Operations & Maintenance
Experienced farmers and farm staff already have the right skills for managing and operating a digester system. Daily experience with animal nutrition and health is a good foundation for understanding digester feeding and system troubleshooting. Experienced RCM field staff is onsite during project construction and start-up to provide one-on-one training in digester operations, maintenance and trouble shooting.
Daily farm mechanical maintenance of manure pumps and mixers and tractor engine maintenance are the mechanical skill and understanding necessary to operate a digester engine.
A properly running anaerobic digester project will take no more attention than a 30-minute walk around to check the engine and biogas meters, digester pH and temperature.
In an instance where a manure pump gets clogged with a foreign part or the engine needs attention, more time will be needed.
Operations and Maintenance costs usually range between $0.02- $0.03 per kWh of power generated by the project. For instance, a 100 kW engine-generator running 90% of the time could produce 788,400 kWh each year which would cost between $15,800 – $ 23,652 per year to maintain and operate.
Costs are incurred by:
- Labor and materials for routine digester checks and engine maintenance such as oil and spark plug changes.
- Oil changes on the engine are required every two weeks which can require additional labor hours.
- A top-end rebuild of the engine about every 20,000 hours (2.2 years), which can cost about $10,000. A good mechanic can do the project in a day.
- Engine Heads need to be replaced every 8,000 to 12,000 hrs. These are easily replaced in one day.