By electric bus systems, I assume you mean hybrid buses. Fully electric buses are being developed, but again they suffer from the same problems as the electric car. There's next to no range on them. Hybrid electric buses still have diesel engines in them. When they run, they still make noise just like the diesel bus. All we've seen from the analysis of hybrid electric buses is that you get approximately a 5% improvement in fuel economy. There's not a great deal more than that. A saving economy of 5% for a $200,000 premium on a bus just seems a little excessive. Those numbers came from the engine suppliers. One of them was BAE and the other one was Allison.
Those areas just meant that we weren't looking at the hybrid buses much deeper than that. We have done trials. Calgary Transit has hybrid electric vehicles on a smaller scale, for small trucks and cars to see what we get out of those. The numbers are pretty much borne out, really. It didn't seem to be an alternative that was worth pursuing too aggressively.
CNG did provide a bus that was quieter and possibly even quieter than a hybrid bus at certain speeds. It does have maintenance advantages over a regular diesel bus compared to the systems that are on right now. The environmental code means that a certain amount of exhaust processing has to happen with filters and various other systems that are expensive to maintain and expensive to install. They are not needed on the CNG bus.
We did look at an alternative of LNG.