Engineers from the Technion-Israel Institute of Technology had devised and patented a safe and inexpensive technique for generating hydrogen from water and aluminum particles on-demand while in-flight.

The resulting hydrogen can then be converted into electricity, thereby reducing the reliance of aircraft on fossil fuels and paving the way for substantially less polluting air travel.

“Hydrogen produced onboard the aircraft during flight can be channeled to a fuel cell for electrical energy generation,” said lead researcher Dr. Shani Elitzur of the Technion Faculty of Aerospace Engineering. “This technology offers a good solution to several challenges, such as hydrogen storage, without the problems associated with storing hydrogen in a liquid or gas state.”

To circumvent the common issues around the storage of hydrogen, the researchers used Proton Exchange Membrane (PED) fuel cells and a process of aluminum activation patented by the research duo: Professor Alon Gany and Dr. Valery Rosenband.

The spontaneous and sustained reaction takes place when a small fraction of a lithium-based activator diffused in the aluminum bulk changes the protective properties of the oxide or hydroxide film which covers the aluminum particle surface.

The heat generated during the chemical reaction could be used to heat water and food in the galley, for de-icing operations, or to warm up aircraft fuel prior to starting the engines.

Furthermore, the technique works equally well with wastewater, meaning there would be no need to carry additional water on board.

Some of the benefits of hydrogen production in-flight listed by the authors include: quieter operations on board an aircraft, significant reduction in CO2 emissions, more efficient electric power generation, and superior thermal efficiency.

“The possibility of using available, on board wastewater boosts both the efficiency and safety of the system,” explained Dr. Rosenband. “Also, the PEM fuel cells exhibit high efficiency in electric energy generation”.

According to Elitzur and Rosenband, fuel cells could even be used in airline and airport ground support operations, such as de-icing and runway light towers.

“Efficient hydrogen production and storage represents the future for efficient and safe aircraft inflight energy needs,” concluded Prof. Gany.

Source: ats.org.