Hello everyone and happy holidays!
I’m interested in photovoltaic panels, it’s the future and all!
But with the subsidiaries and the general enshittification of search engines, all search results about photovoltaics leads to sites with wildly misleading information, IMO.
I don’t care about a 3kWc system with installation. What even is a kWc (I know what it is) and why is nobody explaining how much power the panels would typically yield instead? Per month? During the day?
I guess it is less selling if your installation is generating near nothing in December when you need it the most?
Okay sorry, rant off. My question is, where can I find reliable information about how much panels generate every month, during the day?
I know places have more or less sun, but that’s quite easy to figure out if you have the numbers for any place.
🌞
Edit: I don’t need a web calculator for how many panels I need. I’d like to know roughly how many watt a typical panel produces a specific day (or better hour) in the year.
Edit2: I am not looking for how to install or calculate a typical solar panel setup. I’m looking for the typical real world output of solar panels around the day and year.
Edit3: got my information, thanks oo1@lemmings.world ! You all can now continue explaining how many panels a home needs or what a kwh is, Merry Christmas to you all!
It’s very circumstantial, slope and orientation make a big difference. so it has to be a calculator where you put in specific information.
I think this does it: https://pvgis.com/
There’d nbe loads of others. I’d expect most reputable solar installers aimed at residential to have calculators, or recommend one as part of the planning process. Maybe with localised assumptions. There’s one from a govt funded body in my country that makes cost and price assumptions too tand gives a ‘return on investment’ guess.
Wow that’s kind of technical :-) but monthly irradiation is accessible!
Edit: according to those figures a 1m²@20% panel would yield 55w averaged out on 24h, in the summer, and 14w/m² in December.
That’s numbers I can work with, thanks!
The solar atlas is another good starting point for making these calculations. Just by looking at the map, you can easily see how location makes a big difference. Solar power in Spain will be pretty good, while in Germany it’s a bit meh. If you’re in Scotland or Norway, solar power will be even worse. Well, you can always compensate by buying more panels, but that’s not great either.
The actual output is also greatly influenced by quite a few variables, like angle, and efficiency of the panel. As the panel ages, the efficiency goes down. Also, higher temperatures decrease the efficiency of the panel, so the burning hot panels in Libya might not produce as much as you thought based on the solar irradiance map. In other words, it’s complicated.
Check out this: https://globalsolaratlas.info/map
Be sure to check out the details, it has the exact specs for your location.
That’s a neat tool. But it’s giving me a slightly confusing result. I have a solar installation and I’ve plugged in the details so far as I know them, just to see if I’m producing about what I “should” be. The peak production month is about right, but the minimal production month is only estimated to be like 25% less than that. My system has more like 50-60% drop, and some quick googling suggests that’s about normal.
Any thoughts on why this tool suggests a much smaller drop?
No idea. The ‘typical meterological year’ is likely smooth some extremes - that will likely have less variance than any actual year. Maybe the geographical resolution is poor leading to more averaging. But that sounds a bit large of a difference to be just that. Was the total annual production way out?
Check some other tools , maybe a local one - another one might have better data on some things. Some consensus of several estimates might be better than relying on one calculator only.