Brown Gold: Methane Digesters and You

by Andrea Millar — April 2, 2008

There are many ways we're adapting ourselves to the current energy concerns. Car makers receive subsidies for new leaps in fuel economy. Corn farmers are throwing themselves into the ethanol fray with gusto. Solar panels become more and more cost-effective and feasible as technology advances. But all these have their complications and drawbacks. Car manufacturers still haven't figured out an efficient, cheap alternative to substantial fuel consumption (as the $22,000 price tag on the Prius attests). Wheat prices are skyrocketing as farmers switch to more commercially viable corn. And solar panels are fantastic--if it's sunny out. It's rare, if not impossible, to find a perfect solution.

Enter biogas. While far from perfect, technology is finally available--and feasible--to offset the large carbon footprint made by the dairy industry. With large, tented "digesters," manure enters in one end, and electricity producing methane exits, thanks to the use of anaerobic bacteria, the type that grow in the absence of oxygen. The leftovers are an odorless fertilizer, deemed safe for use on crops for its near-elimination of fecal coliform bacteria--a good thing to keep out of, say, your groundwater when runoff from rain occurs.

Sound too good to be true? Not too good for Tillamook, Oregon. Yes, that Tillamook. The same farmers that supply milk for the famous cheese have been utilizing a digester since 2003. Other dairies are slowly jumping on board as well. If you're lucky enough to have organically-produced Clover Farmstead Butter on your shelves, know that its production is powered entirely by homemade methane biogas.

What's holding this technology back? Primarily, lack of funding. The energy, while abundant, is slightly more expensive to produce for the consumer. The manure needs to be consolidated, hauled, and processed, all of which cost time and manpower. And the initial investment can run in the millions. Still, the triple package of capturing methane emissions, electricity production, and safer fertilizers definitely puts methane digesters in the black for possible energy and pollution management.