Yet more rumors of a solar Prius

A solar-paneled Prius done by Solar Electric Vehicles.

(Credit: SEV)

Toyota is developing a solar-powered Prius, the Nikkei newspaper has reported yet again.

It was interesting when we heard about this in July.

But it seems to us that someone over at Toyota has now been fake-leaking/hinting news about a solar-powered Prius in one form or another for at least the last year.

This wonder-car-in-the-making has gone from being a Toyota Prius that uses solar roof panels from Kyocera to power its air conditioning unit, to "a vehicle that will be powered solely by solar energy" to quote one recent Associated Press article.

You may find it interesting that this rumor always comes floating by on the heels of bad news from Toyota.

In July, it accompanied news of a series of Toyota plant closings/reorganizations in the U.S.

This latest rumor seems to be timed to follow Toyota's December news that it, too, has succumbed to the world auto industry slump, reporting its first annual operating loss in 70 years, and a series of consolidations and changes in its organizational structure.

Of course, there is already an available solar option for some Toyota owners in the U.S.

Solar Electrical Vehicles (SEV) has been offering an after-market Prius solar overhaul since June 2007. It includes a customized solar panel for a Prius roof that can improve the car's efficiency by about 29 percent. SEV also offers kits for the Toyota Highlander, Rav4 EV, and Ford Escape Hybrid.

For those who just like reading about the idea of a solar car, Canadian engineer Marcelo da Luz and his team have been blogging about their attempt to set the world long-distance record for a solar-powered car with the Power of One (Xof1) vehicle.

[johnnydfred]

Rumors is right. Toyota would have to completely revolutionize solar cell tech to get even a fraction of the power required to run an automobile. Heck, a roof full of current cells isn't even enough to power today's auto air conditioners. Until they rewrite physics laws, or hook up a trailer with a field full of solar arrays, this report goes nowhere.

[BigGuns149]

I agree. Ultimately the vast majority of the power is going to come from a battery, so why not nix the solar cells and just make a more affordable/practical electric car. If somebody could make an affordable car that used capacitors the charge time would be measured in minutes instead of hours. You eliminate the hurdle of long charge times and electric cars would be practical for people who require longer ranges. Either that or make an electric car that is considerable less expensive to recognize the greater limits upon the use of the vehicle.

Solar cars are little more than a novelty because most of their energy won't come from the sun.

[Renegade Knight]

The thing is you don't have to run the entire car on solar to make the car more efficient by using solar. Your thinking too big. Think smaller. Even if all you did was top off the batteries while the car sat it would gain efficiency. Of course there are more options that don't require a trailer of solar arrays.

[Penguinisto]

Well, here's the trick - maybe it isn't to power the whole thing on-the-fly.

Consider that for most of the time, your car just sits somewhere - in the driveway, in the parking lot at work, in the parking lot of some mall/grocer/whatever... So as long as you don't park it under a roof of some sort, it makes a lot of sense to have solar panels recharging your hybrid's battery instead of having the gasoline engine do it all of the time.

a 25% (avg, assumed) jump in fuel efficiency would , on an (again, avg) 38mpg Prius, push things to ~47mpg... which could add up big-time over the life of the vehicle. Those who live in, say, Arizona would probably see even bigger returns.

[BigGuns149]

It is a neat idea, but somehow I think that the 25% jump is a bit overly optimistic. Unless the energy savings made the total cost of ownership of the vehicle cheaper within a few years I doubt this would be more than a novelty amongst the uber green crowd.

[Penguinisto]

I actually dialed the claimed efficiency boost number back to 25% from the claimed 29%, and dropped the Prius' mpg number down from its claimed ~43-45 mpg.

[sanenazok]

Me thinks 2.5% increase is more likely...with a 10% hike in initial cost.

[Penguinisto]

Dunno - the size of that panel looks like it could deliver enough wattage to make it worthwhile. About the size of a residential rooftop panel, which would put out roughly enough to charge a car battery in a few hours, and about 25% of a hybrid battery array's charge in about five-six hours.

Naturally ('scuse the pun) YMMV.

[Jack K1]

So, how much does this SEV thingy cost - and why exactly do we need a bigger battery? What's the overall return? And what's the environmental impact of producing these solar cells? Is this green technology - or another b.s. "green" fashion statement? Or does technology hold no real interest for you?

[Penguinisto]

Typical solar cells are usually built from silicon.

ref: http://en.wikipedia.org/wiki/Polysilicon#Monocrystalline

if you want to know the basics instead, start here: http://en.wikipedia.org/wiki/Photovoltaic_module

The environmental impact is actually more efficient and less impactful than by growing biofuel (considering the costs associated with growing, transporting, then processing plants into fuel).

[Manhattan2]

Tell me this isn't true. Putting solar cells on a car? There is only one way to build a solar car. We call it a solar transfer car and when it is released Toyota, GM and Ford will have to revamp their concept of using solar power to propel a vehicle.

[Penguinisto]

Ah yes - more spam. At least you didn't plop down the URL... again.

[fokkwp]

Start from atop Mt. Evans in Colorado - 14,000 paved feet up - and coast on down. Those solar panels will "power" the descent and maybe even keep the radio going.

[sanenazok]

Yes, the radio and even a few blikers, but not the hazard lights, only turning signals.

[RobertFHarwood]

I know that Zap has had an option for their Xebra electric sedan and pickup for awhile. When they introduced their concept car that was designed with Lotus Engineering, more then a year ago, which was reported in News.com, they talked of a solar power element. The solar power was said to trickle charge the batteries for a five percent of the power need.

[Manhattan2]

Make sure things make sense before you go green. Sometime you are just being sold on the color not the intent. Mitch Govansky for Solar Transfer

[William Crow]

Solar cells are just another way to feed the batteries. I think its a great idea - a trickle charging system.
Pricewise, the sooner solar cells become commodities the better. They'll be everywhere. Imagine solar roof shingles.
I might spend the extra money, if reasonable, for a system like this if it keeps my money from going to overseas oil states.

[Renegade Knight]

You at least understand the concept. It's all about frog hairs. All the little things you can do to up efficienty. High Pressure Tires. Synthetic Oil. Free flowing exaust. Fuel Injection. Drive lightly. Lighter Materials. Hybrid Technology. Next thing you know you have a car that can do an honest 50mpg around town. Solar is the next frog hair. A step towards the plug in hybrid concept without needint to plug in. 5%? better? Thatsan extra 2.5mpg around town.

[AppleSuxLeo]

The flatulence engine would stand a better chance of working than a car with the current state of solar panel efficiency. The whole roof covered with current-tech solar panels would be hard pressed to charge a cell phone ;)

[benjwah]

You're a twit. The flatulence engine is years away from completion.

[NiraliSherni]

A solar powered Prius sounds like a marvelous idea. However as of now solar batteries are not so advanced that they would power a car on their own. It would be useful to have the solar panels assist a PHEV or an pure electric such as the solar panels available for fitting on the Xebra car and truck produced by ZAP, which helps increase the range of the EV.

[Penguinisto]

That's the thing - they're not made to actually power the car (the amperage delivered would be way, way, WAY too low for that). They're sold to help you charge the batteries.

Right now, you can get mass-produced solar panels that get 18% conversion, and one of the size shown in the article could conceivably (not sure because I don't know who makes the cells) be sufficient to fully charge your batteries in about 3-4 hours of sunlight. That's a trip to the Mall...

[ralfthedog]

It could be coo (bad pun)l. Solar power could not run an AC unit, however it could run a fan. Blowing all the hot air out of your car in July could be nice. The solar panels could also provide a bit of an assist for those of us who work 12 hour days. Show up to work at 7 A.M. Let your car suncharge until about 7 P.M. It would not be enough to charge your battery all the way up, but it might give a bit of a help.

A better option would be for companies to provide charging stations for people who drive plug in hybrid electrics. Get a green car, get a preferred parking space and the company pays the charge for your drive home.

[Jack1776]

>Solar power could not run an AC unit, however it could run a fan. Blowing all the hot air >out of your car in July could be nice.

I have heard that, at highway speeds, AC is more efficient than the drag induced from open car windows.

>A better option would be for companies to provide charging stations for people...

I agree, possibly the gov could kick in something as it will be in the public interest.

[GALLERY84]

i was hoping gas would stay at 4.00 a gallon just so we can get these battery and solar cars on the road now back below 2.00 all the r and d stops and we start over

i realy think this sort of thing is planned by big oil .just when we get close the price drops , good luck keep up the hard solar and battery work its the future clearly when solar or battery takes over the price of gas will go down to 50 cents

[sanenazok]

Just awful! Yeah everyone else is a conspirator, but not you, even though you *want* gas prices to stay high to push your randomly chosen favorite tech. Niiiiceee.

[forever4now]

This could be a positive step, toward the entire car shell being embedded with solar cells (ideally in an inconspicuous way). As solar cell technology and efficiency improves, more and more energy will be available to do more things.

[conorneu]

The Fisker Karma is doing the same thing by adding solar panels to their roof. I believe it is an optional feature that is primarily used for keeping the car cool (running low A/C) while the car is parked.

I think it is fairly clear that the solar panels will not be entirely powering the car, but what is the downside in taking advantage of every extra source of power possible? It is also helpful for technological advancement to keep trying these new technologies in new ways. This is similar to the regenerative-braking power these cars are also starting to use. What is the downside?