A number of solutions to the sustainable aviation problem have been advocated in the past. Broadly speaking, these solutions fit into three categories: kerosene equivalents, batteries and hydrogen. Biofuels and synthetic kerosene, although a potential temporary solution to the aviation industry’s carbon emissions, are not sustainable in the long-term. The impact on air quality as a result of NOx emissions by combusting kerosene or kerosene equivalents is up to 4.4 times higher than the impact of CO2 emissions on the environment.

Batteries are not suited for aviation on their own due to their weight. However, battery and hydrogen technologies are closely linked since both make use of the same electric engines. Hydrogen in gaseous and liquid state as well as contained in carrier fluids is seen by many to be the long-term solution. A single wind turbine would be able to provide the power for a commercial aircraft. Fuel cell technology has the potential to change not only aviation but transportation in general, leading to a sustainable, future hydrogen economy.

Although our aircraft are small, our ambition is not. For example, we are working internationally to develop certification guidelines for hydrogen propulsion. We firmly believe that our work can be used to have the first hydrogen-powered passenger aircraft such as the Greenliner, shown above, flying by 2030, potentially by a spin-off start-up.