Risk aversion and incomplete economic considerations cited in report.
Research recently completed by the Water Environment Research Foundation (WERF), Alexandria, Va., addresses why more U.S. wastewater treatment facilities do not harvest the biogas generated during wastewater treatment to power the plant operations or return power to the grid. Most often the answers are related to simple risk aversion or incomplete economic consideration rather than technical feasibility, the research report says. Titled “Barriers to Biogas Use for Renewable Energy (project number OWSO11C10),” the report is available at www.werf.org.
According to the research report, an increasingly large number of wastewater facilities further treat solids under conditions that produce biogas, or methane. Not employing that biogas for heat or energy recovery is a lost opportunity for cost savings and environmental benefits. Although a significant percent of wastewater treatment facilities generate biogas, less than ten percent have the proper equipment to generate electrical or thermal energy using that biogas. WERF’s researchers found that decision makers perceive that the payback period on investment in the proper equipment is too long. Needed capital investment is funneled toward other higher priority items.
“The largest, most widespread barriers are economic, related to higher priority demands on limited capital resources or to perceptions that the economics do not justify the investment,” states WERF Director of Research Daniel Woltering.
The WERF research report also explains how other policies regarding air permitting and energy incentives further impact use of this valuable resource. To help inform decision makers on the return on investment from use of biogas for energy recovery, WERF says it will publish a comparison of well-accepted financial methods for evaluating the business case for investing in combined heat and power as a companion to this research.