In April, leaders from across the global aviation industry – associations, aircraft manufacturers, engine manufacturers, airlines, airport companies, and air traffic control providers – affirmed their and their companies’ and organisations’ commitment to combating global climate change. They did so in a document entitled ‘Aviation Industry Commitment to Action on Climate Change’.
“As leaders of the aviation industry,” it states, “we recognise our environmental responsibilities ... Therefore, we, the undersigned aviation industry companies and organisations, declare that we are committed to a pathway to carbon-neutral growth and aspire to a carbon-free future ... We urge all governments to participate ... Our efforts and commitment to work in partnership with governments, other industries and representatives of civil society will provide meaningful benefits on tackling climate change and other environmental challenges. We strongly encourage others to join us in this endeavour.”
In the commitment, the industry assures that, in accordance with the fourfold strategy unanimously adopted at the 2007 Assembly of the International Civil Aviation Organisation (ICAO), it will pursue the development and deployment of new technologies, including cleaner fuels; further improve aircraft fuel efficiency, the way aircraft are flown, and the management of ground operations; improve airport infrastructure, air traffic management and air routes; and institute “positive economic instruments” for the reduction of greenhouse-gas emissions, “wherever they are cost effective”.
But governments also have to do their part. The aviation industry companies and associations urge governments to support and help finance research and development (R&D) into greener, breakthrough technologies; to urgently act to improve the design of their airspace use, including such matters as allocation of airspace to civil and military flying, improvement of air traffic control infrastructure, and better procedures for approving necessary airport improvements; and to develop and apply a global emissions management framework for aviation, through ICAO, that is equitable and stable, and in agreement with the United Nations (UN) road map adopted in Bali, Indonesia, in December 2007.
To sum up, the industry promises to “build on the strong track record of technological progress and innovation that has made our industry the safest and most efficient transport mode; and accelerate action to mitigate our environmental impact, especially with respect to climate change, while preserving our driving role in the sustainable development of our global society.”
Environmental Impact
In terms of its environmental impact, aviation affects the climate through its emissions. The industry’s main emissions are carbon dioxide (CO2), water vapour (H2O) and nitrogen oxides (NOx). Aircraft also generate noise and consume fuel – CO2 emissions are directly proportional to the amount of fuel burnt – and there is also the question of their disposal at the end of their lives. In addition, the process of manufacturing aircraft has its own environmental footprint.
According to the UN Intergovernmental Panel on Climate Change, aviation accounts for 2% of global CO2 emissions and this could increase to 3% by 2050. The October 2006 ‘Stern Report’ by Sir Nicholas Stern, commissioned and endorsed by the UK government, states that all forms of transport combined are responsible for 14% of such emissions; agriculture and industry also account for 14% each, power generation for 24%, ‘land use’ for 18%, buildings for 8%, ‘other energy related’ for 5%, and waste for 3%. In terms of land use, airport infrastructure occupies only 1% of the land used for transport systems, while railways take 4% and roads 83%.
Going Green
The global aviation industry is not a "Johnny-come-lately" when it comes to reducing its environmental impact. Airbus’s head of sustainable development, Philippe Fonta, points out that the industry has reduced the noise generated by commercial aircraft by 20 decibels compared with that of equivalent aircraft in the 1970s, and this has resulted in a 75% decrease in noise annoyance caused by commercial aviation.
There has also been a 90% reduction in unburned hydrocarbon and smoke emissions as well as a more than 50% reduction in carbon monoxide emissions from aircraft. The amount of fuel consumed has been reduced by 70% over the last 40 years, and the amount of CO2 emissions has also been reduced by 70% over the same period. “There aren’t many industries that can talk about reducing fuel consumption by 70% over 30 or so years,” points out Leahy. “No other industry is doing so much to reduce its impact on the environment.”
Nevertheless, the aviation industry, in general, has committed itself to do even better. The industry objectives include a further 50% reduction in noise by 2020, in comparison with 2000 levels, and, likewise, a 50% reduction in aircraft fuel consumption and CO2 emissions, as well as an 80% reduction in NOx emissions over the same period. “We have to learn to do more with less, not do less. If we ever are to address environmental issues, it won’t be by adding costs,” stresses Leahy. “Many measures that help the environment also increase efficiency and reduce costs. The best approaches are those that benefit airlines, passengers and the environment.” “We need to keep growing, but with less environmental impact,” says Fonta. “Aircraft will only be accepted if they are efficient in terms of the environment. We have to keep technology at the heart of our programme to improve our performance.”
Aviation companies are also pursuing many other technologies to increase efficiency, and reduce fuel consumption and emissions from aircraft. These include:
- fuel cells to replace jet fuel powered auxiliary power units, which provide power to the aircraft on the ground when their main engines are not running;
- electric motors fitted to the undercarriage wheels (so that aircraft can taxi without having to use their main engines);
- refined aerodynamics (itself requiring improved design and development software, materials, and manufacturing processes); and
- radical new designs of engines and aircraft.
Alternative fuels are also being investigated, such as gas-to-liquids produced synthetic fuels (now under early test) and possible second-generation non-food biofuels (First-generation biofuels cannot be used because they have too low an energy content for aircraft). Second-generation biofuels might be available by 2020, and a fuel mix including 30% biofuels might be in service by 2030.
Companies are also seeking to make their manufacturing processes more environmentally friendly. Airbus, for example, was awarded ISO 14001 certification in June last year. It has stated targets to reduce energy and water consumption and waste emissions from its industrial processes by 2020.
These targets are:
- a 30% reduction in energy consumption;
- a 50% reduction in CO2 emissions;
- a 50% reduction in water consumption;
- a 80% reduction in water discharge;
- and a 50% reduction in waste production.
The benefits from the savings will be invested in research and technology (R&T) for green aviation technologies. The company has committed itself to increasing its R&T budget by 25% from 2008.
Source: http://www.engineeringnews.co.za