Biofuels

Potential for biomass use ► Total Global Primary Energy Supply (in ExaJoules (10 18 )) EJ EJ EJ ► Actual use of biomass EJ ► Potential of biomass Yearly global photosynthesis ~ 4000 EJ Technical potential raw biomass (2050) 450 EJ Economical potential raw biomass(2050) 150 EJ Economical potential liquid biofuel(2050) 53 EJ

Potential for biofuel production ► Current transport fuels needs: 77 EJ ► Biofuels Ethanol(2004)0.84 EJ 9.5 Mha Bio diesel(2003)0.06 EJ 0.5 Mha ► 856 Mha would be required to meet current fuel needs

Land suitable for agricultural production ► 856 Mha would be required to meet current fuel needs ► Land suitable for agriculture * Total used Mha Industrialised countries Mha Developing countries Mha Total suitable4188 Mha Industrialised countries 1406 Mha Developing countries 2782 Mha * excludes protected areas and closed forests and is crop specific, the total land suitable for agriculture is not necessarily suitable for biofuel crops.

Most important bio-fuel crops Crop: Main producing countries: Land under irrigation (estimates): Sugar cane Brazil / India / China / Thailand 14% / 80% / 28% / 64% Sugar beet France / USA / Germany / Russia 15% / 53% / 5% / 5% Cassava Nigeria / Brazil / Thailand / Indonesia 0% Maize USA / China / Brazil / Mexico 21% / 40% / 0% / 17% Oil Palm Malaysia / Indonesia / Nigeria / Thailand 0% Rapeseed China / Canada / India / Germany 3% / 0% / 8% / 0% Soybean USA / Brazil / Argentina / China 10% / 0% / 0% / 29%

► Rainfed agriculture:  Pressure on land resources ► Irrigated agriculture:  Pressure on water resources Impacts of biofuels

What is the potential of the natural land resources base ? Sugar cane Sugar beet

What is the potential of the natural land resources base ? Cassava Maize

What is the potential of the natural land resources base ? Rapeseed Soybean Oilpalm

Crop: Fuel product[1][1] Annual obtainable yield (l/ha) Energy yield (GJ/ha) [2] Evapo- transpiration equivalent (litre / litre fuel) Potential crop evapotranspira tion in mm/ha (indicative) Irrigated or Rainfed Rainfed conditions Water Resource Implications under irrigated conditions Actual rainfed crop evapotranspiration in mm/ha (indicative) Irrigation water required (mm/ha)[3][3] Irrigation water required in litre / litre fuel Sugar cane Ethanol (from sugar) Irrigated / Rainfed Sugar beet Ethanol (from sugar) Irrigated / Rainfed Cassava Ethanol (from starch) Rainfed Maize Ethanol (from starch) Irrigated / Rainfed Oil palmBio-diesel Rainfed Rape- seed / MustardBio-diesel Rainfed SoybeanBio-diesel Rainfed [1][1] Energy density: Bio-diesel 35 MJ/l Ethanol 20 MJ/l [2][2] FAO (2006b). Starch market adds value to cassava, on-line available at: Global Petroleum Club, Energy Content of Biofuel, on-line available at: Marris, E. (2006). Drink the best and drive the rest. Nature, 444, 670–672, 7 December. USDA (2006). The Economic Feasibility of Ethanol Production from Sugar in the United States, on-line available at: [3][3] On the assumption of 50% irrigation efficiency

A few numbers ► Water needed to produce:  1 kilo of wheat: litres  1 kilo of meat (beef): litres ► Daily water requirements per person:  Drinking: 2-3 litres  Domestic needs: 20–300 litres  Food: litres ► with litres of water, we can produce:  food for one person for one day  1 litre of biofuel

What is the potential of the natural water resources base ?

What is the potential of the natural water resource base ?

Biofuel and water use (2005) Source: de Fraiture, IWMI, 2007

Projections for water demand Source: de Fraiture, IWMI, 2007

NAS report on water and biofuels in the United States (2007): ► Currently, biofuels are a marginal additional stress on water supplies at the regional to local scale. However, significant acceleration of biofuels production could cause much greater water quantity problems depending on where the crops are grown. Growing biofuel crops in areas requiring additional irrigation water from already depleted aquifers is a major concern. ► The growth of biofuels in the United States has probably already affected water quality because of the large amount of N and P required to produce corn. If projected future increases in the use of corn for ethanol production do occur, the increase in harm to water quality could be considerable.

Conclusions ► World water system already under heavy stress due to agriculture and other uses ► Agriculture main water user (70%) ► Future water demand for agriculture in the rise ► Climate change likely to result in increased demand for irrigated water ► Bioenergy likely to add to pressure on water:  depending on type of crop  depending on farming system: rainfed/irrigated  depending on region ► China, India, already facing serious water constraints ► Keep an eye on sugarcane