Crazy little thing called supply and demand. And those two stories are from March. This is the new one:
Tesla drastically increases Supercharger prices around the world
Fred Lambert
Jan. 18th 2019 8:02 pm ET
https://electrek.co/2019/01/18/tesla-increases-supercharger-prices/
I like doing the math on those picture. In this case, my estimate of peak power is about 70kW for all of those solar panels (which I estimate at 330 panels). With conversion and maybe some other losses, maybe 60 kW available to the actual cars, again at peak (with the sun near dead-center, overhead), roughly enough to charge 1 car in an hour.
Since the sun don’t shine every day, and certainly don’t stay directly overhead all day, the equivalent number of peak hours over the course of a year (after factoring non-peak, nighttime, bad weather, etc.) typically comes out to 13% to 25% of what would be peak power if the sun were overhead 24/7 (the variation is mostly due to climate). Another way to look at it, is that the equivalent full charging hours comes out to 3 to 6 hours per day (in most of the US, and actually less than 2 hours in some places), again mostly climate dependent.
So, all those panels combined can charge 3 to 6 cars per day (assuming each car wants 60 kwh, which might be slightly high) - this is actually quite a bit higher than I expected. The rest of the cars that show up have to be charged off the dreaded ‘grid’. There are 24 charging stations in direct view (more in background), if each one were to see 12 cars per day, and if the station is in the desert (best for solar power), then 6 cars would get charged by the panels, and the other 282 would have to charge off of the dreaded ‘grid’.
http://www.solardirect.com/outdoor-lighting/solar/street/area-light/solar-insolation-map.html