An Internal combustion engine and a motor/alternator
From Christine & Scott Gable, former About.com Guide
On the left is the efficient ECOTEC engine. Right is the power inverter for electric power control. This system employs a high-tension belt driven starter/alternator to start the engine and give mild assist. GM calls it BAS (Belt Alternator Starter).
photo © Adrian Gable©2009 About.com, a part of The New York Times Company.
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