Novel fuel sources for Business aviation
As we enter the third decade of the century, the focus on environmental and wider sustainability responsibilities within civil aviation becomes more acute, this of course includes Business aviation. This is further heightened as the sector recovers from the Covid-19 pandemic, which has also been linked to improved environmental performance.
To this end, the Business aviation sector must seek opportunities to further supplement the improvements it has already made to date through the Business Aviation Commitment on Climate Change (BACCC) and take advantage of current opportunities and r future mechanisms towards reaching the 1.5 degree scenario as described in the 2019 Intergovernmental Panel on Climate Change (IPCC) report and the 2015 Paris Agreement. Is it now time to supplement sustainable aviation fuel (SAF) with other novel fuels or propulsion systems for the future of Business aviation?
The Options – SAF, Electrification and Hydrogen
The recent ICAO Stocktaking Seminar heard from a wide range of stakeholders from both within and outside of the aviation industry who presented and discussed ways that the industry could decarbonise. While there are many opportunities for aviation to reduce the overall amount of CO2 it produces, there were other areas within these discussions that could change aircraft propulsion as we currently know it. While SAF is still a significant talking point and a technology beginning to make headway, it could now be joined by electrification, including hybrids and hydrogen. What does this mean from a Business aviation perspective?
Available now, SAF is making its way into the aviation system as a drop-in fuel, including Business aviation and as supply and uptake increases, its use will continue to grow. Most importantly it’s available now, so the CO2 reductions are immediate. There may also be a point in time where there will be certification to fly with 100% SAF, rather than the current blend limit of 50% allowed today. On the downside, Business aviation uses a much wider number of airports that may not be able to have or supply SAF in the foreseeable future with the current limited supply capability.
Electrification in terms of Business aviation is a viable prospect in the future, given the sizing and distances travelled by a significant portion of the sectors’ aircraft, but could be 5-10 years before making a significant difference in its contribution to the lowering of CO2 outputs and if charging of the batteries is via renewable energy, this contributes to the overall reduction of emissions, including noise. On the downside with battery-powered aircraft will be the infrastructure question, can I charge my battery at my destination airport, how long will charging take before I can make my return journey, will there be a spare supply of batteries that I can swap out?
Hydrogen is the next option. There are two ways to deliver hydrogen into an aircraft system, one is through a modified gas turbine engine, similar to what you see on current aircraft, the other is through fuel cells. Both hydrogen options will require a redesign of the aircraft to accommodate the need for storage tanks, with the fuel cell version requiring significant sized hydrogen storage tanks. Both offer at least a zero-carbon outcome but do have non-CO2 emissions that require further research as to their impacts. As there is with electrification, changes to the aircraft handling infrastructure will be needed together with the capability at smaller airports. The other significant change will need to be how hydrogen is produced in the future, from technologies such as carbon capture and storage, rather than fossil fuels that produce it today.
What’s the best fit for Business aviation and what’s the art of the possible? Given the merits of all three technologies, it could be all three. Smaller and short-range aircraft being battery-powered, mid-size and mid-range aircraft being powered with hydrogen and long-range aircraft with sustainable aviation fuels, or some with a combination of technologies. It may be some time before we see some of the more sophisticated technologies that will need to be brought to the appropriate technology readiness level and that all safety considerations are considered and met.
If the Business aviation is to meet its CO2 goals as it has set out in the BACCC, it may be time to consider these different options in addition to SAF to power the sectors’ aircraft and move away from the current “one size fits all” way that aircraft are powered now with kerosene. There are challenges ahead and questions to be answered towards achieving this from many quarters, however, the Business aviation sector has always been an innovator and a first adopter of new technology. How long will it be before we see different skies above?