Gwendolin Münch, Jennifer Eiring, Aileen Jahr
Every household produces waste. Particularly the organic waste has great and rarely used potential. Rather than paying for its collection, one could use it to supply one's household with methane gas, e.g. for cooking. Our goal is to build a biogas plant that is simple, low-cost and as efficient as possible. Any household should be able to afford it and any household should be able to use it. We want to maximize the quantity of the methane output as well as the speed of its production. Therefore, we used heating of the organic material, special strains of fungi that speed up the decomposition, as well as a stirring system. After the methane production, the remaining biomass can be dried for use as fertilizer in the garden. Thus, the efficiency is high and the initial investment is low. The necessary resource needed to run the biogas plant is everyday organic waste such as garden waste, excrements (ideally from herbivores) and compost. The realization requires neither special skills nor a full wallet. The cheapest and simplest method requires only a few containers, hoses and organic waste, however, larger quantities of cleaner biogas can be produced with little additional investment based on the same principle: Biogas forms as the organic waste is fermented in an airtight bucket. The biogas can then be cleaned and collected using a water bath, steel wool and a compressor. Addition of certain strains of fungus, heat and mixing speed up the decay of cellulose and improve the yield. Using hoses, the gas is then guided through a water tank and through steel wool before being stored in a gas cylinder using a compressor. The individual steps of this process worked almost without problems and as expected, however, frequent modifications and a shortage of time have not allowed us to combine all components into a single system, yet. This will be the next step. In addition, a pressure sensor that automatically turns the compressor off when a certain pressure is reached would be beneficial to prevent the pressure in the system from getting too large. We are confident that we will be able to demonstrate such a finished and working system before the competition.
