Venture Southland aims to facilitate and streamline the process of methane recovery on dairy farms, aiming to develop a general specification to standardise methane recovery for a range of dairy farms.

Venture Southland identified the potential for methane recovery in the Regional Energy Strategy, outlining that using methane as an energy source on dairy farms would have the potential to significantly reduce electricity use and costs whilst also having significant environmental benefits.

In 2012 Venture Southland invited NIWA to present on the topic of methane recovery on dairy farms at the Regional Energy Conference and Workshop. The event was well attended by farmers from throughout the region, many of whom were interested in potentially developing a methane system for their own farms.

Later in 2012 a methane monitoring programme was established on a Dacre dairy farm by NIWA. The monitoring ended in September 2014, demonstrating that the amount of methane produced during the trial was much larger than what previous national models had forecast, had 80% purity, and was suitable to support a methane to energy project.

From this foundation work, planning commenced in 2015 to build and commission a fully integrated methane to electricity plant at Isla Bank. Following a successful pilot period the Dairy Farm Methane Recovery Project was officially launched to the public in April 2017. The project showed that methane recovery helps to significantly reduce costs, harmful greenhouse gases and odor on farm. It also identified that the waste to energy conversion project helped to produce NPK (nitrogen, phosphorus, and potassium) for fertiliser.

This project was a collective effort by the EECA, the National Institute of Water and Atmospheric Research (NIWA), agricultural engineers Dairy Green, Venture Southland and the Fortuna Group which contributed significant resource and the site where the system is now operational.

Glenarlea Farm

The Glenarlea Farm, a Fortuna Group dairy farm under the stewardship of David Dodunski, was the farm that piloted the methane to electricity project. As a result of this the farm now converts methane gas captured from the dairy effluent pond into electricity for the dairy shed. The electricity generated is also used to heat water for wash-down purposes on the farm.

The official opening of the Glenarlea Farm Methane recovery system in April 2017 marked a significant step towards a cleaner more cost effective dairy sector not only in Southland but throughout New Zealand.

The recovered methane system at Glenarlea Farm fuels a generator that produces 30kW of energy. It will remain operating at this rate until the vast amount of hot water created is able to be effectively utilised in meeting the farm’s energy needs, including powering an electric farm bike. The farm has sufficient gas for the system to operate for up to 17 hours per day.

The Energy Efficiency and Conservation Authority (EECA) and Venture Southland continue to monitor the project and analyse the economic payback of the investment.

The technology has also been trialled in dairy farms in the Waikato and Geraldine and a pig farm in Taranaki, but the Glenarlea Farms project is the southernmost application, demonstrating the technology operates in southern conditions.

The costs of implementing a methane recovery system will vary depending on the effluent pond systems used. However, through the savings farmers will gain from being able to generate electricity themselves, the recovery system will eventually pay for itself.

A Facebook video-clip produced as part of ‘The Country Series’ by ASB Bank focusing on Glenarlea Farm attracted 122,000 views in four days.