For all this remember that France has about a third of the insolation of California or Arizona per year, or maybe half at best in some places.
I don't think that is correct. This is a table of average insolation for different cities around the world derived from NASA's Surface meteorology and Solar Energy data set: http://stalix.com/isolation.pdf
Los Angeles gets 5.4 kWh/m^2/day. San Francisco gets 4.9. Lyon, Paris, and Toulouse get 3.7, 3.3, and 3.7 respectively.
I dunno if this is what gp meant to say but didn't convey properly, but the average per year is pretty irrelevant once you leave the subtropics. You need enough power for the lowest level of light part of the year, which is also the highest total energy use part of the year (much of that is achieved through individual home heating with burning fuel, but electrification is necessary to have any hope of even stalling climate trends).
I don't think that is correct. This is a table of average insolation for different cities around the world derived from NASA's Surface meteorology and Solar Energy data set: http://stalix.com/isolation.pdf
Los Angeles gets 5.4 kWh/m^2/day. San Francisco gets 4.9. Lyon, Paris, and Toulouse get 3.7, 3.3, and 3.7 respectively.