Home Biogas Systems

Posted on 10 March 2013

Biogas is a type of biofuel that is formed when organic material decomposes in the absence of oxygen - such as undeground in a landfill, deep underwater, or naturally in the guts of animals and humans. When manufactured, the most abundent component of biogas is methane, which also happens to be a major part of natural gas and as such can be used as a fuel for cooking, heating or transport.

Production of biogas involves the process of anaerobic digestion (or fermentation) of biological materials. In an eco home environment, biogas can be produced from kitchen food waste - or from plant and animal waste if you have access to a farm or lifestyle block.

To construct your own home biogas system you'll need a digester tank, an inlet, a gas holder tank, and outlets for the biogas and waste products. As there are other gases combined with the methane in home based biogas, it would be hardly worthwhile to use just a single stanard 200 litre drum for biogas production - the amount of methane produced would only be about enough to run a stove-top gas burner for about 15-20 minutes per day. Realistically at least three drums would be required in order to produce enough gas for cooking.

To produce biogas, mix water with biomass and then keep it airtight for around a week at a temperature that resembles the guts of an animal. At that point in time your biogas generator will start producing usable gas and you should continue to feed it more organic material and water as required.

In many developing countries biogas is already commonly used as a low cost fuel for heating and cooking. Recently there was a PledgeMe project that aimed to transform a Samoan village with Biogas. With a target of just $36,000 it would have been possible to supply six households with full biodigester systems, biogas cooktops and biogas lights. Unfortunately the initial fundraising round was unsuccessful but recently a new fundraising plan was submitted which will allow work to proceed once just $4500 has been raised.