Carbon footprint tick for canola

WA farmers are cleaner and greener than first thought, after a groundbreaking study found the carbon footprint of biodiesel produced from canola is far smaller than expected.

As part of a five-year project on crop growth emissions, researchers from the Department of Agriculture and Food (DAFWA), the University of WA (UWA) and Curtin University used lifecycle analysis to determine the emissions generated by biodiesel production all the way from sowing canola through to burning the end product.

The results are nothing short of exciting and in the future could present WA farmers with the opportunity to cash in on the biodiesel market.

As DAFWA researcher Dan Carter explains, the project began with an invitation of the former Australian Greenhouse Office, now the Department of Climate Change and Energy Efficiency, to establish base line emissions from wheat, lupins and canola through field experiments.

“In the first instance we looked at nitrous oxide, methane and carbon dioxide being emitted from the production of canola, lupins and wheat, ” Dr Carter said.

“Once we knew what the paddock was doing, we were able to put that into a lifecycle assessment that looks at the production of all the pesticides and fertilisers right through to the on farm emissions and also the post farm emissions.

“We found that because we’re very efficient in using our nitrogen fertilisers in WA, modelling done overseas overestimated the carbon dioxide equivalents that we produced here.”

In fact, the study, using lifecycle analysis, found that emissions from the biodiesel production and burning were 41 per cent less than the default emission values currently recommended by the Intergovernmental Panel for Climate Change (IPCC).

Previous claims had alleged about one per cent of nitrogen fertiliser became nitrous oxide emissions, a greenhouse gas almost 130 times more powerful than carbon dioxide, during plant growth.

But the WA team, which included Louise Barton from UWA and Wahidul Biswas from Curtin, found the level was just 100th of that figure.

“The end result of the five years of field experiments has changed the Australian nitrous oxide emissions standards being used from one per cent of nitrogen fertiliser used to 0.1 per cent for Australian grower, ” Associate Professor Barton said.

The findings shoot down conclusions from a previous Brazilian study, which found the replacement of petroleum diesel by biodiesel would do little to decrease total greenhouse emissions.

Significantly, the WA study used emission values calculated at the Cunderdin Agricultural College and is a boon for WA growers in a market becoming increasingly conscious of its green credentials.

“Conclusions not only support the viability of canola for biodiesel production in WA, but also highlights the efficiency of the State’s canola growers in minimising greenhouse gas emissions, ” Dr Carter said.

“The data shows there is a positive outcome using the biodiesel.

“It’s showing that Australia is probably well ahead of places like Europe and South America in their ability to control emissions from agriculture.”

Research is now centring on whether different sources of nitrogen, other than urea, could be used in farming to further cut emissions.