Sector Category Measure Potential Improvement
Aviation Operations Advanced communications, navigation and surveillance (CNS) and air traffic management (ATM) 5%
Airframe Design and Propulsion More efficient turbofan engines, Unducted fan engines, Advanced lightweight materials, Improved aerodynamics, New airframe designs 30%
Alternative Fuels Medium term: Biofuels; Long term: Biofuels, Hydrogen 25%
Maritime Operations Speed reduction, Optimized routing, Reduced port time 45%
Ship Design and Propulsion Novel hull coatings and propellers, Fuel efficiency optimization, Combined cycle operation, Multiple engines 35%
Alternative Fuels and Power Marine diesel oil (MDO), Liquefied natural gas (LNG), Wind power sails 40%
Source: adapted from D. McCollum, G. Gould and D. Greene (2009) Greenhouse Gas Emissions from Aviation and Marine Transportation: Mitigation Potential and Policies, Pew Center on Global Climate Change.
Note: Potential improvement is an approximate figure of expected energy savings for operations by 2050.
Potential to Reduce Energy Consumption in Air and Maritime Transportation
Energy consumption is a dominant component or operating costs for both air transportation and maritime shipping. There are thus strong incentives to innovate if this innovation is cost effective and leads to notable improvements.
  • Air transportation. Most air traffic control systems are obsolete, so it is expected that new generation systems would help avoid undue delays for takeoff and landing. Air transportation has a tradition of fuel efficiency improvements as each new generation of aircraft comes with the latest improvements in aircrafts design, propulsion and materials. Additionally, the retirement of older aircrafts and their replacement with new ones gradually improves the overall efficiency. Switching to biofuels and even to hydrogen on the long term is also a possibility.
  • Maritime transportation. The range of options for maritime transportation is somewhat limited. "Slow steaming" is an alternative but requires a greater number of ships, particularly over long distance pendulum routes. Economies of scale have been quite effective at improving the maritime shipping efficiency for unit of cargo carried. Still, improved ship design, better engines and alternative fuels could lead to long term improvements. However, since ships are assets that have a long life cycle, improvements will be very gradual.