Eurocopter and parent company EADS have teamed with Argentina-based BioCombustibles del Chubut (BC) to study the feasibility of building an aviation biofuel factory in Brazil. The three companies signed an agreement in June. The biofuel, made from algae, could be used in Eurocopter’s diesel engines for light helicopters, which are now in the research stage (see AIN, February, page 44).

While Boeing has touted jatropha–a vegetable that grows in arid soils–as a potential source for biofuels, EADS is betting on algae. It can grow in salted, not-so-clean water and needs only one-twentieth of the surface jatropha would need to produce the same amount of fuel. Moreover, algae culture is CO2 intensive. According to EADS chief technology officer Jean Botti, one pound of algae absorbs 1.7 pounds of CO2. In fact, it absorbs so much CO2 that a production facility would need to be located next to a plant that emits a lot of CO2 and located near an airport. The CO2 would be captured and fed to the algae.

EADS’s and Eurocopter’s goal is to devise a “drop-in” biofuel solution that aircraft could burn with no modifications. EADS has been flight-testing a demonstrator–a Diamond Aircraft DA42 New Generation powered by two Austro Engine AE300 diesel engines, fed with algae fuel. “The only modification we had to do was to turn down the injection nozzle a little, because biofuel is more efficient than conventional jet-A1 and otherwise the combustion chamber would overheat,” an EADS spokesman told AIN.

EADS and Eurocopter are not divulging a timetable for developing algae-based biofuel and are focusing on  technology for mass production, which they hope will reduce the cost. “The biggest challenge is to set up a decentralized network of algae producers and refineries that can operate without subsidies,” the spokesman explained.

While an algae-based biofuel is greener than conventional petroleum-based fuel because algae absorb CO2, it is not carbon neutral. In Germany, the Bavarian aerospace research and technology program is funding work–the “Bay68” project–to determine the CO2 emissions at every step of the process chain. “In particular, one needs to look at the harvesting and drying of the algae biomass, the oil extraction process [several methods], the refining of the oil into fuel [which needs hydrogen] and all logistics and transportation needs,” the spokesman said.
Algae-based fuel also reduces other emissions compared with traditional jet-A.
According to EADS, tests indicate that exhaust gas contains eight times fewer unburned hydrocarbons. Nitrogen oxide (NOx) and sulfur oxide emissions will also be reduced, by as much as 40 percent and 98 percent, respectively, as a result of the biofuel’s low nitrogen and sulfur content.

Eurocopter and its partners in Europe’s Clean Sky research project are about to launch a call for proposal on diesel engines for helicopters. The first call for proposal, issued last year, failed. This time, the project will require a greater reduction in weight, and the budget accordingly will be larger.