A small plane powered by hydrogen fuel cells, has successfully completed three short flights above Spain, providing ‘promises for a greener future’, according to Boeing, the company behind the craft.

Three test flights of the two-seater aircraft took place in February and March at an airfield at Ocana, south of Madrid. The plane was modified to include a hybrid battery and fuel cell system developed by UK firm Intelligent Energy.

The electric motor coupled to a propeller, was powered by the fuel cells. These create electricity by combining oxygen and hydrogen, but produce only heat and water as exhaust products.

During take-off the planes batteries were used to provide an additional boost, but whilst in the air, the plane relied entirely on the cells.

Although the test were successful, Boeing said that it did not believe the fuel cells, which have a flying time of 45 minutes, could be the primary power source for large passenger aircraft, however, it said that it is possible that the fuel cells could be used as a secondary source of energy for large planes.