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Install a biogas digester (only if viable)

If step 7 said go, install a proven prefabricated or engineered digester. Biogas is flammable and contains toxic hydrogen sulphide, so the gas side must be done properly.

How

1. Buy a complete system from a recognised manufacturer or follow a design from an established programme rather than improvising.
2. Site it in full sun where possible, away from buildings, on firm ground, with the pressure relief valve outdoors and ignition sources kept away (Ontario guidance: at least 3 m from the relief valve).
3. Fence the digester and the digestate tank so children and animals cannot walk on or fall in.
4. Run gas pipe with a water trap at the low point and a filter for hydrogen sulphide (one manufacturer uses iron wool, replaced every 2 to 4 weeks).
5. Connect only biogas-rated appliances; never connect to an LPG or natural gas system.
6. Leak test every joint with soapy water before first use.

Safety: Methane is explosive at 5 to 15% in air. Hydrogen sulphide is heavier than air and can kill quickly at high concentrations. Never enter a digester, pit or tank, and design it so no one ever needs to.

Sources

1. Anaerobic Digesters and Biogas Safety. Farm Energy, Extension Foundation (eXtension), accessed 2026-11
2. Hydrogen sulphide in agricultural biogas systems. Government of Ontario, Ministry of Agriculture, Food and Agribusiness, accessed 2026-11
3. Biodigester user manual (B2C, 2021). Sistema.bio (manufacturer), accessed 2026-11
4. Micro-Scale Biogas Production: A Beginner's Guide. National Center for Appropriate Technology (NCAT) ATTRA, accessed 2026-11

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