Friday 17 December 2010

Electric Buses

Start and stop fixed loop delivery vehicles are a prime candidate in the logistical supply chain for electrification. In previous posts I've pointed that out and also the accumulating evidence that the marketplace is starting to take notice. Specifically that those kinds of applications are already cost competitive with diesel and if prices rise drastically post peak oil decline then they will become more cost competitive still.

What about buses? I've pointed out before that buses are another prime candidate for electrification since they are fixed loop and since there is typically a large dedicated depot facility at the beginning/end of the loop, that depot facility would be a prime candidate for a fast charge facility so that even in heavily used urban bus routes, the bus could be taken out of service for, say, an hour and fast-charged back to 80% of capacity. I expected that this would cover most if not all urban bus scenarios.

As it turns out, I'm way too pessimistic. In the US, which has some 800,000 buses registered, close to 75% of them travel less than 100 miles per day. This is particularly true of the nearly 500,000 school buses.

There are several bus companies who have either hybrid, plug-in hybrid or fully electric already in short-run production.

One interesting application is one recently trialed by GE Global Research who have successfully piloted a dual battery system which has two distinct kinds of battery technologies: One is a high power A123Systems advanced (but expensive) lithium-ion battery with extremely high power density and the other is a much less expensive sodium metal halide battery which has lower power density but higher energy density.

The combination of the two is both cheaper (20% less expensive) - making it an easier sell - and meets the needs of a stop-and-start transit application or else a school bus type application.

I make that to be a potential market of more than half a million vehicles at the same time as shoring up yet another section of the transportation network.
Since these are a 1:1 substitution for diesel applications, the diesel that these electric vehicles *would have* used would subsequently be freed up by use forpersonal transportation, thus blunting any potential price rises and allowing car manufacturers a longer time period to amortize older plant and equipment and also spread the costs of raising capital for new plant and equipment.

So now where are we post peak oil in terms of substitutes:

Long distance transportation (via electric rail) Check.
Long distance shipping via nuclear powered freighters. Check.
Hub and Spoke last mile delivery via electric trucks. Check.
Pizza delivery via electric scooter. Check.
Mass transit via electric buses. Check.
School Transit via electric buses. Check.

The only remaining piece is to cover the personal transportation segment.

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