In lay person terms, anaerobic digestion systems create a vacuum for food and other organic matter to quickly decompose without air (anaerobic). Methane gas is generated in the controlled environment and used to produce natural gas, condensed natural gas (CNG) or electricity. Food breaking down in landfills also produces methane gas yet in an uncontrolled environment. Even when gas is collected at a landfill, the majority of the methane escapes as a greenhouse gas, 20 -25 times more potent than carbon dioxide.
Traditional commercial composting operations include the use of windrows (piles of food residuals & yard trimmings|wood chips) where the organics decompose in an aerobic (with air) environment due to "turning the windrows" at regular intervals and the passive movement of air through the piles. Well-managed composting operations do not produce methane gas.
|EISENMANN plant rendering|
|Commercial food waste - a powerful|
In addition to securing the facility feedstock, W2E has a long-term Power Purchase Agreement with Santee Cooper, SC's state-owned electric and water utility, to purchase the electricity produced from the methane gas generated at the facility.
Read the September 01, 2011 Eisenmann press release for additional details on the W2E Columbia, SC project announcement.
|Daniel @ POWER|
With strong synergies, Ei|ZWZ plans to work closely with Daniel and his team as he uses the Columbia flagship facility to develop a template for a series of systems throughout the Southeast. Follow the ZWZ Blog to keep current on the milestones achieved in diverting organics from landfills and to energy use.