Busses are too few and at this time, generally do not lend themselves well to pure electric approaches.
Far more important are the large number of Commercial vehicles, esp. Semis.
About 3 years, O and the Dems tried to push a tax break that would enable us to move new commercial vehicles off diesel and over the nat gas. Sadly, the neo-cons/tea* fought that because the large oil companies do not want to see the price of oil plummet.
What is really needed is to drop the massive subsidies that we have on oil/nat gas/coal, and the moderate subsidies on hybrids and electric vehicles.
Instead, we should have a set of LIMITED TIME subsidy that solves a few of these issues:
1) for any pure electric car with a range of 100-149 MPC (via epa rating), they get 7.5K. For any pure electric with a range above 150 MPC, give them $15K.
This should drop by $1.5K each year.
2) a subsidy for any commercial vehicle using [LC] Nat Gas. In addition, if this is for a serial hybrid, the subsidy should start at the same amount (i.e. a serial hybrid using Nat Gas will have double subsidy what a simple nat gas truck would have. In addition, the large the vehicle, the more subsidy for it. Finally, the nat gas subsidy should drop by 20%, and the serial hybrid should start dropping after that. So, that means that the nat gas subsidy is gone after 5 years, and the hybrid portion will be a steady rate for the first 5 years, but then drop 20% for the next 5 years, meaning that it will last 10 years.
Commercial vehicles makers are ready to do nat gas. It will be expensive at first, but will drop rather quickly. It is the hybrid portion that is of interest since it allows a company to focus on creating pure electric vehicles down the road.