The biogas research is moving along at the UBC Energy Farm. Today, Christoffer Hansen met with Vic and Harley from C.W. Brockley in Vancouver, B.C. to finalize design considerations and begin the construction of the agitation system for each prototype digester. These gentlemen are attempting to create a biogas digester that not only performs the necessary actions required to keep the bacteria happy and making biogas, but one that is able to be replicated using items that are cheap, easy to source, and easy to assemble. The design that they have come up with is unique because small-scale batch digesters do not usually have suitable agitation systems. The result of weak agitation is twofold. First, a hard layer of scum forms on the top of the mixture, disrupting the production of biogas. Second, the methane forming bacteria have a harder time making contact with the tiny bits of organic material that they use to make biogas.

The basic design of the agitator is a shaft that runs the width of the inside of a 55-gallon oil drum, about 6-8 inches from the top. There are pieces of flat bar attached to the shaft in various orientations which will break the scum and the surface of the substrate. Outside the 55 gallon drum the shaft is turned on a bearing by using a hand crank. This will be a safe and effective way to mix drum contents.

Julian Darley visted the farm today and delivered two temperature sensors from California based, Davis Instruments. These temperature probes will give researchers digital data related to the temperature of the digesters.