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The U.K.'s AutoCar reports, "Mazda engineers are hard at work trying to develop a rival to the Chevrolet Volt."
All hybrids currently for sale in the U.S. are parallel hybrids -- their electric motors work to improve the mileage of their gasoline engines, but the gasoline engines do the bulk of the work of moving the car. The Volt is a series hybrid -- its electric motor can power the car alone, with its gasoline engine activating only when it needs to recharge the car's batteries. AutoCar reports that Mazda is developing a series hybrid.
"Senior sources say that trials are currently underway in Japan, with a prototype that uses a rotary engine to charge the battery pack. The tests are sufficiently advanced that Mazda has a working prototype in a Mazda 5 MPV bodyshell." But while the company is "said to be keen to put this system into production… no firm decisions will be made until the cost of batteries is reduced."
Mazda's prototype apparently uses a rotary engine (also known as a Wankel engine) to recharge the car's batteries. Mazda is the only major manufacturer to produce a rotary engine, currently sold in the RX-8, which some enthusiasts believe accelerates more smoothly than the more common cylinder-based engines. Autoblog comments, "We …find it odd that Mazda would use a rotary engine in this setup. While the Wankel engine is very compact and light, it's not very efficient and sucks oil, at least in the RX-8."
EcoGeek may have figured out why Mazda would be using a rotary engine in a hybrid, however. They note that "Wankel rotary engines are much smaller and lighter than piston engines, and so will be less of a burden to haul around while the car doesn't need it."
Whatever the motivation, Wired notes Mazda's efforts could change the hybrid arms race significantly. "What makes this especially interesting is Ford owns Mazda, which means anything Mazda builds could appear in showrooms with a blue oval on the hood." Many analysts had believed that Ford was significantly behind GM in hybrid development, perhaps even looking to partner with its rival in order to catch up. If Mazda is developing a series hybrid, that may not be the case for long.
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