Bwis53 wrote:Didn't the City of Madison or UW have service vehicles running on some alternative fuel? There was a big deal made about it in the news. I just wish I could remember the silver logo on the back of the vehicle as it was driving down State St.
Don't know about Madison in particular but propane makes a fairly good motor fuel. It burns in a regular engine with slight modifications to the fuel system. Because it is liquid under pressure it can be fairly energy dense, though not as much as gasoline
Problems are the size of the tank. The propane tank winds up taking about 25% of a pickup truck bed to give almost the same range as a gas tank. It is also heavy which leads to poorer milage.
And in Wisconsin, in winter, the propane would need to be heated to gasify it.
Back in the 80's the plant where I worked had 3-4 standby generators, 50KW or so range, and we powered them all with propane.
6-7 years ago I sat next to a farmer from either Minnesota or Wisconsin on a plane and we got talking. He had several thousand cows and collected all their manure, fed it into digesters and generated enough methane to run 5 1MW Caterpillar generators. He used a bit of the power to run the farm and sold the rest back to the power company. He used the heat from the exhaust, radiator and oil cooler to keep the digesters warm and fermenting. Also for building heat and hot water. His big complaint was that he was wasting about half the heat because he had no way to use it.
There is, or was back in the 80s and 90s a hell of a lot of energy being generated in the US from manure. There may still be but I have not kept up on it and with gas prices so low, it might not still be viable.