At the foothills of the Austrian Alps, dairy farmers and cheesemakers Toni and Martha Fahringer are bringing new meaning to the phrase “stinky cheese.”
Unlike many of their competitors, which depend on electricity or fossil fuels to power their homes and cheesemaking operations, the Fahringers use cow manure to supply the heat for the cheesemaking process.
The family owns 35 Simmental cows, fed on hay cut three times a year from the farm’s own fields. Because the animals’ stomachs can’t completely digest the grass, their dung contains plant matter that can be broken down even further in an anaerobic digester to produce methane gas.
When the cows are houses in their cozy shed, a collection of automatic scrapers deliver the cow dung into a massive concrete tank buried under the building. The gas is gathered and stored in a large flexible ‘bag’, which is housed and protected in a typical Austrian wooden shed a few metres away from the slurry tank.
The stored methane is burnt in a conventional central heating boiler, which has been adapted to burn the gas. This provides the majority of the heating requirements for the family and its cheesemaking business throughout the year.
With fuel prices rising all over the world, and claims that methane from cows is responsible for 18 percent of all greenhouse gas emissions, utilizing bovine waste in this manner could be a way to solve two problems at once.
Last year China’s Huishan Dairy became home to the world’s largest system for generating electricity by collecting methane gas emitted by fermenting cow manure. GE supplied the project’s gas-powered generators, and hopes that the effort will showcase the large-scale possibilities of the technology (MIT Technology Review).
Recently, a group of researchers at the Harvard School of Engineering and Applied Sciences (SEAS) demonstrated a methane-fueled micro-solid oxide fuel cell that was able to operate at much lower temperatures than many scientists thought was possible. Some believe that this fuel-cell technology could be the secret to harnessing methane energy for common electronics.
Image Credit: Flickr - andyarthur