Can You Get More out of Your Hybrid? A tiny group of enthusiasts in California say they've demonstrated how to push your Prius to get as many as 99.9 miles per gallon -- if you're willing to plug it in overnight. Toyota says that although the idea is intriguing, it's not ready for prime time.

Can You Get More out of Your Hybrid?

  • Download
  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript


From NPR News, this is ALL THINGS CONSIDERED. I'm Robert Siegel.


And I'm Michele Norris.

50 miles a gallon is not uncommon for hybrid owners. But for a handful of tinkerers in California, 50 miles per gallon is nothing. They say they've doubled the fuel efficiency of a Toyota Prius with the help of an extension cord. NPR's Martin Kaste reports.

MARTIN KASTE reporting:

Electrical engineer Ron Gremban has been dreaming about electric cars since at least 1968, when he and some other Caltech students took on MIT in a cross-country race.

Mr. RON GREMBAN (Former Student, California Institute of Technology): It took eight and three quarters days to drive, day and night, across the country electrically. And the three of us in the Caltech team became the first three people to cross the continent on electric power.

KASTE: The Caltech vehicle was a VW bus, loaded with 2,000 pounds of batteries. Very 1960's, but not quite ready for the showroom. In the decade since, Gremban has been trying to find ways to bring electric cars to the American consumer, but he could never figure out how to raise enough money to do the job right. But now, as he drives his 2004 Prius around San Francisco, it would seem Toyota has done the job for him.

Mr. GREMBAN: Oh, this is a dramatically nicer car.

KASTE: Actually, Toyota has done most of the job.

Mr. GREMBAN: Basically, we've got a really good mass produced car that we just made minor changes to, to make it much more electric centric.

KASTE: Gremban has added a plug. Hybrids aren't supposed to have plugs. They charge their batteries internally from the engine and the brakes. But Gremban says, why not charge it even more? By replacing a computer and installing bigger batteries, he's made a Prius that doesn't bother to turn on its gasoline engine until you hit 34 miles an hour. The result is a dashboard display with some pretty impressive numbers.

Mr. GREMBAN: Look at the mileage right now. We've got, we've gone three miles. We've got an average of 93.8 miles per gallon.

KASTE: Gremban helps run a nonprofit called CalCars, which is trying to convince car companies to build plug-ins. The group says such cars could cut oil use dramatically, shifting much of our transportation energy needs to the electrical grid. They say plug-ins are a lot cheaper to drive than regular hybrids, especially because most of the charging would happen at night when power is sold at off peak rates. Toyota's response to the hacked hybrids has been ambivalent, as best.

Ms. CINDY KNIGHT (Spokeswoman, Toyota): You can certainly make a vehicle that will run, but you can't necessarily make a vehicle that people will buy.

KASTE: Spokeswoman Cindy Knight says Toyota does not think the concept is ready for prime time, at least not until there's a technological breakthrough in batteries that are lighter, more durable and cheaper. She doesn't rule it out for Toyota, but she says the company also has to keep certain marketing concerns in mind.

Ms. KNIGHT: Toyota went to great lengths to address the drawbacks of battery vehicles so that people do not have to plug our hybrids in. And our customers tell us that that is one of the features they like about the vehicle, they don't have to plug it in.

Mr. FELIX KRAMER (Co-Founder, CalCars): We're turning that whole, you don't have to plug it in around, and we're saying you get to plug it in.

KASTE: Felix Kramer, a co-founder of CalCars, says the fact that plug-in hybrids have gas tanks, makes them more flexible than previous all-electric cars. Even if you forget to plug it in, he says, you can still drive to the mountains for the weekend.

Mr. KRAMER: It's about the open road and going wherever you want whenever you want. I kind of figured that electric vehicles aren't going to make it until I discovered plug-in hybrids, and I realize this is the best of both worlds.

KASTE: The catch, price. A company called EDrive Systems in Los Angeles will offer Prius plug-in packages starting this spring for as much as $12,000. Fans of the technology say drivers can make this money back and save gas. But it will be a good test of just how far hybrid drivers will go to goose that fuel efficiency number of the dashboard display.

Martin Kaste, NPR News.

Copyright © 2006 NPR. All rights reserved. Visit our website terms of use and permissions pages at for further information.

NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.