5 ms·

How does solar work in the winter in northern latitudes?

totalview 4y ago
Alaskan here; it doesn’t work so hot in the winter months. Even if they are kept clear by maintenance workers (not that hard or expensive to hire someone to clear snow from a panel) the sun’s azimuth is so low in the winter that there is hardly any energy produced.
- fluoridation 4y ago
  Small correction: you mean altitude, not azimuth. Altitude is how far you need to tilt your head vertically to look at an object. Azimuth is the compass direction.
edent 4y ago
Pretty good. You can download several years of data from my domestic panels at https://shkspr.mobi/blog/2020/07/1800-days-of-minute-by-minute-solar-generation-data/ https://shkspr.mobi/blog/2020/07/1800-days-of-minute-by-minu... Sure, some days they'll be covered by snow. But in industrial systems that can easily be melted / brushed off. Obviously they don't generate as much in winter as in summer. But cool bright winter days are surprisingly plentiful.
Analemma_ 4y ago
Very well. Rooftop solar in Seattle pays for itself in 7-9 years, and we have the least sunlight and cheapest grid power of almost any place in the continental US.
- TedDoesntTalk 4y ago
  > Rooftop solar in Seattle pays for itself in 7-9 years Can you show me the arithmetic for that? I understand rooftop solar to cost $20,000 - $25,000. Is your non-solar electric bill over 7-9 years really more expensive than that? Seems impossible.
  - marssaxman 4y ago
    I'm afraid I don't have the exact numbers anymore, but I determined that the 2700W solar panel array installed on my Seattle house for about $14k in 2013 (including a new breaker panel) had paid for itself before the end of 2019. The system worked really well. People often think that solar won't work well in Seattle because it's cloudy so often, but light still comes in through the overcast, and solar panels don't care which angle the photons hit them from. Meanwhile, lower ambient temperatures mean the panels work more efficiently.
    - seanmcdirmid 4y ago
      Solar won’t work on new townhomes in Seattle with rooftop decks (since we don’t have to worry about snow so much?). There is simply no place to put them unless you give up your deck.
      - marssaxman 4y ago
        Alas, indeed. I'd have installed solar panels on the townhouse I bought in 2020 if there were anywhere to put them, but there would only be room for 800 watts, at most - not really worth it.
  - jamie_ca 4y ago
    Victoria BC area here (practically next door), it wouldn't work for us. My annual hydro bill was $2400 in 2018 with baseboard heating, and $2050 for 16,500kWh in 2021 after we put in a heat pump. 3 bedroom detached. A recent article suggested a typical 4 kW system around here would cost $10k for 3261 kWh a year, or about $405 in credit at a blended rate. Another suggests an 11 kW system at $27,500, which could maybe hit 9000 kWh - about $1100 in credit. We do have net metering with BC Hydro so it'll just wash through, but that's still a 25 year payback horizon.
    - efields 4y ago
      20 year payback horizon for us in MD, USA. And that's still would only covering 20-40% of our annual electric usage. We have a fully electric house. It doesn't take more than a couple trees in the wrong place to make you a lousy candidate for solar.
- 0x53 4y ago
  $25k / 12months / 9 years = $230. Which seems reasonable.
  - PaulDavisThe1st 4y ago
    a $230 monthly electricity bill in Seattle is a lot
    - TedDoesntTalk 4y ago
      ...which argues that it takes longer than 9 years to break-even. The panels lose a little bit of life each year, too.
    - danans 4y ago
      It depends on the house, the occupants, and lifestyle. 25k is the cost of a 9kWh PV array today, which will produce maybe 11GWh/year in Seattle. $230/month is about 1700kWh/month at Seattle electricity price of .13/kWh. That usage could easily be the amount of electricity used for an average efficiency 3000sqft house with 4 occupants and a couple EVs driving the median American commute. Add an electric hot tub, and $230/month isnt so crazy. Yes, it's very high, but not crazy high considering the typical upper middle class American home and lifestyle. In contrast, my home and lifestyle transplanted to Seattle would be 1/4 the usage and cost, but different preferences and all. In the example above the PV array would provide about 50% of usage, so about $115/month in bill reduction. The 25k is 18,500 after the Federal tax credit, which puts the payback at 13 years.
      - PaulDavisThe1st 4y ago
        Forgot about the EVs. Excellent point there. Always shocked by the labor component of PV arrays. I did my own 6.6kW array (split into two physical arrays, thus increasing the parts costs a bit), and it came out to around $13k. I don't mean I don't want to pay people a living wage, just always hard to remember (when you're used to doing stuff yourself) what fraction of the total cost that will be when you do pay them.
CyanBird 4y ago
Most of the planet is not "winter in northern latitudes" Indeed, most of the world is rather sunny and "not" located in "northern latitudes"
- throwaway5752 4y ago
  Most of the planet, most of the people are not in the Arctic. Brief search indicates 4 million, globally. You could have people in the Arctic powering their homes with peat or lignite and it wouldn't be a huge problem. Happily NG is better for this, and the rest of the world has fewer problems with solar seasonality.

Alaskan here; it doesn’t work so hot in the winter months. Even if they are kept clear by maintenance workers (not that hard or expensive to hire someone to clear snow from a panel) the sun’s azimuth is so low in the winter that there is hardly any energy produced.

fluoridation 4y ago
Small correction: you mean altitude, not azimuth. Altitude is how far you need to tilt your head vertically to look at an object. Azimuth is the compass direction.

edent 4y ago

Pretty good. You can download several years of data from my domestic panels at https://shkspr.mobi/blog/2020/07/1800-days-of-minute-by-minute-solar-generation-data/ https://shkspr.mobi/blog/2020/07/1800-days-of-minute-by-minu... Sure, some days they'll be covered by snow. But in industrial systems that can easily be melted / brushed off. Obviously they don't generate as much in winter as in summer. But cool bright winter days are surprisingly plentiful.

Analemma_ 4y ago

Very well. Rooftop solar in Seattle pays for itself in 7-9 years, and we have the least sunlight and cheapest grid power of almost any place in the continental US.

TedDoesntTalk 4y ago
> Rooftop solar in Seattle pays for itself in 7-9 years Can you show me the arithmetic for that? I understand rooftop solar to cost $20,000 - $25,000. Is your non-solar electric bill over 7-9 years really more expensive than that? Seems impossible.
- marssaxman 4y ago
  I'm afraid I don't have the exact numbers anymore, but I determined that the 2700W solar panel array installed on my Seattle house for about $14k in 2013 (including a new breaker panel) had paid for itself before the end of 2019. The system worked really well. People often think that solar won't work well in Seattle because it's cloudy so often, but light still comes in through the overcast, and solar panels don't care which angle the photons hit them from. Meanwhile, lower ambient temperatures mean the panels work more efficiently.
  - seanmcdirmid 4y ago
    Solar won’t work on new townhomes in Seattle with rooftop decks (since we don’t have to worry about snow so much?). There is simply no place to put them unless you give up your deck.
    - marssaxman 4y ago
      Alas, indeed. I'd have installed solar panels on the townhouse I bought in 2020 if there were anywhere to put them, but there would only be room for 800 watts, at most - not really worth it.
- jamie_ca 4y ago
  Victoria BC area here (practically next door), it wouldn't work for us. My annual hydro bill was $2400 in 2018 with baseboard heating, and $2050 for 16,500kWh in 2021 after we put in a heat pump. 3 bedroom detached. A recent article suggested a typical 4 kW system around here would cost $10k for 3261 kWh a year, or about $405 in credit at a blended rate. Another suggests an 11 kW system at $27,500, which could maybe hit 9000 kWh - about $1100 in credit. We do have net metering with BC Hydro so it'll just wash through, but that's still a 25 year payback horizon.
  - efields 4y ago
    20 year payback horizon for us in MD, USA. And that's still would only covering 20-40% of our annual electric usage. We have a fully electric house. It doesn't take more than a couple trees in the wrong place to make you a lousy candidate for solar.
0x53 4y ago
$25k / 12months / 9 years = $230. Which seems reasonable.
- PaulDavisThe1st 4y ago
  a $230 monthly electricity bill in Seattle is a lot
  - TedDoesntTalk 4y ago
    ...which argues that it takes longer than 9 years to break-even. The panels lose a little bit of life each year, too.
  - danans 4y ago
    It depends on the house, the occupants, and lifestyle. 25k is the cost of a 9kWh PV array today, which will produce maybe 11GWh/year in Seattle. $230/month is about 1700kWh/month at Seattle electricity price of .13/kWh. That usage could easily be the amount of electricity used for an average efficiency 3000sqft house with 4 occupants and a couple EVs driving the median American commute. Add an electric hot tub, and $230/month isnt so crazy. Yes, it's very high, but not crazy high considering the typical upper middle class American home and lifestyle. In contrast, my home and lifestyle transplanted to Seattle would be 1/4 the usage and cost, but different preferences and all. In the example above the PV array would provide about 50% of usage, so about $115/month in bill reduction. The 25k is 18,500 after the Federal tax credit, which puts the payback at 13 years.
    - PaulDavisThe1st 4y ago
      Forgot about the EVs. Excellent point there. Always shocked by the labor component of PV arrays. I did my own 6.6kW array (split into two physical arrays, thus increasing the parts costs a bit), and it came out to around $13k. I don't mean I don't want to pay people a living wage, just always hard to remember (when you're used to doing stuff yourself) what fraction of the total cost that will be when you do pay them.

CyanBird 4y ago

Most of the planet is not "winter in northern latitudes" Indeed, most of the world is rather sunny and "not" located in "northern latitudes"

throwaway5752 4y ago
Most of the planet, most of the people are not in the Arctic. Brief search indicates 4 million, globally. You could have people in the Arctic powering their homes with peat or lignite and it wouldn't be a huge problem. Happily NG is better for this, and the rest of the world has fewer problems with solar seasonality.