Airbus tests frugal fuel cell

Airbus has completed the latest stage in its civil aerospace fuel-cell programme by harnessing the by-products of water and heat for use within existing flight systems.

Claus Hoffjan, manager of Fuel Cell Development at Airbus, has been heading the research and development of a system which can generate up to 20KW of electrical power. The system, first flight tested in February 2008 to provide energy for backup hydraulic and electric power systems on an A320, works in a similar way to conventional fuel cells by combining hydrogen with oxygen in a cold- combustion process.

The innovation uses a separate condenser to collect the water generated as a result of the chemical reaction between hydrogen and oxygen. A further by-product, hot air, is collected in a humidifier and harnessed to heat the interior of the cabin. The process removes the need for an additional auxiliary power unit (APU), a fuel-tank inerting system, a ram air turbine or a water-storage system, which can claim up to 2.2 tonnes of weight on a typical A380.

Hoffjan said this approach will result in significant weight reductions and improve overall energy consumption: 'In an aircraft, you have a separate system for everything... but we can combine this into one system using the same amount of energy,' he said.

Over the past few years, companies such as Airbus and Boeing have increased their research activity in fuel-cell systems. While their application for commercial aircraft propulsion is currently unfeasible due to their low energy output, their use as auxiliary power units (APUs) could help the aviation industry reduce its CO₂ and NOx emissions.

Most research activity has centred around the use of fuel cells to power internal systems such as lights, air conditioning and cabin pressure. However, Airbus claims that it is the only company with an advanced model of a fuel cell able to integrate systems in this way.

To mark the development of the technology, Hoffjan and his team entered the EADS Hall of Fame in Bordeaux earlier this month after being presented with the 'Great Inventors' award for their work.

'The next step is to bring this into an aircraft and we plan to begin flight tests in 2012', said Hoffjan. 'However, this is something we can also use in the automotive industry, which relies heavily on high-energy engines running on petrol. In the future, we won't have enough oil to meet demand so we need to use something else and I believe if we find a good way of sourcing hydrogen, this will be the way forward.'

As well as sourcing hydrogen, Hoffjan believes a further obstacle to the use of fuel cells is availability and high cost. Currently, most fuel cells are assembled by hand, however, Airbus said that it plans to use an automated process that could bring the price down enough to undertake wide-scale production.

Ellie Zolfagharifard