The cost-benefit analysis presented within this report is a high-level, concept feasibility study and is not a detailed design or detailed cost estimate.
At the design COD loading and design biomethane production potential where all biogas is used to off-set natural gas at $12/GJ, the COHRAL could deliver an IRR of 8.3%.
A biogas fired reciprocating cogeneration engine in conjunction with the COHRAL (466 kWe power output with associated renewable energy credits) could deliver an IRR of 11.7% when operating at design capacity. Considering a biogas engine in isolation and accounting for the opportunity cost of not using current rates of biogas production in a boiler, an engine could deliver an IRR of 69% (~3-year payback). However, via the use of equipment financing it is possible for the monthly net cash flow to be positive thereby improving the IRR even further, hence trending towards an “instantaneous” payback.