Power from cow manure?

Project BLUElab members  at the University of Michigan are developing a more efficient “biodigester.” According to AIDG (Appropriate Infrastructure Development Group),  biodigesters convert organic wastes into a nutrient rich liquid fertilizer and biogas, a renewable source of electrical and heat energy.”

Biodigesters are also very environmentally friendly, as it provides a way to dispose of animal and human waste. AIDG explains, “(the) waste is processed in a biodigester, it is sterilized by methane-producing bacteria and the high-methane environment, causing bacteria to be killed. The effluent that remains after gas production is a high quality organic fertilizer that can be safely used on food crops. Families, for whom AIDG has installed biodigesters, have reported seeing the quality of their crops improve dramatically after only one year of using biodigester fertilizer”.

The University of Michigan engineers are hoping to develop better biodigesters  to fuel stoves with biogas and distribute it in other countries that don’t necessarily use electricity or gas to cook. In addition to providing fuel, these systems offer an environmentally friendly way of treating waste. BLUElab members are working towards solving development problems both domestically and internationally and are hoping that this project expands to other areas to use this environmentally-friendly power source to fuel other works.

A great example of how biogas can be used as a major energy source is the Blue Spruce Farms located in Bridport, Vermont. This farm uses their animals to fuel their electricity-they are actually getting their power source from cows! According to the article “Cow Power,” the cows, or more specifically cow manure, is generating power for this farm. It seems like there would be an endless supply, as one cow can produce 30 gallons of manure each day. The 1000 cows and counting at Blue Spruce Farm are a power source waiting to be tapped.

To create the methane gas that helps power the farm’s generators, the cow manure is first pushed into a 600-gallon concrete tank kept at 101 degrees Fahrenheit. The reason for this is to maintain the temperature of a cow’s stomach, so that the bacteria in the tank can continue the processing cycle of the manure and produce the methane gas that powers the farm’s generators.