How-Solar cars on public roads ?

[Cd]

Hey guys I have a question for you all :

I notice that although solar cars are almost always followed by chase vehicles, they still seem to lack turn signals and rear view mirrors that the rest of us use for safety. Add to this the fact that the cars are so tiny that they appear almost invisible to other drivers.

What all is involved in getting these cars legal for road travel ?



On a related note, I would love to ride a 'velomobile' HPV to work, but the idea seems impossible. Do any of you folks actually ride your 'bikes' on public roads ? If so, how do you signal when you want to brake or turn ?

Thanks

[Ryland]

if it's 3 wheeled it can be titled as a motorcycle or moped, it still needs a single mirror, full set of lights for motor cycles but turn signals are optional for mopeds although with mopeds you need to use hand signals if you don't have light turn signals.
with the solar race cars they often have special permission to operate them on the road and part of that is having a chase vehicle.

[jesse.rizzo]

I think the issue is that with current photovoltaic technology, you couldn't power a car solely on those, and have it look anything like a car. There was a recent post here about a guy who drove across the U.S. with a completely solar powered car. He had to pull a trailor full of batteries and topped with PV panels. I think short of that, you just can't get enough power to drive anything other than a super aero, non street legal vehicle like the one pictured in the OP.

It will probably just be a matter of time before PV tech evolves enough to power a car shaped car.

[jamesqf]

Originally Posted by jesse.rizzo

It will probably just be a matter of time before PV tech evolves enough to power a car shaped car.

Not even possible. You're up against basic limitations of nature, starting from the fact that sunlight has only about 1000 watts per square meter - and that's in orbit. Atmospheric attenuation is going to reduce that - maybe not too much in the middle of Australia, but a whole lot in Seattle or the Northeastern US.

Then consider that the effectiveness of solar cells is reduced by the cosine of the incident angle. If you have say 5 m^2 of cells on your car, they have to be perpendicular to the sunlight to generate full power, which is going to be pretty hard to accomplish unless you're a stunt driver.

Bottom line is that under the best conditions, you may have one or two horsepower to work with. That may be enough to move a car at decent speed on the flat, but is going to reduce it to a turtle-like crawl on the uphills. (Yet another reason those solar races always seem to be held in the Australian outback - not a lot of hills there :-))

No, if you've got solar cells, the best thing you can do with them is leave them home, on the roof, where they're making power whenever the sun shines.

[Ryland]

Originally Posted by jamesqf

If you've got solar cells, the best thing you can do with them is leave them home, on the roof, where they're making power whenever the sun shines.

Right on! why put a technology that will last 50+ years on a vehicle that is designed to last less then 10 years and spend alot of it's time with a less then ideal angle to the sun.

it's poor use of a resource.
If you need to make a cross country trip take the train, for short trips charge at home.

[The Atomic Ass]

You could certainly use a car with solar panels on the road, just don't expect all your go power to come from them.

Zap offers it's truck with a solar panel option, which claims to give roughly 2 miles of electricity per day, or per hour of direct sunlight, I forget which. I can't think it's the latter, as that would require a very expensive solar panel indeed.

[jamesqf]

You could, but it would be a waste. I suppose it's the green equivalent of '50s tailfins & taillights shaped like rockets :-)

[jesse.rizzo]

I guess that's what I get for posting my speculations. Upon a little research, I found that only around 164 watts per square meter of sunlight reaches the ground. Even a 100% efficient PV cell couldn't power a typical road ready car. So, yeah. What those guys said.