As more than two dozen alternative energy-powered cars, trucks and motorcycles sat in the sun preparing for the third annual Alternative Car and Transportation Expo in Santa Monica last Thursday, a worker at an Arco filling station across the street swapped gasoline prices on the station’s marquee providing the No. 1 reason for the annual event.

The expo has more than 80 companies as exhibitors, many of which are based in Los Angeles. It is an open-to-the public event that touts, as the name implies, alternative modes of transportation that require little or no fossil fuels. It draws about 10,000.

The expo has become popular enough that it will travel to Texas next month.

“The city of Austin came out to the expo last year and decided to host it as well,” Zan Dubin Scott, a spokeswoman for the event, said. “So we’re taking it on the road.”

The idea for the expo came from Rick Sikes, Santa Monica’s fleet superintendant. Sikes is responsible for the city of Santa Monica sporting one of the greenest municipal fleets in the nation. Eighty-five percent of the city’s vehicles powered by alternative or renewable fuels.

“The real effort of the expo is to get away from our dependence on oil,” Sikes said. “Events like these are fairly common for government and corporate buyers, but there are very, very few geared toward regular consumers.”

The event is hosted and sponsored by the city of Santa Monica and Los Angeles-based Platia Productions and draws about 10,000 spectators.

The expo has huge corporations as exhibitors, such as Honda Motor Co. and General Motors Corp., and tiny companies, such as a Santa Cruz company called Zero Motorcycles Inc., which makes electric motorcycles. The show displayed high-performance racecars made by Santa Monica-based Electric Custom Cars and an award-winning Danish bicycle called the trioBike that can turn into a stroller.

“This thing has grown so much over the past three years,” said Paul Pearson, owner of Electric Custom Cars. “It’s not a high-pressure convention type event. We’re all on the same team. Plus, it’s really fun.”