Anaerobic Digester Project and System Modifications: An Economic Analysis

This Washington State University Extension publication examines the economic considerations associated with developing and operating anaerobic digestion systems for dairy manure management. The report introduces key project components and evaluates the profitability of different anaerobic digester configurations, including combined heat and power systems, boiler-based systems, and renewable natural gas infrastructure.

The publication reviews typical capital costs, operating costs, and potential revenue sources associated with digester projects, emphasizing how policy incentives and energy markets influence financial performance. It also discusses how environmental incentives such as carbon credits and Renewable Fuel Standard credits may substantially affect project viability.

Using modeled financial scenarios, the report compares net present value and benefit-cost ratios under varying assumptions about renewable natural gas markets and environmental credit retention. The analysis highlights how both system configuration and policy incentives can strongly influence whether an anaerobic digester project becomes economically viable for dairy operations.