For example, evapotranspiration water requirements in the U.S. necessitate 500−4000 L of water to grow enough feedstock to produce 1 L of ethanol (Lw/Le) (Figure 1); processing water requirements for a typical sugar cane or corn ethanol refinery are only 2−10 Lw/Le (17). Nevertheless, the water used in biofuel processing and other stages in biofuel production is often withdrawn from local point sources and can have localized impacts on water quality and quantity.

A new study done by the University of Twente in the Netherlands has found that sugar beets take 1,400 liters of water to make 1 liter of biofuel and it is the most efficient. Next generation biofuels made from algae or other processes were not included and make be efficient in terms of water usage. Other sources: Alpha Galileo.

An example is biodiesel, which is made from rapeseed, soya or jatropha. On average, it takes 14,000 litres of water to produce one litre of biodiesel from rapeseed or soya. However, the water footprint for rapeseed in Western Europe is significantly smaller than in Asia. For soya, India has a large water footprint, while the figures for countries such as Italy and Paraguay are more favourable. Jatropha, which is increasingly used for biomass production, has an even less favourable water footprint of 20,000 litres of water on average for one litre of biodiesel.