Comment by mabbo
20 hours ago
It really comes down to overcoming the Shockley-Queisser limit.
https://en.wikipedia.org/wiki/Shockley%E2%80%93Queisser_limi...
You can get around it with multi-layer, but each layer adds diminishing returns on improvements, while the cost keeps increasing.
The best way to handle places with less solar irradiance is to have more panels. The cost per panel keeps dropping, so the economics keep improving in that way.
Agreed adding more panels would work around the limitation. The reason I ask is that in theory there is room to reach upwards of 48%, the max being reached right now is around 32% and all the panels I can find that are mass produced are between 20% and 22% assuming one can even find the numbers, some companies are making the numbers hard to find. Anything above 22% appear to climb in cost exponentially.
With more panels my setup will be more of an eye-sore, require more and longer cables, combiner boxes and the setup becomes a bigger project. So I am just being a selfish ass but I had to ask where we are.
Multijunction solar cells (the ones that can get over 30% efficiency in theory or 25% in practice) are a completely different market. They generally go into satellites and research labs, not rooftops and power plants. That's why the numbers are hard to find.