's less. But then it's also cooler which makes the solar panels more efficient. What matters is if it's economical to use solar panels there, which it is. In summer, where some areas will use quite a bit of AC, there's more daylight hours than regions further south. In winter, if you have vertically mounted panels, a nice effect you can get is that the snow reflects extra sunlight from the ground to the solar panel. Fun fact, even the airport in Longyearbyen in Svalbard, Norway - an island close to the north pole - has solar panels. They're mounted vertically on the walls, since the sun is never very high in the sky. There's no sun at all in winter, but in summer there's sun 24/7. https://sunpower.maxeon.com/int/case-study/energy-arctic-circle-moving-coal-solar https://sunpower.maxeon.com/int/case-study/energy-arctic-cir... It's surprising how much production they get even that far north: "the PV system produces as much as 70 percent of what is typically produced in Germany" So please don't use your subjective impression about how bright you feel it is to gauge the viability of solar. I can tell you from personal experience, it's not very bright in Svalbard even in summer. BTW, much of the energy need in winter in northern climates is for heating. It's surprisingly effective to store thermal energy over several months. So it's actually viable to dump heat from excess solar in a thermal reservoir in summer, and use that heat in winter.

rolisz 3y ago
> It's surprisingly effective to store thermal energy over several months. Do tell more.
- nimeni 3y ago
  For example, this project [1] in Finland will provide 200 MW of district heating and can store 90 GWh. Cost estimate was 109M EUR in 2021 [2]. [1]: https://www.vantaanenergia.fi/en/we/carbon-negativity-2030/heatstorage/ https://www.vantaanenergia.fi/en/we/carbon-negativity-2030/h... [2]: https://tem.fi/paatos?decisionId=0900908f8077a0e8 https://tem.fi/paatos?decisionId=0900908f8077a0e8
  - rolisz 3y ago
    Interesting. We'll see in 2026 when it's finished how much it actually costs and how well it actually works :)
  - AnonymousPlanet 3y ago
    Cool, so you would only need about 120 of those to compensate Germany's current wind and solar power in the gaps without wind and sun. That's just 1.3 billion Euros. That's better than the last time I checked out heat storage. Then it was 100MWh for roughly a football stadium sized area with subterranean sand.
AnonymousPlanet 3y ago
> It's surprisingly effective to store thermal energy over several months. And how much would you need? Have you done the maths on this? I did. There are plenty of times in e.g. November when neither wind nor solar are good for much (production drops to like 1-2% of the average). That goes on for weeks. Just trying to compensate those losses for two weeks for the current amount of wind and solar Germany has, takes > 10 TWh of storage. How much thermal storage do you think would we need to build to get that? I made those calculations to get an idea how much storage we would need to be able to finally shut down power stations running on coal or gas. I was quite shocked about the number. Whenever someone points out the realities of things some people are quick to counter with some utopian ideas, but usually they don't do the math on it. I encourage you to always make a calculation, at least on a napkin, to get an idea of the magnitude of what would be required. Your comment reads like it would be as easy as the flick of a wrist because something "is surprisingly effective". It's not. It takes the amount of many, many Stuttgart 21s in dedication, costs and time.

pydry 3y ago

You can kind of tell when it's sunny or windy in European countries. If it's windy renewables skeptics will tell you how little power is being generated right now by solar panels. If it's sunny renewables skeptics will tell you how little power is generated by wind turbines right now. This is partly because skeptics are gonna skeptic but also it's also because sun and wind anticorrelate way more than most people think, reducing storage requirements down to quite reasonable levels (such that pumped storage/hydrogen can economically satisfy most grids). citation: https://reneweconomy.com.au/a-near-100-per-cent-renewables-grid-is-well-within-reach-and-with-little-storage/ https://reneweconomy.com.au/a-near-100-per-cent-renewables-g...

closewith 3y ago
Citation needed for that last claim, as it's patently absurd.
- pydry 3y ago
  [flagged]
  - abduhl 3y ago
    I have no horse in this race but just wanted to point out the absurdity of this methodology: “The generation data for wind, rooftop and utility solar data was rescaled to supply ~60%, 25% and 20% of demand respectively over the year. For example, over the last year utility solar generation has met 5% of demand. The target for utility solar was 20%, so I rescaled the last 7 days of utility solar data by 4x (ie, 20% divided by 5%).”
    - ZeroGravitas 3y ago
      That's a perfectly sensible methodology, do you have a specific problem with it? "Wind and Solar are fine as long as they're only X% of the grid, but you'd need <silly amount> of storage for lulls in wind and sun once they get close to 100%" is the question it's answering.

KaiserPro 3y ago

I live in the UK. It rains here. however with a 5kw array, and a 13kwh battery, we are self sufficient for at least 6 months of the year (as in 0kw from grid) and at worst 40% in the midst of winter. Today I have generated 10kwhr and its only 14:00. Germany should have no real issues with solar production. I mean its not great, but its not anywhere near as bad as you imply.

Izkata 3y ago
> I live in the UK. > It rains here. Funny thought popped into my head: Rain-based water wheel.