I note that there is a topic in this section about electric buses to be made in California
The city of Denver has had hybrid buses for several years which run on the 16th Street Mall Shuttle. They are quiet and fairly slow but very popular and I took a short trip on one.
They recharge their batteries from a small on-board i.c.engine, but whenever these start up they emit a cloud of exhaust fumes, typical of a cold start, unfortunately defeating the original intention.
The RTD are now testing a new generation of hybrids using lithium ion batteries. Further details are at
http://www.rtd-denver.com/FF-CleanAir.shtmlElectric propulsion is of course the cleanest but one has to reflect that somewhere a power station is operating burning fossil fuel.
