This post originally appeared on Orphan Road.

I thought it was a settled case that Metro’s new hybrid buses were no more fuel-efficient than the diesels they replaced. Now comes an article in Truck Trend (I’m sure yours is in the mail…) citing a government study (PDF) that shows the opposite.

The real-world study, conducted in Seattle in 2006, shows a 27% increase in fuel economy over the old buses. It’s hard to say what accounts for the disparity, although it appears from the study that actual fuel economy for both bus types was lower, and thus the difference more dramatic. Either way, it’s good news King County.

(Incidentally, the study was provided by the National Renewable Energy Laboratory. There’s a funny story about President Bush’s visit to NREL last year.)