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Their claims are somewhat surprising, and I guess they reflect advances in solar cells. My 2014 Prius has a rooftop solar panel, smaller than depicted, and uses

Their claims are somewhat surprising, and I guess they reflect advances in solar cells. My 2014 Prius has a rooftop solar panel, smaller than depicted, and uses it solely to power a fan while the car is off. Then again, the battery pack in the Prius (not Prime) is so small, perhaps it wasn't worth trying to connect the two.

neo4sure 7y ago
https://qz.com/1482588/why-teslas-dont-and-cant-have-solar-roofs/ https://qz.com/1482588/why-teslas-dont-and-cant-have-solar-r...
- neo4sure 7y ago
  https://www.quora.com/Why-doesnt-Tesla-make-cars-with-a-sun-roof-with-solar-panels https://www.quora.com/Why-doesnt-Tesla-make-cars-with-a-sun-...
agumonkey 7y ago
I still wonder how better suited to vans the idea is.
- bryanbuckley 7y ago
  I thought Tesla or Mercedes would have one by now. Diesel generator optional.
  - rtkwe 7y ago
    They don't because the energy available isn't enough to appreciably add to the range of the vehicle.
    - bryanbuckley 7y ago
      To be fair, I am mostly surprised there are not yet EV or hybrid vans, versus PVs on the roof. Seems like stop-and-go, or lots of idling, fleets would benefit signifigantly. I imagine vans use the battery for more than propulsion, so PVs on the roof might be welcome. Charging from a generator is probably still more cost-effective, except for some niches (e.g. boon-docking). Lots of van-dwellers have PVs on their roof.
- Yeroc 7y ago
  Pretty much just as unsuited. Even if a van has 3 times the area available to solar panels it's still a negligible amount of energy... By the way, the best book and/or course I've read for building intuition for these kinds of questions is "Physics for Future Presidents" by Richard Muller. He used to teach it as a course at CMU and I believe the lecture series is still available to watch or listen to online. Very worthwhile.
  - agumonkey 7y ago
    I know the amount of energy is small. But IF a company spends time on solar over a normal car, doing so on a van seems 3x better. Even if it doesn't power the motor, a van can have appliances, tools that can be powered by a .9kW setup (I think that could fit on an average van roof) Also, they have more flat surface for batteries at the bottom too.
jerf 7y ago
"With six hours of charge per day, the vehicle could increase travel distances by 1,300 kilometers per year." (or 800 miles per year) One of the things I do to keep myself accountable for all the subscriptions in modern life is to annualize them, so it's not "just $10/month!" but "$120". But in this case, I think we want to flip it around; at 6 hours of charging you're going to get... approximately two miles per day. Three if you're inclined to round up through the pile of lossy conversions I'm pushing that number through. And that's only going to be in play when the battery is not already full, and it probably won't work while you're charging, either, because the charger will be saturating the battery's incoming charge rate. I don't find anything particularly unbelievable about that, but it's a marketing stunt, not a good engineering idea, as evidenced by trying to present this in terms of "km per year". That's worthless, swamped in the noise of how your driving style will affect your mileage on an electric car (or any car).
- dmix 7y ago
  The idea of your vehicle sitting there and gathering "clean" energy has a feel-good thing to it, so it's definitely useful as a marketing gimmick to the green people.
  - jerf 7y ago
    More productively, if you are worried about this sort of thing, you can recover this amount of energy most likely today if you Google the term "hypermiling", read up, think, and then don't do anything stupid but tweak your driving style with what you read. Bonus, you can do this with any type of car, including whatever it is you are driving now. This will cut your energy usage by wildly more than anything this solar panel can do. However, please let me re-iterate, don't do anything stupid. That term will lead you to some stupid things to save trivial amounts of energy.
    - dmix 7y ago
      As long as it doesn't involve going 5km/hr down an offramp hill because you don't have to use gas but there's a massive gap in front of you and a hundred cars behind you forced to go your speed (which is far more challenging at low speeds, especially with a standard vehicle like mine). It's a really selfish and inefficent move IMO and I see it all the time in the city from a small group of people. If you want to save gas go into neutral and go as fast as everyone else or don't do it unless you're alone.
r-s 7y ago
I learned recently that some older cars also had this feature. A 1992 mazda 929 had a solar sunroof option to power some fans. Quite a few early 2000s Audis had this as an option as well.

neo4sure 7y ago

https://qz.com/1482588/why-teslas-dont-and-cant-have-solar-roofs/ https://qz.com/1482588/why-teslas-dont-and-cant-have-solar-r...

neo4sure 7y ago
https://www.quora.com/Why-doesnt-Tesla-make-cars-with-a-sun-roof-with-solar-panels https://www.quora.com/Why-doesnt-Tesla-make-cars-with-a-sun-...

agumonkey 7y ago

I still wonder how better suited to vans the idea is.

bryanbuckley 7y ago
I thought Tesla or Mercedes would have one by now. Diesel generator optional.
- rtkwe 7y ago
  They don't because the energy available isn't enough to appreciably add to the range of the vehicle.
  - bryanbuckley 7y ago
    To be fair, I am mostly surprised there are not yet EV or hybrid vans, versus PVs on the roof. Seems like stop-and-go, or lots of idling, fleets would benefit signifigantly. I imagine vans use the battery for more than propulsion, so PVs on the roof might be welcome. Charging from a generator is probably still more cost-effective, except for some niches (e.g. boon-docking). Lots of van-dwellers have PVs on their roof.
Yeroc 7y ago
Pretty much just as unsuited. Even if a van has 3 times the area available to solar panels it's still a negligible amount of energy... By the way, the best book and/or course I've read for building intuition for these kinds of questions is "Physics for Future Presidents" by Richard Muller. He used to teach it as a course at CMU and I believe the lecture series is still available to watch or listen to online. Very worthwhile.
- agumonkey 7y ago
  I know the amount of energy is small. But IF a company spends time on solar over a normal car, doing so on a van seems 3x better. Even if it doesn't power the motor, a van can have appliances, tools that can be powered by a .9kW setup (I think that could fit on an average van roof) Also, they have more flat surface for batteries at the bottom too.

jerf 7y ago

"With six hours of charge per day, the vehicle could increase travel distances by 1,300 kilometers per year." (or 800 miles per year) One of the things I do to keep myself accountable for all the subscriptions in modern life is to annualize them, so it's not "just $10/month!" but "$120". But in this case, I think we want to flip it around; at 6 hours of charging you're going to get... approximately two miles per day. Three if you're inclined to round up through the pile of lossy conversions I'm pushing that number through. And that's only going to be in play when the battery is not already full, and it probably won't work while you're charging, either, because the charger will be saturating the battery's incoming charge rate. I don't find anything particularly unbelievable about that, but it's a marketing stunt, not a good engineering idea, as evidenced by trying to present this in terms of "km per year". That's worthless, swamped in the noise of how your driving style will affect your mileage on an electric car (or any car).

dmix 7y ago
The idea of your vehicle sitting there and gathering "clean" energy has a feel-good thing to it, so it's definitely useful as a marketing gimmick to the green people.
- jerf 7y ago
  More productively, if you are worried about this sort of thing, you can recover this amount of energy most likely today if you Google the term "hypermiling", read up, think, and then don't do anything stupid but tweak your driving style with what you read. Bonus, you can do this with any type of car, including whatever it is you are driving now. This will cut your energy usage by wildly more than anything this solar panel can do. However, please let me re-iterate, don't do anything stupid. That term will lead you to some stupid things to save trivial amounts of energy.
  - dmix 7y ago
    As long as it doesn't involve going 5km/hr down an offramp hill because you don't have to use gas but there's a massive gap in front of you and a hundred cars behind you forced to go your speed (which is far more challenging at low speeds, especially with a standard vehicle like mine). It's a really selfish and inefficent move IMO and I see it all the time in the city from a small group of people. If you want to save gas go into neutral and go as fast as everyone else or don't do it unless you're alone.

r-s 7y ago

I learned recently that some older cars also had this feature. A 1992 mazda 929 had a solar sunroof option to power some fans. Quite a few early 2000s Audis had this as an option as well.