Excellent as usual. Only Zamboni makes a Zamboni.
http://en.wikipedia.org/wiki/Ice_resurfacer
During the 2010 Vancouver Winter Olympics, serious problems developed with the three battery-powered “green” resurfacers used to maintain the speed skating oval, products of Canadian-owned Resurfice. Malfunctions included ineffective waste-ice storage and significant tire gouging; in order to improve the ice a propane-powered Zamboni brand machine was brought in from Calgary’s two-decades old speed skating facility, site of Canada’s last Winter Olympics.[2] Speed skating figures from outside Canada speculated such widespread mechanical issues might be due to the restrictive international access policy since the Richmond Olympic Oval was constructed 18 months ago, with the resurfacers unable to complete their break-in process due to relatively infrequent usage.[3]
It was not all that long ago that propane would have been considered very green. But now with globull warming, the story has changed. As for those batteries, it isn’t all that green an undertaking to make them.