A biogas recovery system using methane from dairy effluent to generate electricity and heat water was one of three finalists in the Energy Technology of the Year award in the 2017 Deloitte Energy Excellence Awards.
“Staging various aspects is easier on your budget, especially in tough times, and doing the right thing at the right time ensures compliance,” Geoff Irwin says.
Irwin called in Hi-Tech Enviro Solutions in 2012 to solve a storage issue on his 270 cow farm.
“I didn’t have enough storage and wanted to resolve this before it became a compliance issue. I also wanted to limit the amount of rainwater entering the system and wanted to add a stone-trap which, with the additional storage, would make the overall system more flexible.
“At the time I was just wanting to store effluent from the dairy shed but I was planning to grow the herd to about 320 cows and build a couple of herd homes, so I wanted a system which would future-proof the farm.
“The result was a 2000m3 lined pond for the effluent from the dairy, and allowing pond water to be used to dilute the effluent from the herd homes (built in 2016) before it was pumped onto pasture.
“The pond has a five-drum pontoon with floating pipe system which connects the pontoon to the shore, limiting access onto the pontoon and allowing me to move it around the pond for optimum pumping and agitation.
“The new storage system worked well but getting effluent out onto pasture was still a manual job which involved dragging lines from paddock to paddock.
“I also had an issue getting effluent to the back of the farm so in 2016 Hi-Tech designed and installed a 1.6km hydrant line which enabled fertiliser to be easily and quickly spread across the entire farm. Trenching in the permanent hydrant line was a huge saving in time and labour.”
Irwin’s effluent system includes the five-drum pontoon with floating delivery, a vertical stirrer, 11kW Doda pump and a Cobra travelling rain gun.
“The Cobra achieves low application depths and rates but also spreads over large distances. It doesn’t have long boom arms so it’s easy to move around and set up.
“The entire system is cost effective, easy to manage and works well for us. Having a lined storage pond gives storage for when conditions aren’t suitable for applying effluent to pasture, and allows us to have more control and apply the effluent at the optimum time to maximise pasture growth and nutrient utilisation.”