5 ms·

Lets put down some Swedish numbers. During the coldest winter month, solar energy produce (as per statistics from the solar industry in Sweden) somewhere aroun

by belorn 6mo ago

Lets put down some Swedish numbers. During the coldest winter month, solar energy produce (as per statistics from the solar industry in Sweden) somewhere around 3-7% of the amount produced during the warmest month. Households also consume around 2-4 times the amount of energy during the coldest month compared to the warmest month. Sweden is a country where only a small minority have air conditioning installed at home. Those are the worst month vs the best month. Overall the winter is not that bad, but it is still pretty bad for solar. Talking with people who has had solar installed here, the general story is very similar. During periods where it do produce the market price is already exceptional low, so it isn't returning a major saving. When the market price is high, the output is low, forcing them to be connected to the grid and pay whatever the electrical company demand during the highest market peaks, as well as taxes and grid fees which themselves has increased to match the cost of high variability. All this looks very different in countries with much warmer climates and where the major energy consumption from households are air conditioning.

gpm 6mo ago
Yeah but: 1. Sweden is just about the worst case, there's very few countries/people that far north. 2. There's this genius invention called "wires". HVDC has transmission losses on the order of 3.5% per 1,000km. You don't have to colocate the solar.
- buzer 6mo ago
  You don't need to colocate the solar, but you need to make sure you can get that power when you actually need it. During crisis nations are going to restrict exporting electricity and prioritizing their own residents. Electricity that is generated in Germany is not going to warm up Nordic countries if Germany doesn't let it. Wires are also susceptible to sabotage, especially undersea ones (which are the current major connection points to Europe).
  - hardlianotion 6mo ago
    The issue is more the other way at the moment. Norwegian prices can get high as they are exposed to German demand over the interconnector.
    - buzer 6mo ago
      Sure, that is the current situation but if the Nordic countries started relying on solar from central Europe (especially Finland since it doesn't have the hydro capacity Norway & Sweden have) things could get ugly during crisis. The GP essentially framed overprovisioned solar as solution to anyone who might rely on nuclear without taking in account realities in many countries.
- belorn 6mo ago
  Wires and HVDC transmissions are nice, but they have a fairly large downside. They are major infrastructure projects that cost a lot of money and they don't produce any energy. Adding that cost to the solar panels makes them significantly more expensive, and solar/wind farms owners are not exactly willing to bear that cost.
- AnthonyMouse 6mo ago
  > Sweden is just about the worst case, there's very few countries/people that far north. Sweden is worse but it's still a significant issue in e.g. New York or Paris or Auckland. > There's genius invention called "wires". HVDC has transmission losses on the order of 3.5% per 1,000km. You don't have to colocate the solar. It's more than 1000km from the places that get cold to a part of the world where it isn't winter. Suppose we ignore that it's winter in the US Northeast and Southeast at the same time and run HVDC 2000+ km to Florida because it gets an extra hour of sunlight. Long distance transmission can't be used to counter seasonal output and regional weather at the same time because one requires the generation to be spread everywhere and the other requires it to be concentrated closer to the equator. If we concentrate the solar in Florida to mitigate winter in New England then we're screwed when Florida is overcast.
  - gpm 6mo ago
    > it's still a significant issue in e.g. New York or Paris or Auckland. No it isn't. Wires still might be worth it, but these are all close enough to the equator that you can just over provision locally without issue if you prefer. > It's more than 1000km from the places that get cold Solar panels work better in the cold. The issue is with how far from the equator Sweden is, not how cold it is.
    - AnthonyMouse 6mo ago
      > No it isn't. In the US Northeast solar generates around four times as much in July as December. This is sufficiently bad when what you need is more power in the winter. Paris is a little worse. Sweden is significantly worse. > Wires still might be worth it, but these are all close enough to the equator that you can just over provision locally without issue if you prefer. If I need 25% more output in the month when solar has 75% less output, how much do I have to over-provision? > Solar panels work better in the cold. Places that need more electricity in the winter because they're cold are cold in the winter because they're further away from the equator.
      - gpm 6mo ago
- nnevod 6mo ago
  HVDC (and even the grid in general) doesn't transmit all that much power. The largest currently existing line - Changji-Guquan UHVDC link in China - transmits 12GW. It's significantly more than what an average long-range link of current grids transmits, yes. But is it a lot? Looking from consumption side, my home city of ~1 million people has several coal-fired plants, producing 1.5 GW of electricity and about 5GW of heating. Plus an hydropower station producing 6 GW. Most of that is consumed by an aluminium plant, but nonetheless, it's also part of the city. So that's roughly 12GW on a cold winter day (I suppose we do want to make heating cleaner as well), and probably 6 GW in summer. Heat pumps could be used to reduce power consumed by heating, but even the air-source pumps are not cheap, and they don't provide much efficiency gain in the cold. Ground-source pumps are extremely expensive and reqiure heat replenishment or the ground will freeze - such is the balance here. So, the world's largest link to power just one city, out of tens of them. It quickly gets prohibitively expensive. The only realictic answer, it seems, is annual-scale storage. I hope that "dirt pile storage" works well enough and succeeds, batteries are just too expensive and material hungry, hydrogen is problematic to store well either and we don't seem to have good enough scalable direct carbon capture to synthesize methane or propane.
kalleboo 6mo ago
The nice thing is Sweden has lots of hydro, which works as natural long-term energy storage. Every bit of solar you generate means water is kept in the dam for use later in the year. You also can't ignore wind power which should be part of any plan to "overbuild".
- mastermage 6mo ago
  All of the discussions here conveniently ignore the existance of Wind. Which fortunately has higher yield in the months when there is less sun.
  - TheOtherHobbes 6mo ago
    Yes, it's a mix. It's always a mix. Arguing that "renewables" = "solar" is a classic straw man. So is comparing rooftop solar for a single property to grid solar for a country to a continent-sized grid of mixed renewable sources. Battery and storage tech are barely getting started. Pumped storage is perfectly capable of smoothing out seasonal loads. There's some capex for physical pumped storage - less than for a nuke plant - but once running it's comparatively low cost.
    - fi358 6mo ago
      I think the amount of energy needed during wintertime would be difficult to cover with pumped storage or traditional batteries. You have to have suitable geography for pumped storage and also enough (fresh) water available for that. However, instead of water compressed air could be also used, but that has also problems.
- mpweiher 6mo ago
  So why are the Swedes investing heavily in nuclear energy again, after nixing the nuclear exit they had on the books?
  - ViewTrick1002 6mo ago
    Sweden isn't investing in nuclear power. The current right wing government is creating a culture war issue while not wanting to accept the costs, nor creating a deal that will survive through elections by creating a more comprehensive coalition backing it. They've moved "We'll start building this electory cycle!!" to "large scale reactors" to "SMRs!!" to now targetting the final investment decision in 2029. The latest step in the saga is the state owned power company refusing to get their credit rating tarnished by being too involved in the nuclear project. The latest move is them owning 20%, the industry owning 20% and the government owning 60%. The industry still haven't comitted to their 20% due to the absolutely stupid costs involved. With the government as a first negotiation move stepping in with a direct handout of €3B. On top of credit and construction guarantees, a CFD and adjusting it all depending on how costly the build is to guarantee a profit. But it is quite easy to understand why. Taking what one of the nuclear reactors earns in Sweden and then applying solely the interest from a new build leads to a loss of ~€1.5B per year. Then you also need to run, fuel and maintain the plant.
grey-area 6mo ago
Scotland at a similar latitude to the populated parts of Sweden has hit 100% renewables generation in the past and will do so again. Renewables are not just solar and hydro storage is also suitable. You are also ignoring that improving housing stock with good insulation is a much better answer to excessive energy use in winter than attempting to find more supply in winter.

by belorn 6mo ago

gpm 6mo ago

Yeah but: 1. Sweden is just about the worst case, there's very few countries/people that far north. 2. There's this genius invention called "wires". HVDC has transmission losses on the order of 3.5% per 1,000km. You don't have to colocate the solar.

buzer 6mo ago
You don't need to colocate the solar, but you need to make sure you can get that power when you actually need it. During crisis nations are going to restrict exporting electricity and prioritizing their own residents. Electricity that is generated in Germany is not going to warm up Nordic countries if Germany doesn't let it. Wires are also susceptible to sabotage, especially undersea ones (which are the current major connection points to Europe).
- hardlianotion 6mo ago
  The issue is more the other way at the moment. Norwegian prices can get high as they are exposed to German demand over the interconnector.
  - buzer 6mo ago
    Sure, that is the current situation but if the Nordic countries started relying on solar from central Europe (especially Finland since it doesn't have the hydro capacity Norway & Sweden have) things could get ugly during crisis. The GP essentially framed overprovisioned solar as solution to anyone who might rely on nuclear without taking in account realities in many countries.
belorn 6mo ago
Wires and HVDC transmissions are nice, but they have a fairly large downside. They are major infrastructure projects that cost a lot of money and they don't produce any energy. Adding that cost to the solar panels makes them significantly more expensive, and solar/wind farms owners are not exactly willing to bear that cost.
AnthonyMouse 6mo ago
> Sweden is just about the worst case, there's very few countries/people that far north. Sweden is worse but it's still a significant issue in e.g. New York or Paris or Auckland. > There's genius invention called "wires". HVDC has transmission losses on the order of 3.5% per 1,000km. You don't have to colocate the solar. It's more than 1000km from the places that get cold to a part of the world where it isn't winter. Suppose we ignore that it's winter in the US Northeast and Southeast at the same time and run HVDC 2000+ km to Florida because it gets an extra hour of sunlight. Long distance transmission can't be used to counter seasonal output and regional weather at the same time because one requires the generation to be spread everywhere and the other requires it to be concentrated closer to the equator. If we concentrate the solar in Florida to mitigate winter in New England then we're screwed when Florida is overcast.
- gpm 6mo ago
  > it's still a significant issue in e.g. New York or Paris or Auckland. No it isn't. Wires still might be worth it, but these are all close enough to the equator that you can just over provision locally without issue if you prefer. > It's more than 1000km from the places that get cold Solar panels work better in the cold. The issue is with how far from the equator Sweden is, not how cold it is.
  - AnthonyMouse 6mo ago
    > No it isn't. In the US Northeast solar generates around four times as much in July as December. This is sufficiently bad when what you need is more power in the winter. Paris is a little worse. Sweden is significantly worse. > Wires still might be worth it, but these are all close enough to the equator that you can just over provision locally without issue if you prefer. If I need 25% more output in the month when solar has 75% less output, how much do I have to over-provision? > Solar panels work better in the cold. Places that need more electricity in the winter because they're cold are cold in the winter because they're further away from the equator.
    - gpm 6mo ago
nnevod 6mo ago
HVDC (and even the grid in general) doesn't transmit all that much power. The largest currently existing line - Changji-Guquan UHVDC link in China - transmits 12GW. It's significantly more than what an average long-range link of current grids transmits, yes. But is it a lot? Looking from consumption side, my home city of ~1 million people has several coal-fired plants, producing 1.5 GW of electricity and about 5GW of heating. Plus an hydropower station producing 6 GW. Most of that is consumed by an aluminium plant, but nonetheless, it's also part of the city. So that's roughly 12GW on a cold winter day (I suppose we do want to make heating cleaner as well), and probably 6 GW in summer. Heat pumps could be used to reduce power consumed by heating, but even the air-source pumps are not cheap, and they don't provide much efficiency gain in the cold. Ground-source pumps are extremely expensive and reqiure heat replenishment or the ground will freeze - such is the balance here. So, the world's largest link to power just one city, out of tens of them. It quickly gets prohibitively expensive. The only realictic answer, it seems, is annual-scale storage. I hope that "dirt pile storage" works well enough and succeeds, batteries are just too expensive and material hungry, hydrogen is problematic to store well either and we don't seem to have good enough scalable direct carbon capture to synthesize methane or propane.

kalleboo 6mo ago

The nice thing is Sweden has lots of hydro, which works as natural long-term energy storage. Every bit of solar you generate means water is kept in the dam for use later in the year. You also can't ignore wind power which should be part of any plan to "overbuild".

mastermage 6mo ago
All of the discussions here conveniently ignore the existance of Wind. Which fortunately has higher yield in the months when there is less sun.
- TheOtherHobbes 6mo ago
  Yes, it's a mix. It's always a mix. Arguing that "renewables" = "solar" is a classic straw man. So is comparing rooftop solar for a single property to grid solar for a country to a continent-sized grid of mixed renewable sources. Battery and storage tech are barely getting started. Pumped storage is perfectly capable of smoothing out seasonal loads. There's some capex for physical pumped storage - less than for a nuke plant - but once running it's comparatively low cost.
  - fi358 6mo ago
    I think the amount of energy needed during wintertime would be difficult to cover with pumped storage or traditional batteries. You have to have suitable geography for pumped storage and also enough (fresh) water available for that. However, instead of water compressed air could be also used, but that has also problems.
mpweiher 6mo ago
So why are the Swedes investing heavily in nuclear energy again, after nixing the nuclear exit they had on the books?
- ViewTrick1002 6mo ago
  Sweden isn't investing in nuclear power. The current right wing government is creating a culture war issue while not wanting to accept the costs, nor creating a deal that will survive through elections by creating a more comprehensive coalition backing it. They've moved "We'll start building this electory cycle!!" to "large scale reactors" to "SMRs!!" to now targetting the final investment decision in 2029. The latest step in the saga is the state owned power company refusing to get their credit rating tarnished by being too involved in the nuclear project. The latest move is them owning 20%, the industry owning 20% and the government owning 60%. The industry still haven't comitted to their 20% due to the absolutely stupid costs involved. With the government as a first negotiation move stepping in with a direct handout of €3B. On top of credit and construction guarantees, a CFD and adjusting it all depending on how costly the build is to guarantee a profit. But it is quite easy to understand why. Taking what one of the nuclear reactors earns in Sweden and then applying solely the interest from a new build leads to a loss of ~€1.5B per year. Then you also need to run, fuel and maintain the plant.

grey-area 6mo ago

Scotland at a similar latitude to the populated parts of Sweden has hit 100% renewables generation in the past and will do so again. Renewables are not just solar and hydro storage is also suitable. You are also ignoring that improving housing stock with good insulation is a much better answer to excessive energy use in winter than attempting to find more supply in winter.