Bikes & Cars...

Brothers Chris and Andrew Ewert of Wheaton, Illinois, converted their standard-issue Prius to a plug-in hybrid that gets more than 100 miles per gallon by installing a battery array and charger in the rear cargo space. Cars with plugs and gas tanks, called Plug-In Hybrid Electric Vehicles (PHEVs), are on the bleeding edge of auto technology, but the Ewerts aren't alone in their low-emissions mission.

In a recent interview with Chicago's CBS 2 News, Chris Ewert challenged auto makers: "My brother and I built this, and car companies should be able to do it, too." Fear not, Chris. Toyota brought a plug-in hybrid Prius to the Detroit auto show in January, and the boys at Cars.com even got to test drive one of the rare beasts. Of the few PHEV Priuses in the U.S., four are in the hands of UC Berkeley and Irvine's Clean Mobility Partnership.

If you have a hybrid but not the Ewert brothers' engineering know-how, fear not. Hymotion has developed a PHEV conversion kit for second-generation (2004-2008) Priuses that sells for $9,995 with a 3-year warranty. The company promises 100 mpg for 30-40 miles, and will help you locate an installer in your area.

Hybrids Plus will convert a Toyota Prius or a Ford Escape hybrid to PHEV today, with the Toyota Highlander hybrid coming online soon. (The Escape conversion works on the Mercury Mariner and Mazda Tribute hybrids, too.) Prices for the conversion, which are all done at company HQ in Boulder, Colorado, range from about $21,000 to $36,000.

Image courtesy of Hybrids Plus. Note that this is not how your converted PHEV will look.

Want to learn more about the Toyota Prius?

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