Research confirms grass is greener
by Mike Isle
New research by Lincoln University shows grass is indeed greener, at least when it comes to dairy farm energy use and hectare and milk production output.
Lincoln University PhD researcher Hafiz M Abrar Ilyas looked at the energy consumption of Canterbury dairy farms using direct (fuel, electricity, labour) and indirect (fertiliser, imported feed supplements, machinery) energy inputs.
He examined a pasture-based dairy system and a hybrid barn system that featured both pasture and barn.
Hafiz found the energy footprint in pastoral systems for each hectare consumed 9.5% less energy than the barn-based.
He said electricity consumption was higher due to the use of more electrical equipment in barn facilities, as was the use of petrol and diesel, with machinery involved in feed production and distribution.
More labour was also required.
On a milk production basis, pastoral systems consumed six per cent less energy for each kilogram milk solids.
However, the barn system did use 39% less fertiliser energy but had 80% higher feed supplement energy use.
Hafiz said the research suggests that energy consumption in pastoral systems in terms of both hectare and milk production output is more efficient. “To increase sustainability consideration needed to be given to better electricity use, more efficient irrigation systems and milking sheds.
Energy auditing and the use of more renewable energy sources were recommended.
“Reducing the number of tractor passes, less energy-intensive feed supplements and lower fertiliser consumption would also reduce energy usage in New Zealand dairy systems.”
Hafiz acknowledged help from Majeed Safa (supervisor), Professor Alison Bailey (supervisor), Marvin Pangborn, Sara Rauf, Mat Cullen, and Helen Thoday.