Small-scale biogas systems have collected methane from landfills, sewage plants, and farms for decades. Here in the US, biogas is finally catching up with modern techniques with the advent of third-party operators introducing more sophisticated technology to capture methane and pump it directly into pipelines.
Renewable methane or natural gas represents a significant mostly unexploited source of energy. Examples include the vast amounts methane generated by manure from some of the 2,300 hog farms in eastern North Carolina, biodigesters that can turn clusters of large California dairy farms into energy hubs, as well as diverting food waste from landfills and transforming it into vehicle and heating fuels.
According to a 2014 EPA study, the U.S. could support at least 13,000 biogas facilities, fed by manure, landfill gas, and biosolids from sewage treatment plants. Those facilities could produce over 650 billion cubic feet of biogas per year – enough renewable energy to power 3 million homes.
A study by the World Resources Institute estimated that the 50 million tons of organic waste sent to landfills or incinerated every year in the U.S. has the energy content of 6 billion gallons of diesel fuel, amounting to 15% of all diesel consumed by heavy-duty trucks and buses.
Utilizing all that biogas could help lower greenhouse gas emissions from some of the most difficult sectors to decarbonize – transportation, industry, and heating buildings. In addition, ramped up renewable gas could keep organic waste out of landfills and prevent manure runoff into rivers and water supplies.
Renewable natural gas could be the next big thing in green energy.
Photo, posted June 19, 2013, courtesy of Alan Levine via Flickr.