Conventional gasoline-powered and hybrid vehicles undergo all sorts of boundary-pushing tests before hitting showrooms, but this kind of testing is still new for plug-in hybrids like the Chevrolet Volt, which has yet to be released. According to GM, the Volt has performed well in a variety of grueling scenarios.
Among the tests performed so far at the General Motors Desert Proving Grounds in Yuma, Arizona: the Hot Soak Evaluation, where the Volt is "baked" in the sun for several hours before the car is taken for a spin and the air-conditioning is tested out; Grade Load testing, where engineers simulate endless hill and mountain climbing with a towing dynamometer to see how well the Volt performs in an uphill climb at over 100 F; and the Trailing Dust Test, which involves a Volt driving behind a dust-kicking Chevy Silverado for about 12.2 miles. Engineers check for dust through the Volt's door seals, air filter, and other filtrations systems.
While these tests are standard for most vehicles, they are especially important for plug-in hybrids, which have different features and needs than pure gasoline-powered cars. The Volt, for example, features "Mountain Mode"—an option for drivers who know that they are about to climb a big hill that draws an energy reserve in the lithium-ion battery so that the vehicle is boosted by the full power of both the gasoline engine and the electric powertrain. And if drivers can't use Mountain Mode in the hilly desert, that makes GM look really, really bad. All of which is why this kind of testing is necessary if the Volt wants to succeed in the untested waters of the PHEV world. The next step: actually selling enough cars.