 crop and its fuel.
Theirs was a real-world study that collected data from jatropha farms and processing plants in Brazil, and included interviews with the farmers and processors. The farms ranged in size from 10 hectares to thousands of hectares.
"This analysis presents a comparison of life-cycle [greenhouse gas] emissions from synthetic paraffinic kerosene (SPK) produced as jet fuel substitute from jatropha curcas feedstock cultivated in Brazil against a reference scenario of conventional jet fuel," the report stated.
Bailis and Baka found that the type of land on which the jatropha plant grew had a direct correlation to its carbon footprint in comparison with petroleum-based jet fuel.
When planted on lands that were already fallow or degraded by use, the jatropha crop reduced greenhouse gas emissions by over 60 percent of the area's baseline levels when compared against production of petroleum-based jet fuel. However, in woodland areas that had been home to trees and shrubs and were cleared for the sole purpose of cultivating and processing jatropha, the emissions ratio actually increased.
Bailis and Baka also found that some farmers struggled due to poor resources.
"A second important finding is that early jatropha projects suffered from a lack of developed seed strains, which led to poor crop yields," the report said.
The results pointing to the importance of careful choice of land and seed may seem obvious. But this is one of the first studies conducted in Latin America that uses hard data and interviews, as opposed to estimates and computer modeling, and applies it to the sustainability criteria developed by the Roundtable on Sustainable Biofuels, according to Boeing.