First Bus in Norwich decided to become slightly greener by running more of their fleet on bio diesel. There is, however, a major problem with the bio diesel they use. It freezes and won't work in sub zero temperatures.
There is though good news on the horizon. With global warming sub zero tempertures will soon be a thing of the past so the buses running on bio diesel will no longer have this problem. I knew global warming would be good for something.
P.S. Yes, I am joking about global warming being a good thing.