Farmer's gas project aims to end dirty dairying

Hikurangi farmer Ben Smith is developing technology to turn dairy effluent into biogas energy. Photo / Michael Cunningham

A Hikurangi farmer is hoping the technology his company has developed will turn dairy farm effluent into enough biogas energy to power up to 2000 homes and provide a blueprint for banishing dirty dairying from New Zealand.

Ben Smith, of TS Farming Solutions, is working on technology which would use cellular digesters to generate methane from dairy farm effluent and pump the gas into static turbines, where it would be converted into electrical energy and heat.

The system would also produce sufficient clean water for all day-to-day operational requirements of the integrated farm.

Mr Smith said he hoped to eventually increase his dairy herd from 300 to as many as 3000 and employ up to 80 people.

The first phase of the project - to prove that the system is capable of this increase - should be operational by November this year.

The entire operation, which will cost up to $15 million, should be finished by 2020 when the farm would be able to support the herd increase.

With this increase in output, he said, the operation could export up to 2mw of power - enough to power about 2000 homes.

"This cellular technology is not currently being done in farming but is common practice for metropolitan waste management schemes," he said.

Vegetable waste from Auckland supermarkets, for example, would be used to feed the additional cows, he said, as well as additional cropping which would be contracted out.

Mr Smith said he hoped the patented energy system could be rolled out on to smaller farms, and would create enough energy from one cell for a farm's own milk cooling system to operate.

"We want to get dirty dairying out of New Zealand. This is part of the solution."

He said it not only created energy but could remove up to 60 per cent of greenhouse gases, phosphorus, nitrates and methane produced by dairy farms.

Mr Smith was also developing an integrated fish farm onsite producing eels, whitebait and mullet for domestic and international markets.

The Hikurangi system will be integrated as the cellular digesters help maintain correct water temperatures for the fish and the nutrient rich dry material will be used for fertiliser or fish food.

The company was awaiting approval from the Department of Conservation before it proceeded with the fish farm, as well as legislative changes to strengthen the framework around farming fish within a tank environment.

"This all came about as we wanted to create a viable alternative to mining - we need to create jobs for our people."

Mr Smith said up to 20 Northland agricultural students had connected with the farm through NorthTec, while plans were also being made to introduce international education links.

TS Farming Solutions was one of 10 companies to get funding approval from Callaghan Innovation so far this year, having received about $245,500 through Project and Getting Started grants towards biogas energy research and development.