Not because the vehicles are fancy. They are made from molded plastic, aluminum and honeycomb panels. They also have what amounts to a solar-powered gas station on the roof and sport comfortable-looking seats inside.

Even so, "they catch a lot of people's attention," said Schoenberg, a retired bioengineering professor from the University of Utah and owner of Sunzeecar LLC, which manufactures the solar-powered, single passenger Ekotrike.

Schoenberg welcomes the attention to his product.

"Anyone concerned about the high price for fossil fuels and air pollution should be interested," he said.

The Ekotrike achieves a zero-emission status through the use of solar-charged batteries and a pedal-driven electric generator. An afternoon of basking in the sunlight makes the Ekotrike good for traveling up to 40 miles at 20 to 30 mph on a single charge.

A trip to the U., which is about nine miles from the Schoenberg home, takes close to 30 minutes driving along side streets. A trip to the grocery store depends on how many people stop him or his wife, Mieke, in the parking lot to ask questions.

"People are so shocked, they usually slow down," Mieke said. "When I'm . . . at the store, it's rare when no one stops to look."

The Ekotrike is not meant to replace a car for trips more than 40 miles, and it's not equipped to tote more than one passenger or heavy loads. Its small size and low operational costs make it a great vehicle for short commutes around town. For one thing, the Ekotrike requires about half the parking space of a conventional car. It also operates at a range at least one-fifth that of a conventional car.

Schoenberg has spent about 12 years developing the Ekotrike, an effort that has been fueled by his desire to curb pollution, put the brakes on global warming and help the environment.

"Our transportation system [in the U.S.] is an atrocity, and unfortunately we've grown to accept that," he said. "As an engineer, I knew there was something I could do."

He also likes the challenge, said Mieke Schoenberg. "They provide a practical application of solar energy, and he gets to try them out."

Schoenberg has a few Ekotrike models, which can be seen banked alongside his home near the mouth of Millcreek Canyon. All of them are painted in bright colors for obvious safety reasons, and seat belts are standard on the vehicles. Two of the models have hub motors, while the other model features motors external to the frame. All are licensed in Utah as street-legal electric "motorcycles."

Schoenberg aims to modify the street-legal prototype Ecotrike into an attractive and commercially viable vehicle that he can sell in kit form. Planned advances in design and performance include making a two-passenger model and using lithium-ion batteries to charge the batteries more quickly.

Schoenberg believes the future is bright for his alternative mode of transportation.

"People will start to realize that we can't continue our gas-guzzling ways," he said.

For his part, U. graduate student David Estes touted another of the Ecotrike's virtues during his recent test drive.

"They're sure a lot of fun," he said.

Learn more

* For more information about the Ekotrike, call 801-274-7423, or visit web.mac.com/sunzeecar.