Detroit Auto Show: GM's Belt Alternator Starter Hybrid System

DETROIT, Jan. 6, 2003; General Motors has developed a simple solution to making hybrid-electric powertrain technology available to more types of cars, trucks, and sport utility vehicles, the company announced today at the North American International Auto Show. GM engineers developed the belt alternator starter system (BAS) to provide improved fuel economy in stop-and-go driving by shutting the engine off at idle mode and by enabling early fuel cutoff to the engine during decelerations. The system combines sophisticated engine controls with GM's VTi variable transmission and a precision electric motor/generator. Regenerative braking and efficient charging are also part of this system. Estimated EPA composite fuel economy savings range from 12 percent to 15 percent. Other benefits of the belt alternator starter system include the versatility to use the system on four- and six-cylinder engines, with minimal impact on engine and transmission architectures. Electric power comes from a single 36-volt battery while maintaining the present 12-volt electrical system. All vehicle accessories and passenger comfort systems, such as air conditioning, remain functional during the periods when the engine is automatically stopped.