By Renewable Energy Focus staff
In an article in Global Change Biology Bioenergy, researchers assess the net greenhouse gas savings of bioethanol from sugarcane as compared to the use of fossil fuels.
They found that land use change, fertilisation, residue burning, and tillage had the largest impact on greenhouse gas emissions.
Dr Klaus Butterbach-Bahl, Head of the Department of Atmosphere/Biosphere Interaction and Global Change at the Karlsruhe Institute of Technology, says: “It is also very likely that N2O emissions from sugarcane production systems have been seriously underestimated so far when using standard IPCC methodology.
“The diversity of sugarcane production systems and the remaining uncertainties with regard to the GHG balance of bioethanol from sugarcane clearly show that more measurements are needed for a full environmental assessment.”
Dr Cardoso Lisboa and co-authors suggest changes at all stages of the sugarcane production in order to maximise greenhouse gas savings.
For example, simultaneous provision of irrigation water and fertiliser would allow the reduction of fertiliser rates in sugarcane production systems. Furthermore, the conversion from pre-harvest burning to no- or minimum-tillage systems with mechanised harvest may better maintain or even increase soil C and N stocks, they found.