Cooking with gas from raw sewage

00:00, Oct 18 2012

A system allowing residents to cook a meal using gas from raw sewage is being made and sold in Nelson.

Waste Action has designed the BG5, Bio gas 5000, which stores then converts household waste into bio-energy - believed to be the first of its kind made in New Zealand.

Methane gas produced by domestic waste in the kitchen, garden and from raw sewage was converted into energy which could be used to cook for about two hours a day, help heat a home or run lights, Waste Action co-owner Russell McGuigan said.

"Most septic tanks just hold household waste. These tanks still do that but they also produce bio-energy to offset your energy needs."

While the technology was in use overseas, he was unaware of anyone else making tanks for the system to be used in New Zealand homes. Before working with Richmond Fibreglass he had been forced to look to South Africa to produce the tanks because no-one else was making them.

Richmond Fibreglass owner Errol Harper said the tanks were straightforward to make, once the specifications were finalised and it took five men about five weeks to produce a tank.


"Once we sat down with Russell and looked at the specifications we realised it was achievable, instead of importing them. What we have to do is to make it comparable to a normal septic tank, and we can do that."

The first BG5 had been produced and sold to a home this month while the second sale was under negotiation. The two companies were ready to start making the tanks and taking orders, but costings and a price was still being finalised, Mr Harper said.

The design of the BG5 was created by Waste Action co-owner Bill Rucks and demand for the waste treatment system was predicted to be from residents on lifestyle blocks who were not connected to the town sewerage system and wanted to deal with their waste efficiently.

Waste Action was also working on its next backyard creation, the BG1, a barbecue run off green waste, Mr McGuigan said.

The Nelson Mail