The San Francisco Chronicle took a test drive of one of the nation's few plug-in Toyota Prius models, and -- not surprisingly -- one of the most striking features of the car was what it didn't have: Engine noise.
The car's owner converted a 2004 hybrid into a plug in by swapping out its metal hydride battery for a lithium-ion battery. Cost: $15,000.
That's a steep price to pay for quiet, but it's a prototype. Car makers around the world are working to improve the battery technology, bring down costs and make these cars widely available.
That effort will be key, according to a recent Natural Resources Defense Council report, as controlling pollution from a handful of power plants -- which supply the electricity that helps the plug-in hybrids go -- will be easier than controlling the tailpipe emissions from millions of cars.
With the twin issues of global warming and energy independence in mind, getting a lid on oil consumption in the nation's vehicle fleet gives this test drive something to shout about.
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