In response to recent blog posts, a British biogas expert and businessman named John Baldwin has sent us several links on biogas use in internal combustion engines, including the afore-mentioned bus system in Lille. I recommend the movie. Apart from showing how the system works, it gave me chance to remember some O-level French.
The main problems in vehicular biogas seem to be cleaning up the gas and compression to a denser fuel for efficient transfer. But, as the gas once sufficiently clean is equivalent to compressed natural gas, already widely used as a vehicle fuel for city fleets because it's clean-burning, relatively cheap, and reduces maintenance costs, there's not as much fuel supply risk to buying a gas-powered fleet as you might think. It's easy to see how a mixture of regular natural gas and biogas can be used to recycle organic waste efficiently and reduce city air pollution.
Thanks very much for your interest in our little project!
From Mr. Baldwin:
Good video here:
Lille video attached....
MD, CNG Services Ltd