Direct and indirect land-use competition issues for energy crops and their sustainable production - an overview

Biofuel production from energy crops is land-use intensive. Land-use change (LUC) associated with bioenergy cropping impacts on the greenhouse gas (GHG) balance, both directly and indirectly. Land-use conversion can also impact on biodiversity. The current state of quantifying GHG emissions relating to direct and indirect land-use change (iLUC) from biomass produced for liquid biofuels or bioenergy is reviewed. Several options for reducing iLUC are discussed, and recommendations made for considering LUC in bioenergy and biofuel policies. Land used for energy cropping is subject to competing demands for conventional agriculture and forest production, as well as for nature protection and conservation. Biomass to be used for bioenergy and biofuels should therefore be produced primarily from excess farm and forest residues or from land not required for food and fiber production. The overall efficiency of biomass production, conversion, and use should be increased where possible in order to further reduce land competition and the related direct and iLUC risks. This review of several varying approaches to iLUC substantiates that, in principle, GHG emissions can be quantified and reductions implemented by appropriate policies. Such approaches can (and should) be refined and substantiated using better data on direct LUC trends from global monitoring, and be further improved by adding more accurate estimates of future trade patterns where appropriate. This brief discussion of current policies and options to reduce iLUC has identified a variety of approaches and options so that a quantified iLUC factor could be translated into practical regulations - both mandatory and voluntary - with few restrictions. Depending on the future development of energy cropping systems and yield improvements, sustainable bioenergy production could make a significant contribution to the future global energy demand. (C) 2010 Society of Chemical Industry and John Wiley & Sons, Ltd