Will Carmakers and Drivers Warm Up to Solar-Powered Vehicles?


Pickup truck powered by solar panel. Photo by Gail Delaughter/KUHF

"Bouncy and peppy" is the way Houston electric car dealer Rick Ehrlich describes the small, three-wheeled pickup that sits outside his Houston electric car business.

"It's a funny little truck," adds Ehrlich as we take it for a spin around the parking lot.

It's a no-frills Zap pickup that weighs about 1800 pounds. It's doesn't look a lot different from the other vehicles at the Houston Electric Car Corporation, but what makes this one different is that you don't have to plug it in to a charging station to power it up. It gets all its power from the sun.

That funny little truck is powered by a lightweight 180-watt solar panel mounted over the bed, which feeds a battery that powers a small, quiet electric motor.  The truck only has a top speed of around 35 MPH and you can't drive it on the freeway, but it's legal everywhere else. Ehrlich says on a clear day you can go eight to ten miles just on the power of the sun, a bit further if you use the power stored in the battery, and it's perfect for people who drive 30 miles or less in a day.

As for the cost, Ehrlich says you can get an electric vehicle for as low as $6,000.  The solar panel costs another $1,000.

"To me, it sounds like nirvana, to find a car for $10,000, that you can drive up to 30 miles a day, virtually for free. When I say virtually for free, they cost between one and two cents a mile."

Erhlich adds, "I think if you go out and buy gasoline every week for your heavy vehicle, you're crazy."

But that's what most Houston drivers are still doing, and their cars and trucks can hardly be described as bouncy and peppy.  Large SUVs and heavy-duty pickups are the predominant vehicles on Houston's freeways.

University of Houston architecture professor Patrick Peters works extensively in solar design.   Along with developing green buildings with his graduate students, Peters is involved with a start-up company that develops solar-powered charging stations for electric vehicles.

Peters says interest is being generated by international solar vehicle competitions,  such as the American Solar Challenge.  While the aerodynamic competition vehicles aren't very practical for everyday use, Peters says these events lead to new technologies that can migrate into the commercial sphere, showing up in vehicle lines that target early adopters for new technology.   Mercedes,  for instance, uses a solar-powered ventilation system to help keep a vehicle's interior cool on hot days.  The Toyota Prius also has a solar-powered sunroof.

Peters is encouraged to see a totally solar-powered vehicle enter the marketplace, but to make the vehicles popular on a large scale,  car makers will have to find ways to integrate the solar panels into the body of the vehicle.  He says the panels also need to be included in a vehicle's warranty so they're not just an add-on part.

Developing lightweight materials to build solar-powered cars is also essential.  Peters says if you can build a bigger car with lighter materials, that will give you more surface space to collect sunlight.  There's also thin solar film that's currently used in various industrial applications.

"Those thin films can take the geometry of the vehicles that's required to maximize its aerodynamic qualities."

The first customers for hybrids, says Peters, were people who wanted to show their concern for the environment through their choice of vehicle. He expects it will be the same with solar cars.   Peters thinks more people will get interested once they start seeing solar vehicles on the roads.

And Peters says if gas prices continue to rise as some analysts predict,  Houston drivers will "respond to the pressures of pragmatic constraints" and take an interest in that funny little vehicle in their neighbor's driveway.

"When fuel costs go up, people get very interested in energy-efficient vehicles of every kind."