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He mentions that the mega chargers will all be solar powered. I don't know how this will be possible as the user base grows. The amount of energy needed for e

He mentions that the mega chargers will all be solar powered. I don't know how this will be possible as the user base grows. The amount of energy needed for even a small fleet will be huge.

petre 9y ago
So a charging station will need what, 10 hectares of land for the solar? Either that or 10 kW of grid interactive solar for marketing purposes, while absorbing the bulk of the electricity from the grid.
mkempe 9y ago
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.
- rand77763 9y ago
  There’s a lot of surface area on top of a trailer, just saying.
  - kmonsen 9y ago
    It will be stationary similar to supercharger
    - aerovistae 9y ago
      What? He meant you could put solar panels on top of a trailer.
  - Dylan16807 9y ago
    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.
    - larkeith 9y ago
      No, but you can improve the range by a few percent.
      - hermenaut 9y ago
        until you consider the weight of the solar panel
        larkeith 9y ago
        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 .
    - larkeith 9y ago
      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_.28HB-SIB.29 https://en.wikipedia.org/wiki/Solar_Impulse#Solar_Impulse_2_... [2] https://en.wikipedia.org/wiki/Helios_Prototype https://en.wikipedia.org/wiki/Helios_Prototype
      - Dylan16807 9y ago
        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.

He mentions that the mega chargers will all be solar powered. I don't know how this will be possible as the user base grows. The amount of energy needed for even a small fleet will be huge.

petre 9y ago

So a charging station will need what, 10 hectares of land for the solar? Either that or 10 kW of grid interactive solar for marketing purposes, while absorbing the bulk of the electricity from the grid.

mkempe 9y ago

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.

rand77763 9y ago
There’s a lot of surface area on top of a trailer, just saying.
- kmonsen 9y ago
  It will be stationary similar to supercharger
  - aerovistae 9y ago
    What? He meant you could put solar panels on top of a trailer.
- Dylan16807 9y ago
  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.
  - larkeith 9y ago
    No, but you can improve the range by a few percent.
    - hermenaut 9y ago
      until you consider the weight of the solar panel
      - larkeith 9y ago
        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 .
  - larkeith 9y ago
    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_.28HB-SIB.29 https://en.wikipedia.org/wiki/Solar_Impulse#Solar_Impulse_2_... [2] https://en.wikipedia.org/wiki/Helios_Prototype https://en.wikipedia.org/wiki/Helios_Prototype
    - Dylan16807 9y ago
      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.