CHP is a reliable, cost-effective option for wastewater treatment facilities (WWTFs) that have, or are planning to install, anaerobic digesters. Biogas produced by the digesters can be used as “free” fuel to generate electricity in a CHP system using a turbine, microturbine, fuel cell, or reciprocating engine. The thermal energy produced by the CHP system is often used to meet digester heat loads and for space heating. A well-designed CHP system offers many benefits for a WWTF because it:
• Produces power at a cost below retail electricity,
• Displaces purchased fuels for thermal needs,
• Qualifies as a renewable fuel for green power programs,
• Enhances power reliability for the plant, and
• Offers an opportunity to reduce greenhouse gas and other air emissions.