Thursday, August 7, 2008


The fodder-chopper churned outside the barn yesterday. Cornstalk grinding has a special place in my heart because it was one of the first jobs I did at Howell Farm when I visited back in January. You can read about that experience here:

In the pictures below, you can see that a belt connects the chopper to a stationary hit-and-miss engine, which provides the power. The engine runs off gasoline.

Farmer Rob (who is also a trained physicist) says that on the sustainable farm of the future, he thinks stationary engines will still have a place – for jobs like threshing and corn shelling. The difference, from a sustainability standpoint, is that these engines will run off bio-gas processed on the farm from the release of methane from manure.

My first thought on this was, if you’re going to run a stationary engine off bio-gas, why not just run a tractor with a PTO off bio-gas? Rob says that the problem with gas is that it’s diffuse – hard to store in a reasonably sized tank on a vehicle that needs to be mobile such as a tractor.

All true, but I’m still pulling for do-it-all, bio-gas powered tractors. By the time bio-gas engines are ready for primetime, maybe the technology of methane gas compression and storage will also have hit its golden age.

According to Wikipedia:

“If concentrated and compressed, [biogas] can also be used in vehicle transportation. Compressed biogas is becoming widely used in Sweden, Switzerland and Germany. A biogas-powered train has been in service in Sweden since 2005.”