Toyota developing solar-powered car for the road
Don't get too excited yet, but reports are coming out of Japan that say Toyota is developing a solar-powered car. First of all an electric car that draws electricity solely from the sun is still quite a few years off. The first stage is a car that gets some power directly from vehicle mounted solar cells with the bulk coming from being plugged into a solar array at home. This is really not much different than some Tesla Roadster owners like Martin Eberhard and Elon Musk are doing today, some with a SolarCity roof. Eventually, Toyota wants to create a car powered solely from on-vehicle photo-voltaic cells. That, however, is unlikely to come within the next decade due to the inefficiency of the energy conversion in those cells, not to mention the cost. Such a vehicle would also be highly impractical - if not outright unusable - in most areas due to insufficient sun exposure. Just having home mounted solar blended with grid power is likely to be the option for the foreseeable future. Thanks to Corey and Jarrett for the tips!UPDATE: Toyota denies the rumors.
Gallery: EVS23: Tesla Roadster and SolarCity
[Source: Associated Press]
Reader Comments (Page 1 of 1)
mmstowes 1:31PM (1/02/2009)
"Toyota wants to create a car powered solely from on-vehicle photo-voltaic cells. That, however, is unlikely to come within the next decade due to the inefficiency of the energy conversion in those cells, not to mention the cost."
Honest-to-God, if you know not what you speak, please don't spread the ignorance. Do your research first. Photovoltaic's have come quite a long way since the large bulky solar panels. Even so-called "industry experts" are way behind in their knowledge of PVs. The concept is far closer than you think...
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snp 1:46PM (1/02/2009)
You're a clown, do you know how much energy is produced by a 1x1 ft sheet of photovoltaic material? Do you know how much energy is in a beam of sunlight within a 1x1 ft surface area from the ground? Even if the photovoltaic material were to reach 100% absorption (impossible), there still wouldnt be enough energy. Even if costs were to drop down to the price of glass, it wouldnt be practical. Where would the sunroof go? If it snows will you be the one to climb on top of the car to let that bit of sunlight through? Are you going to only sell this vehicle below a certain latitudinal degree? The only way to get this to work is if you make the car much larger, but significantly lighter to get the energy output you need. At that point the vehicle would fail safety regulations cause you'd be rolling around in an empty trash can on the highway @40mph.
GoodCheer 1:55PM (1/02/2009)
mmstowes:
What are your numbers?
If you start from this (total solar energy in December) :
www.nrel.gov/gis/images/us_pv_december_may2004.jpg
most of the country is getting 3-5 kWh/m^2/day. You could have maybe 3m^2 on a car before it got silly, so 9-15 kWh/day.
Figure optimistically on 20% conversion efficiency (I know benchtop tests are higher than that, but 20% is still very good... right?) and you get 1.8-3 kWh/day, if you're in full sun all day.
Using 250 Wh/mile, that give you 7-12 miles range/day. I would call that inadequate.
What am I missing?
radler63 3:11PM (1/02/2009)
Now in SI units: Well, in urban operation you may well have 75 Wh per km, that gives you more range with solar (may be 2m²*0,5kW*4hrs*0,25=1kWh/75Wh=13km) - but the small vehicle should flip out more solar cells to be viable or position itself allways optimally in the sun. This introduces a new term "solar mover" fleeing shadow ;-)
why not the LS2LS7? 3:31PM (1/02/2009)
radler63:
A Wh is not an SI unit. All SI units that involve time use seconds (or 1/s). Joules are the SI unit you are looking for.
Chris M 3:40PM (1/02/2009)
GoodCheer. what you are missing is orientation. Solar cells only get their maximum power output when they are directly facing the sun, angling it away dramatically reduces power output. So, unless the car was equipped with a roof that pivoted and tracked the sun - potentially hazardous in high wind conditions - the cells would rarely be in an optimum position, and the total daily energy gathered would be even lower than you figured.
Oh, and of course there is the problem of shading by trees and tall buildings and other obstacles.
GoodCheer 5:00PM (1/02/2009)
Chris M.
You are quite correct, I was being generous. The NREL numbers I was using were for a stationary flat plate facing south, tilted to the local latitude. Most of America is between 30 and 45, meaning you then give away another 15 to 30 percent of the range I used.
I did include the conditional "if in full sun all day". That would (as you say) also be very hard to insure.
snp 9:17PM (1/02/2009)
@GoodCheer
You cant get 3m^2 on a car. That's the equivalent of 3yd^2. You cant imply that a battery sipping solar car can fit a 9ft x 9ft sheet of material on the roof of the car. I cant even lie on the roof of my car without half my body sticking out and I'm nowhere near 9ft tall or 9ft wide. 9ft x 9ft is the equivalent of a medium sized bathroom complete with tub, toilet, and sink. It'll never pass for going on the hood of the car for obvious reasons. Maybe the trunk, but that's only about 1x3 feet of usable space. Which now leaves you with less than half your calculated energy. Again, assuming no loss in the energy conversion from light to electricity, electricity to storage, battery storage to electricity again, electricity to motor power. We'll also assume there's no power windows, power steering, cd/speakers/radio, alarm system, wipers, and AC. Now further assume there's no further loss in energy from wind drag, road drag, and normal braking and WHAM!!! you've got yourself a nice 20-40k Tata Nano. You've invented the one piece of junk nobody would ever buy. If you consider brakes&drag, then you've gotta consider aerodynamics. So it would now be an ugly piece of junk no one would ever buy.
gorr 2:12PM (1/02/2009)
This is only the tips of the iceberg, the real news from toyota is hidden at 90% because they negociate their survival with big oil cartel and banks of wall streets and the republican party and the democrat party of wall street. They worked for them from the beginning 70 year ago. they always did what was told and they followed each and every orders killing millions of peoples over the years with toxic petrol and endless wars for tax-money-petrol.
Even if they followed the orders of u.s.a banks of wall street , they are still near bankrupcy without any power at all on anything and their friends let them down completelly because the banks of wall streets kill their friends by corruption and every corrupted people tend to kill themself after killing or ruining there previous friends. We can see it now because even the banks are bankrupts after having 100% of the power for a lot of years especially after 2001. AS of now nobody on earth have any power and money whatsoever. Only artificial credit is available to invest for a week maximum because after a week rules changes completelly. This is what happen when the players in the industry postpone the projects that i order.
What toyota said is that they can build a car that move forward with only a solar panel on top because nobody want to know that life is eternal and that there is unlimited power for all the devises with simple water-powered devises of all sort, including trucks, electrical generation, ships, etc. Toyota know because 2 year ago their president said that he can build a car that go from new york to los angeles while cleaning the air. Since then he eat his onw words to please the zombies and let go all the earth in the fuc&ing sink of endless dying. But strangelly with this limp news he still talk about their past coward decisions. Bring this f*cking car now on the market and maybe you will learn how to fu?k for the first time of your existance after the product that i ordered to buy over 2008 years ago will hit the market. He was there when i said that and it is his job now to do it , not me. Me im the buyer.
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jpm 2:39PM (1/02/2009)
Gorr, I'm not even sure what your wrote -- didn't read it, but you need to quit your long rants on Hydrogen b/c nobody cares.
snp 9:20PM (1/02/2009)
lol jpm. i didnt read it either, i skipped down to your remark and got my 5 seconds of laugh.
Jharlan 3:11PM (1/02/2009)
They have it right. This is the solution I have been seeing for some time. Out west here there is one thing we have the great majority of time and that is sunshine. PG&E just can't seem to figure out how to get a meter between us and the sun.Think about it, your electric car's batteries being charged while it sits in your solar garage. What a nightmare for OPEC. Right now it's a little pricey for most of us, but that is changing so quickly it's hard to keep up with it. This is technology available now. It's worth paying a premium for.
The thing that never made much sense to me was EVs that get their power from coal or nat gas powered utilities. Most people never gave it a thought, after all it does require some original thought. Where do electric cars get their power from? Solar makes good sense. I see decentralization of electric power production, especially in the sparsely populated areas of the west. For us who do not live in cities, freedom from a power utility is possible now, and soon will be economically imperative. The savings available are approaching the cost of capital investment.
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Richard in FLA 3:44PM (1/02/2009)
All we would need is enough for 30-40 miles a day. Of course, the panels could be replaceable in the event of progress to the conversion rate, but it would provide enough mileage for a days drive. Plug it in if you need more. I can see small vans with large roofs for more panels. Of course the side of the vehicle and the glass could serve as well. I can see this happening sooner than 10 years from now. I know there's a company in Sarasota that sells roof panels for golf carts. It's not that far fefcted. I cannot see, however, not using some sort of energy storage. Afterall, nighttime has no sun.
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gerrrg 7:55AM (1/05/2009)
I can see the solar cells offsetting the lowered gas mileage from using the air conditioner during the summer - when sunlight is greatest.
But it will only add onto the length of time required to BEP, on top of the already long BEP of a hybrid.
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miles 1:20PM (1/05/2009)
It may be able to offset the other sources of energy, but surely won't be the primary source but for a very small minority of people in very sunny climes that don't drive much.
One problem I haven't seen mentioned here is that the vehicle could not be designed to stay fully charged from the primary power source. If the car was fully charged, it would not be able to take full advantage of the free solar energy when available.
This means the hybrid or EV would need extra batteries to take advantage of solar, and that would bite into the benefit of having solar cells in the first place.
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