Predictions

[Booga]

Assuming the footprint of a Tesla parking space is 15' x 10' and a panel angle of 15° due South, that gives us 155 ft² of panel space. Which could produce about 2.8 kW of power, a small fraction of the 120 kW of instantaneous power that the Supercharger requires. It could produce between 10 and 23 kWh of energy per day (depending on location), so about 15% of a charge per day.

So, yes, the solar panels will need to cover more than just the parking spaces taken up by the station itself. They will probably need to cover the entire parking lot that the Supercharger station is in, thus shading all the other cars and preventing them from heating up, and needing energy for AC.

Thank you kindly.

Thanks for doing that

Given that it's so little, I naturally wonder why Tesla would bother with the solar panels on some of these. They're better off buying land and putting solar panels out in bulk rather than a small amount on top of the roof of a supercharger if their goal is to supply power via solar.

 

[JeffK]

It depends on the location... some locations have 96 panels 200-300 peak watts a piece.

If you include all the time people are not charging across the globe at some of these stations the end goal is for Tesla to provide as much energy back to the grid as they use.

 

[Alketi]

Thanks for doing that

Given that it's so little, I naturally wonder why Tesla would bother with the solar panels on some of these. They're better off buying land and putting solar panels out in bulk rather than a small amount on top of the roof of a supercharger if their goal is to supply power via solar.

This post has some better examples of solar powered Superchargers. Solar power complemented Superchargers

As JeffK pointed out, these are packing 90-100 panels. At 250W / panel these would be generating ~35MW / year.

 

[aronth5]

Thanks for doing that

Given that it's so little, I naturally wonder why Tesla would bother with the solar panels on some of these. They're better off buying land and putting solar panels out in bulk rather than a small amount on top of the roof of a supercharger if their goal is to supply power via solar.

The heck with solar panels I just want a roof to keep the snow and rain away, but while they at it just add some solar panels

 

[Topher]

Given that it's so little, I naturally wonder why Tesla would bother with the solar panels on some of these. They're better off buying land and putting solar panels out in bulk rather than a small amount on top of the roof of a supercharger if their goal is to supply power via solar.

Because every bit counts, and is basically fungible. If you are going to put a roof over the chargers, it might as well be made of solar panels. I always assumed that Tesla would be putting in larger arrays, if their goal is to 100% offset the use of the energy use of superchargers. That said, unless the Supercharger is in a location with unreliable power, there isn't really any need to offset the energy locally, better to put the panels where there is a lot of sun.

This post has some better examples of solar powered Superchargers. Solar power complemented Superchargers

As JeffK pointed out, these are packing 90-100 panels. At 250W / panel these would be generating ~35MW / year.

Nice to see that Tesla understands how to arrange a roof full of solar panels, unlike Peugeot.

100 panels at 250 Watts is still only 25kW, so insufficient power for even one charger. And at most 200 kWh / day, so maybe 3 full charges in a day. Need WAY more panels.

Thank you kindly.

 

[JeffK]

Due to natural range anxiety I could see more people "topping off" rather than a full charge unless they are truly traveling long distance. Plus I think Tesla is relying on more of a net effect from all superchargers with solar panels across the grid and energy storage for days when few people charge if any.

Me, personally, I might use a supercharger about four or five times a year. There are probably many people like me who have a garage and have a typical daily commute. I rarely travel and mostly it's during holidays.

Inside a city, a supercharger would get a ton of use from apartment dwellers who don't have public charging options etc. but outside of a city I think it would balance out (with enough superchargers).

 

[Topher]

Due to natural range anxiety I could see more people "topping off" rather than a full charge unless they are truly traveling long distance.

I predict that this would be only an initial problem. Once people get used to an electric car, they will mostly just charge at their preferred place, every day. Just like charging a smart phone; you plug it in every night, whether it needs it or not. 'Range anxiety' becomes 'range obliviousness'.

Inside a city, a supercharger would get a ton of use from apartment dwellers who don't have public charging options etc.

This is where the math shows the problems. At the end of 2018 with 500,000 Teslas on the road, a city, say Boston, with 1 Million people will have at least 1,000 Teslas. Assuming three 'seatings' per night, the current single charger with 8 stalls will allow one to to charge once every 42 days. Even with double that number of SC, that still only give 10 miles per day for each car. And 30 of those miles are needed to get to and from the SC.

All the arguments about making Model ≡ owners pay or not are really moot in this scenario. There is just no way that the Supercharger network will ever be able to handle the daily needs of people who have no other place to charge. For 40 miles per day drivers, needing to charge at least once every 4 days, 24 charges per supercharger per day, that's at least one Supercharger for every 100 cars, 10 for Boston, 3,000 for the US just in cities. Plus as many more every year.

Thank you kindly.