"The only thing RE's might do is slow the growth of CFE generated GHG."

- There. You said it. That's the point exactly!

As far as Energy Balance, this has been reintroduced here regularly, so you can look it up yourself (Google NREL), but Solar Electric {PV) HAS been evaluated as recovering its Embodied Manufacturing and Materials Energy within the first year or three, depending on the panel type, while continuing to be productive for two to three DECADES afterwards, and being highly recyclable thereafter. No moving parts, can sit on the rooftops or BECOME the rooftops, which were expensive to build in their own rights.. and not bother anybody. As 'imperfect' and 'mortal' technologies go, PV has a lot going for it.

Finally, you said;

"The Solar panels really don't run the bus, they are just offsetting the power drawn down by the bus when it plugs in."

What's the difference? This is misleading. If these panels are Grid-tied, they are putting watts into the grid and the bus is taking them back out.. not the 'same watts' per se, just like the dollars you put into the economy are not necessarily the same ones you get back when you are paid for your work, but what's the difference? You seem to be implying that the inputs from this system 'aren't really' covering the draws on it, or at least your statement could easily be read that way..

The point is that PV panels (or Wind, etc) CAN run a bus, provided you've installed enough of them. The details of Charging, Battery Transfers or whatever is done to get that charge onto the bus is worth knowing, but is not such a dramatic challenge as you suggest. Even the transfer of a New Battery Pack every few hours (the article said the Zebras give them a 200km or 120mile range), while cumbersome would hardly have to be an extreme engineering challenge, though I would expect that the future really will lie with Trolley Buses as Alan Drake includes in his 'Light Rail Now' plan for transp. http://www.lightrailnow.org/features/f_lrt_2006-05a.htm .. but that said, the solutions will take on many varying forms, and Battery Buses can certainly have a place in that.

Bob Fiske
Snowed in in Maine!