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Any electric car can charge from solar...if you don't mind waiting 2 or 3 weeks.

Until the photovoltiac technology makes some epic technological leap, yeah, good luck with that.
 

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And who would buy a $150,000 car that you have to park outside all the time in order to charge it?
 

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As much as I like solar power, it isn't feasible to use it to power a car directly. Meaning your solar panels would have to be greater than 100% efficient to provide enough power for an average sedan at highway speeds. If they want to add a few watts of panels to it to reduce consumption or a deployable system while parked, great, however I think solar powered roads would be a more practical application.
 

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There are people who seriously want to make a car that can be powered by the sun.
It was founded by alumni of TU/e, which won the World Solar Challenge Cruiser Class in 2015.

Like those companies trying to build solar airplanes, I'm glad they're trying and I'll be interested to see how far they can push it.

Also note that the car would still be powered by the sun if you charged it at home using solar panels. ;)
 

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Also note that the car would still be powered by the sun if you charged it at home using solar panels. ;)
That's different though, one is usually talking a far larger array than what you could install on a car. The limitation in the latter is square feet - the amount of solar panels you can stuff onto a car is token in comparison to the requirements to actually charge it in anything less than many, many days...assuming full sun.
 

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Not hard to do the math on how much area you need. If we assume 8 hr per day of sun (might be a bit high) and we need to charge a volt. So 15 kWh from 8 hr is about 2 kW per hour, with 1 kW per sq meter from the sun with 20% effiency, you would need 10 sq meters of panels.
 

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The sun provides roughly 1000 watts per square meter with sun perpendicular. A car might take at minimum 10 kw to drive at a reasonable speed on the highway, but the engine in the Volt 1 is like 60 kw to cover most situations (not mountains at highway speed). If you wanted say 20 kw of power and a small battery to get surge amounts, you would be looking at 20 m square surface area at 100 % efficient at the equator at noon. So at 25% efficient that goes to 80 m squared. This is about 2.5 40ft semi trailers worth of solar panels, and that weight now requires a lot more than 20 kw...

Solar will never ever work to power a traditional class vehicle at highway speeds, it is physically impossible. However, it could work for a non traditional vehicle, but I think it is a waste of time. Solar power to charge a battery is better, or a solar road that has massive area to wirelessly charge cars in transit is feasible. Again, a deployable panel to charge your car in the desert would be cool, roof mounted not so useful (maybe on semi trucks to extend range or provide refrigeration power).
 

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Agreed, powering a car fully by the sun cannot work. However, as a supplementary power source is could make a lot of sense. A typical car has 1 to 2 m^2 of usable top surface area. That should provide at 1 to 4 kWhr on a sunny day. For comparison, my 2014 Volt has a max capacity of about 13.5 kWhrs, so the energy from the sun is more than negligible. Especially, when you consider that all the electronics in any modern car are constantly drawing power even when the car is parked. This is can be even worse on fully electric cars. I would feel a lot more confident about leaving such a car in the airport parking lot for long trip. So, if solar panels become cheap enough, why not slap them on a car?
 

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Good thing visionaries in our society don't listen to this crowd. If they did none of us would be driving something called a Volt.
 

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Agreed, powering a car fully by the sun cannot work. However, as a supplementary power source is could make a lot of sense. A typical car has 1 to 2 m^2 of usable top surface area. That should provide at 1 to 4 kWhr on a sunny day. For comparison, my 2014 Volt has a max capacity of about 13.5 kWhrs, so the energy from the sun is more than negligible. Especially, when you consider that all the electronics in any modern car are constantly drawing power even when the car is parked. This is can be even worse on fully electric cars. I would feel a lot more confident about leaving such a car in the airport parking lot for long trip. So, if solar panels become cheap enough, why not slap them on a car?
It's more cost effective to build a solar roof over the EV parking stalls -- saves worrying about aerodynamics, the panels can be elevated to the correct orientation for the latitude, and there's about 20 sq meters per stall instead. That's enough power at typical efficiencies to pump an 8-amp Level 1 charge to the car below through the midday.
 

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It will be interesting to see what Toyotas experience will be with the solar roof on their Prime (Japan and Euro cars only.) It is a 180 watt panel with an additional NiMH battery and DC-DC converter to buffer power between the panel and the traction battery. If ones gets a 'free' mile or two a day, that is kind of fun in a geeky way - even though it makes zero financial sense.

The 120 watt roof on the Fiskar Karma looks awesome. But from what I have read, it only does 12v trickle charging and vent fan duties.
 

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I wonder if solar cells would be an effective means of cooling a parked car in a hot climate. Solar energy that's turned into electricity isn't turned into heat and the electricity can be used to power the air conditioner of a parked car. On the other hand solar panels are designed to absorb solar energy and they are only about 20% efficient so the remaining 80% is turned into heat. White paint reflects the sun's rays rather than absorbing them which makes white the best choice for cars in places like Texas. So the question is, if your car is sitting in a parking lot in Texas with no shade available would using a solar roof coupled to the AC leave your car cooler than simply buying a white car?
 

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Good thing visionaries in our society don't listen to this crowd. If they did none of us would be driving something called a Volt.
A fair argument, but we are talking some pretty well known limitations of solar power. Until the technology make some quantum leap there's no visionary out there that can make a solar car realistic.

To suggest that a visionary could somehow solve this is akin to suggesting that we should have had 250 mile electric cars in the 50's because there were visionaries then. The reality is however, that the battery technology just wasn't there at that time.
 

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To suggest that a visionary could somehow solve this is akin to suggesting that we should have had 250 mile electric cars in the 50's because there were visionaries then. The reality is however, that the battery technology just wasn't there at that time.
Which is said in this video.
 

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A fair argument, but we are talking some pretty well known limitations of solar power. Until the technology make some quantum leap there's no visionary out there that can make a solar car realistic.
'zactly. The amount of insolation is a measurable known that won't change until we blow off the atmosphere. The conversion rate of that to electricity by photovoltaic cells is known, and changes slowly. (We're not going to get 100% efficient cells tomorrow. We MIGHT get flexible cells from ~20% efficient to ~25% sometime, over a relatively short couple of years. It's happened before. Fixed panels are up to about 45% for the best of the best, and "cheap crap" ones are 25-30%.)
 
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