163 Cleveland Terrace, Maitai , Nelson 7010 , New Zealand
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Biogas at Home

Biogas Digester

Commissioning a biodigester takes a bit of time and effort utilising 100 ltrs of fresh cow manure to get the digester started. You can also use fresh sheep, goat or Alpaca manure, and other manures like horse manure can also be used but will need added probiotic powder (available extra) to activate the digester.  Chicken manure is not recommended due to acidic nature.

Once gas is produced after 4 to 6 weeks (depending on temperature and how fresh the manure was) then you can start adding food waste - but hold off on acidic foods like citrus peels until the digester is at peak performance.
Frenergy IBC Biogas Digester

Biogas Bags

The 500/600 litre gas bags supplied (when full) over an hour of cooking time and the more you feed the digester with food waste, or more manure, the more gas it will produce for your cooking needs.

Our family of 3 adults (including granddad) and two children produce about 3, buckets of food waste a week which provides all the gas we need for cooking for the whole family. When adding food waste to the digester, add the same volume with fresh water and chop or macerate the contents as much as possible to speed up gas production - the anaerobic bacteria prefer small particles to eat rather than large... Methane is their by-product, which provides us with a cyclic process where 'waste' is converted to energy - and in Nature there is no such thing as waste, so we are emulating Nature.
500/600 litre Biogas Bags, Puxin

Biogas Accessories

Besides Methane other gasses are produced too like CO2 and H2S (Hydrogen sulphide) which stinks like rotten eggs but our filter systems remove this smelly gas before it reaches your cooker. Methane (CH4) does not smell at all and is not dangerous because none of the gas is under pressure and as soon as it is mixed with air it becomes completely non-volatile.

The stove takes oxygen from the air at the flame, not before it like LPG does. We use a small gas pump of 20W, plugged into a 230V power outlet near your stove. If you don't have 230V power then you can use sand bags or other weight placed on the gas bag to push the gas through the gas line.