Biofuels: indirect land use change and climate impact

Jun 2010

Biofuels displace fossil fuels, mainly oil, in the transport sector. Although biofuels have roughly the same tailpipe carbon emissions as fossil fuels, this carbon was previously absorbed from the atmosphere when the biofuel feedstock was grown. Net carbon emissions do occur, though, because biofuels production and feedstock cultivation require inputs in terms of fertilizer application, use of diesel for agricultural machinery, energy in processing the feedstock to fuels, etc. The use and/or production of these inputs generate greenhouse gas emissions, too.
It was largely this thinking that was reflected in the sustainability criteria for biofuels that were put in place in the renewable energy directive (RED). The RED requires that the whole production chain from cultivation of the feedstock up to use of the biofuels is considered, including direct conversion of land to grow biofuels feedstock.
However, the RED does not take into account the potential indirect effects of biofuels production. When biofuels are grown on existing arable land, indirect land use change (ILUC) will ensue, since current demand for food and animal feed will push these production activities into new areas such as forests or grasslands. Conversion of forest or grassland to agricultural land can lead to very significant releases of carbon to the atmosphere. Studies show that emissions resulting from ILUC are so significant that they could sway the climate effects of biofuels from positive to negative, compared with fossil fuels. As yet, however, the most recent range of studies have not been systematically compared and summarized.
The objective of this study is to:
- Compile the available recent literature on ILUC emissions;
- Compare these emissions with the assumed gains of biofuels;
- Assess how ILUC changes the carbon balance of using biofuels;
- Formulate policies to avoid these extra emissions associated with ILUC.
All the studies on global agricultural markets reviewed predict that new arable land will be required to meet future global demand for food and feed. Although there will be increased productivity on current arable land (intensification), food and feed demand will probably grow faster, which means that mobilization of new land is likely to occur. Biofuels produced from crops (the current mainstream practice) will add extra demand for crops like wheat, rice, maize, rapeseed and palm oil. This will increase prices for these crops (as well as for land) and lead to two impacts: intensification of agricultural production and conversion of forests and grasslands to arable land.
To conclude, by properly accounting for the emissions associated with indirect land use change a real reduction of 70 Mt CO2-eq per year seems possible.

By: H.J. Croezen G.C. Bergsma M.B.J. Otten M.P.J. van Valkengoed (CE Delft)

 
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