“However, we have very little empirical data on the impact of stubble removal on carbon levels in the soil, and this is definitely an area which requires further research to provide better assessments.”
Additional sustainability issues arise where the feedstock needs to be transported long distances. Transport increases the greenhouse gas emissions of the feedstock substantially. The use of waste wood diverted from landfill is one such feedstock where this issue is pronounced, particularly in regional areas where numerous residue sources are used to provide the amount of feedstock necessary for a viable industry.
International sustainability credentials
Although no scheme of sustainability credentials has yet been achieved in Australia, there are several being developed overseas, such as the Roundtable of Sustainable Biofuels (RSB) initiated by the École Polytechnique Fédérale de Lausanne. There are numerous other schemes, directives and policies in place overseas which aim to address sustainability issues. However, the RSB scheme is one of the first to recognise that sustainability criteria may reduce the impact of the activities directly associated with the biofuel industry, but that indirect impacts, such as changes in land use or food versus fuel, are the domain of the government itself and not a sustainability criterion.
According to CSIRO’s Dr Andrew Braid, also from the Sustainable Biomass Production project: “Direct impacts are usually divided into environmental, social and economic, however, there are crossovers between these divisions. It is the indirect impacts, like the effect on food security or changes in land use, which are making the headlines. Addressing the direct impacts on the environment and community is just as important.”
An Australian sustainability standard?
Australia does not currently have a sustainability standard, although New South Wales has used the developing RSB standard in its legislation. Developing a national standard will be important for industry and governments.
“A well-founded national standard, which is internationally recognised, will help the industry to demonstrate its sustainability credentials to Australian consumers, as well as to access certain markets such as the European one which legislates a minimum standard,” says Dr Braid.
“In addition, it will help to prevent Australia becoming the dumping ground for fuel or biomass produced in other countries that does not meet those international sustainability standards.”
How much biomass is out there?
Assessment of biomass potential in Australia is complicated by varying definitions not only of how to scientifically assess the theoretical potential of biomass, but also the meaning and calculations for the real potential. The key is to integrate what is physically achievable with the environmental and economic potential, and what is able to be implemented with current policy and infrastructure settings.