Experimental Hybrid Cars Get Up to 250 Mpg

By TIM MOLLOY, Associated Press Writer

CORTE MADERA, Calif. - Politicians and automakers say a car that can both reduce greenhouse gases and free America from its reliance on foreign oil is years or even decades away. Ron Gremban says such a car is parked in his garage.

It looks like a typical Toyota Prius hybrid, but in the trunk sits an 80-miles-per-gallon secret — a stack of 18 brick-sized batteries that boosts the car's high mileage with an extra electrical charge so it can burn even less fuel.

Gremban, an electrical engineer and committed environmentalist, spent several months and $3,000 tinkering with his car.

Like all hybrids, his Prius increases fuel efficiency by harnessing small amounts of electricity generated during braking and coasting. The extra batteries let him store extra power by plugging the car into a wall outlet at his home in this San Francisco suburb — all for about a quarter...

Monrovia-based Energy CS has converted two Priuses to get up to 230 mpg by using powerful lithium ion batteries. It is forming a new company, EDrive Systems, that will convert hybrids to plug-ins for about $12,000 starting next year, company vice president Greg Hanssen said.

Read the rest in YahooNews.