It has been a week since the initiation of the probiotic fertilizer and the batch-style biogas system at the Local Energy Farm Demonstration Project located at UBC. At present, certain aspects of daily farm upkeep rely on the work of dedicated volunteers. I considered this in the creation of the biogas digesters and attempted to make a system that was as easy to maintain as possible for the volunteer workforce.

At minimum, the biogas digesters need to be agitated once a day. In my perfect world, agitation would occur three times—once in the morning and twice during the heat of the day. Remember, agitation breaks up the hard layer of scum that tends to form on the surface of plant based substrates and it mixes the plant matter in order to allow bacteria to come into contact with new material to digest. Agitation should take about thirty seconds for each digester. A volunteer cycles the handle clockwise for about 5-10 revolutions and then counter clockwise for another 5-10 cranks. Simple!-Finished and on to the next farm task!

The probiotic fertilizer needs less frequent agitation (once a week instead of daily). The “airtight” lid is taken off the brew, a wooden oar is inserted into the mix, and the contents are mixed and churned for a minute or two. Usually this makes a lot of foam as carbon dioxide is released from the mixture. After mixing the lid is re-secured and awaits the next week.

As you consider the infrastructure and process you are going to develop on your farm try to make it use as less energy as possible for up keep and maintenance. To invest a little extra thought and energy in the planning and design phase can allow you to have multiple initiatives underway, which, once started, can continue without a lot of extra physical input.