Electric buses

King County Metro is testing all-electric buses in the Eastside, with hopes to use them to increase transit service without increasing greenhouse emissions.

There are several trolly buses (ones which use poles to get power from overhead wires), but these new buses will run on batteries, charging at special stations which will presumably be positioned where the bus turns around.

The system already runs hybrid buses, but they don't get much of a range boost from the batteries. I'm assuming that has to do with the weight of the buses and the amount of current draw needed from the batteries, which would be pretty large to store a meaningful amount of energy.

The new battery-powered buses are supposed to be able to go 23 miles or more between charges. They have composite bodies, which would lower the curb weight significantly, helping with efficiency.

Thirty-eight seats are on the bus, so there could be over fifty people on the bus during peak times. Hopefully, the range of the bus and the route length (in addition to compensating for a lot of traffic) were taken into account. Both of the Bellevue test routes are quite short.

Another interesting item is the charging station, which is wireless. The driver positions the bus and waits ten minutes. You'd think that charging would be a lot faster with a direct connection, but having something that would work thousands of times in all sorts of weather may be more trouble than it's worth. The other thing is the ten minutes itself; many drivers seem to use the turnaround to make up time so they don't get further behind if each time through a route they're behind schedule. The article does say charging could take less than ten minutes, or even if the buses will get charged at the end of each route.

Despite all those questions, it's going to be very interesting to see how the new buses work out, and how widely Metro is going to be able to deploy them.