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Comment by mkempe | Hacker News Reader

In the year to 2017-Aug, total US solar generation was 72.1 TWh, amounting to 1.80% of total US electricity (predicted to reach 5% by 2022; in 2016 US solar capacity almost doubled from the year before).

Tesla semi consumption: < 2 kWh/mi

One charge: 500 miles => < 1 MWh

There are about 2 million semi trucks in the US (tractor trailers). Assume that each semi fully charges once a day, 300 days a year.

The conversion of all of the country's semis to Tesla vehicles powered with solar generation requires under 600 TWh a year, eight times current US solar level; still only 15% of current total US electricity generation. Likely within 10 years, or sooner.

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There’s a lot of surface area on top of a trailer, just saying.

It will be stationary similar to supercharger

What? He meant you could put solar panels on top of a trailer.

30 square meters, laying flat. So maybe 3kW. While the engines need more like 100kW.

You can't effectively power any vehicle with 15% efficient solar panels.

No, but you can improve the range by a few percent.

until you consider the weight of the solar panel

Going with a weight of 20 lbs/m^2, that's only 600 lbs - less than 1% of the fully-loaded weight.

It's fairly likely one could get well below that mass using some of the more experimental solar panel designs (such as those in use for solar aircraft), but it would probably not be cost-efficient .

One note, your second claim is not entirely true - while land vehicles are a ways from being feasible to power with photovoltaics (although I would have to do the math for trains, which may be close), we already have primarily [1] and exclusively [2] solar-powered aircraft.

[1] https://en.wikipedia.org/wiki/Solar_Impulse#Solar_Impulse_2_...

[2] https://en.wikipedia.org/wiki/Helios_Prototype

Those aircraft limp along at a tenth the speed of a typical commercial flight. That's the main reason I said "effectively". I mean, there are useless pure-solar cars too.

Trains might be closer but when single locomotives are measured in megawatts I'm not very confident.

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