A simpler explanation would be that he's not telling the whole story, and that perhaps they have dedicated solar farms in development/deployment or something to that effect. Don't afraid to dream a little bigger, darling.

You bet your ass he quadruple checked those numbers.

I'm guessing that the supply at these stations will be much higher than the demand for charging, so they'll make up the cost of "free" by selling wh's back to the grid.

Again, this is a guess based on a CG rendering on their website. That drawing doesn't constrain Tesla's engineering talent in any way – even without using extra land they could put up solar shade structures over adjacent parking spaces.

Assume you've got a couple dozen slots, charging 100 cars a day. (Far, far fewer than an equivalently-sized gas station. If we're going to transition to an electric-only transportation infrastructure, then car changing stations are going to become a common sight)

That's 9 megawatt-hours a day. A random solar panel calculator I found guesses that would need ~2000KW of solar panel capacity. So you'll need 8,000 250 watt panels. That'll cover 9,600 square metres, (2.6 acres-- if you're lying them flat, which you won't. A big dedicated solar generation station will use tilted one-axis tracking, which will use a lot more ground space) and cost you (at $410 a panel) a cool $2.4 million.

(Google's big solar installation at Mountain View, the one that got so much press, was only 1700KW. Our tiny electric car charging station has to be 17% bigger than it.)

Electric car charging uses a lot of power. Solar is great, I love solar, but it's not space-efficient, or cheap. Either Tesla is going to build a national solar generation network on the scale of Germany's move into solar power, all on their own dime, or they're lying through their teeth about charging draw/solar production breakeven.

I don't think Elon Musk would green-light the "100% solar power" line without doing the math. Again: you can argue about whether he's lying, but I can guarantee you he knew exactly the scale of what he was promising. That makes it all the more impressive, imo.

Re:lying, I'm imagining at some point they'll transition over to "we buy 100% solar power for SuperChargers", which is fine by me since it's functionally equivalent to what they're doing now.

Perhaps solar in previously undeveloped areas would be better? I doubt that. Developing solar plants in undeveloped areas only to put the charging stations in urban areas (that is where the market demands them after all) hardly seems better than putting charging stations in urban areas and sticking some solar there too. What is there to be gained from not putting solar wherever you can?

That said, I think we should be plastering the land we already use with solar panels. Might as well put all those rooftops to use.

I also think there is likely a lot to see in the future of non-panel-type solar. That generally involves a much larger or smaller scope than panels though, "medium" sized doesn't work well.

Have you ever looked at satellite views of the US? There are massive deserts just begging for the shade of some solar panels or mirrors. No use in heating up all that sand.

It's not so hard to move the energy out of the desert either. Just run wires, or better, relocate an aluminum smelter from the grid to out near the solar array.

It's tougher than you realise. Energy is lost when transmitting power over long distances - like from a desert to an urban area. I'm not an expert but as I understand it there are major challenges. A lot of solar installations tend to be located where the power is used (next to data centres, on people's roofs).

Considering all the infrastructure that goes into keeping a fossil or nuke plant fed and cleaned and its power output distributed, I think if a solar installation has a net payback time of similar period we ought to be willing to invest a little in the distribution as well.

Why aluminium smelters? I haven't heard this before.

> we ought to be willing to invest a little in the distribution as well.

I agree. I've read that's it's a huge challenge though, which is one of the factors holding up the development of large scale solar installations in the desert. Another challenge is the variance and relative unpredictability of power generation which means batteries are needed to smooth out the peaks and troughs to balance supply and demand.

> Have you ever looked at satellite views of the US?

My thoughts exactly. I think looking at Europe could bring a new perspective into what does 'lacking space' mean.