sentences:  It takes approximately 10% of methyl alcohol by weight of the fatty substance to start the transesterification process.Estimates of "Jatropha" seed yield vary widely, due to a lack of research data, the genetic diversity of the crop, the range of environments in which it is grown, and "Jatropha"s perennial life cycle.Seed yields under cultivation can range from 1,500 to 2,000 kilograms per hectare, corresponding to extractable oil yields of 540 to 680 litres per hectare (58 to 73 gallons per acre).