Alternative airline fuels considered

BERLIN — Some of the world's biggest aviation companies are turning to alternative fuels — made from sources as diverse as hydrogen cells or algae — as soaring oil prices drive the search to build and fly more fuel-efficient planes.

Boeing and its European rival Airbus showed off their latest alternative-fuel projects Tuesday at the Berlin Air Show, held against the backdrop of oil prices that hit $135 a barrel last week.

Boeing displayed a one-seater demonstration airplane that can fly on batteries and hydrogen fuel cells. While the plane is still in the early stages, the company said that test flights have shown "a manned airplane can maintain a straight-level flight with fuel cells as the only power source."

Boeing said the technology could potentially power small manned and unmanned aircraft. But it said it "does not envision fuel cells will provide primary power for large passenger airplanes," although it will continue investigating their potential.

Airbus brought along a demonstrator version of its A320 passenger jet that uses fuel cells to power some of the aircraft's steering systems. The company said it sees great potential in fuel-cell applications.

Dutch airline KLM, meanwhile, said at the show that it had signed a contract with AlgaeLink for fuel made from algae for a pilot project whose first test flight is scheduled for this fall.

AlgaeLink plans to set up a pair of plants this year — in the Netherlands and Spain — and said its algae-based kerosene will be mixed with conventional fuel. But KLM's goal is to fuel its entire fleet with kerosene from algae and other plant-based oils.