Chicago (IL) - This week the wheels began turning on the first cow-powered milk trucks in the United States at the World Agriculture Expo in Tulare, California. If you have an image of a team of cows pulling a truck along, well you'll be happy to know it's not quite like that.
Two trucks in the fleet which typically run on diesel fuel, have now been converted over and are utilizing biomethane gas from manure collected from 10,000 cows at Hilarides Dairy in Lindsay, California. The cows are capable of generating 226,000 cubic feet of biomethane every day, which is enough to reduce the diesel fuel consumption of Central Valley Farms by 650 gallons per day. This is enough to drive a big diesel truck across the United States and back at 10 miles per gallon.
The process isn't as revolting as it sounds. Manure from the dairy cattle is flushed into a covered lagoon digester where gobbling bacteria much it up, converting volatile solids into biogas which is then captured by the lagoon covers. The biogas is piped from the digester to an upgrading system. It is there where carbon dioxide, hydrogen sulfide and other impurities also produced by the bacteria are removed. The process yields very clean burning bio-methane.
The project was financed utilizing a $600,000 grant from the California Air Resources Board Alternative Fuel Incentive Program. At today's $2.50 per gallon diesel prices and the equivalent of 650 gallons generated per day, it would only take one year to recoup the full $600K.
Utilizing cow manure for the production of bio-methane reduces greenhouse gas emissions in two ways. First, burning biomethane produces less pollution than standard diesel fuel, and producing it cuts down on the amount of atmospheric methane which is released by manure alone.
Advocates of biomethane claim that the gas is capable of turning rural communities such as Lindsay California into alternative fuel producers. Manure from dairy cows across the nation could potentially generate enough fuel to power one million vehicles annually, which would significantly reduce carbon emissions. Based on today's daily fuel use, the program has the effect of removing 16 gasoline or diesel vehicles from the road.