VAAFM - Anaerobic Digestion Technology - Biogas Engine/Generator Technology

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Anaerobic Digestion Technology - Biogas Engine/Generator Technology

Traditionally, the generators that run on biogas have been adapted internal combustion engines with an attached generator. Sterling engines with their external combustion systems and microturbine generators also show promise. Sterling engines can burn any quality of gas that is combustible, but they are still new to the market place. Microturbines have the advantage of having only one moving part in the engine, but have had serious problems on the farms that have tried using them due to problems with compressing “un-scrubbed” biogas. To make a microturbine work, a gas scrubbing system will probably need to be installed, to remove hydrogen sulfide from the biogas. Currently the maintenance of that system outweighs the advantages of the microturbine. In the future fuel cells may also play a significant role if the technology can over come the purity issues. The advantage a fuel cell has over any other technology for generation is that it has no moving parts so should require the least maintenance. For very large biogas combustion systems, where combined heat and power is feasible, steam is an option. A boiler creates high pressure steam that turns a turbine to produce power. This not likely to become feasible on a manure-based system.