For Swedish automaker Volvo, the combustible engine in a thing of the past. Beginning in 2019 all of the new car models it introduces will be fully electric or hybrids. It's the first major traditional automaker to set a concrete date for phasing out combustion-engine-only models. The trend, however, isn't limited to just car companies. There is a boom in electric bus manufacturers in the U.S. as well, including right here in Southern California.