Use of inadequate data and methodological errors lead to an overestimation of the water footprint of Jatropha curcas

Abstract

In their recent article, Gerbens-Leenes et al. (1) calculated the water footprint (WF), the amount of water required to produce 1 GJ of energy, of several bioenergy crops. The water footprint of Jatropha curcas was remarkably high (8.6 times higher than the WF of sugar beet, the most water-efficient crop), which may have serious implications for its future management. However, we strongly believe that jatropha's WF was dramatically overestimated because of inappropriate use of data and methodological errors. For their calculations of jatropha's WF, the authors relied on a nonpeer-reviewed report (2), providing data of the total available water in plantations, summing rainfall and irrigation, but not of evapotranspiration, required to calculate …