The Sky’s the Limit An overview of prospects for aircraft emissions and strategies for their control Mark Barrett Februa

1. The Sky’s the LimitAn overview of prospects for aircraft emissionsand strategies for their controlMark BarrettFebruary 2007

2. Outline • Aviation system and environmental impacts • International overview • Demand • Emission control options • Base scenario and global warming • Emission control scenarios • Taxing aviation • UK aviation in context with other sectors • A local note The global studies this lecture is based on are 10-15 years old, but the picture is unchanged except we have ‘advanced’ 15 years further along the high growth aviation scenario. More recent energy scenarios for Europe confirm the importance of aviation as compared to other sectors. Reports and other material on aviation may be found at: http://www.bartlett.ucl.ac.uk/markbarrett/Transport/Air/Aviation.htm

3. Overview of system

4. Global environmental impacts STRATOSPHERE Ozone depletion? water global cooling? clouds nitrogen oxides ozone formation global warming (2 to 4 to 15%?) carbon dioxide Other sulphur, soot... TROPOSPHERE

5. Global warming impact and altitude

6. The international dimension Fuel Traffic • 2 billion passengers on 47000 aircraft • USA 40% of demand and fuel • 5-6%/yr growth outlook; fastest in Asia

7. The international dimension

8. Wealth, demand and fuel use

9. Demand structure

10. Freight demand UK air freight composition

11. Fuel consumption: base case

12. Aviation and global carbon Business as usual aviation is incompatible with climate stabilisation

13. Physical control measures Engine Freight Airframe CONTROL MEASURES Demand management Technology Business Aircraft size Passenger Leisure Speed Operation Traffic control Altitude Route length Load factor

14. Policy measures Demand • Telecommunications • Local’ leisure markets • Transfer of freight to surface modes Technology • Better engines, airframes Operation • Increase occupancy factors • Air traffic control

15. Freight demand management

16. Effects of technical and operational measures

17. Alternative fuels? • Engines driven by combusted chemical fuels the only option • Current engines of proven reliability – important in aircraft! • Even if no net CO2 is produced, these fuels produce water and NOx which cause global warming. • Biofuels • Very limited biomass • Conversion of biomass to high grade liquid fuels – efficiency ~0%? • Hydrogen. • Expensive renewable electricity for form H2 at ~70% efficiency • Hydrogen energy density low so major redesign of aircraft required. • Synthetic kerosene from renewable electricity? • Where does the carbon come from? • What would the efficiency be? • No obvious prospects for renewable fuels. The probability is that aviation will be the last sector to give up fossil fuels.

18. Scenarios

19. Policy implementation Taxation • Emissions, fuel, aircraft movement, passenger/freight movement Regulation • Emission limits for aircraft and for high altitude pollutants • Altered regulation of commercial operation • Planning at local, national and international level • Emission trading Investment • in telecommunications, local environment, other modes, better aircraft, air traffic control Intelligence • advertising, technical advice

20. Policy implementation: details Control measures

21. Ownership and control of the aviation problem International transport (aviation and shipping) subject to international treaties and multilateral negotiations. The problematic results of these are: • International transport (aviation and shipping) emissions not allocated to States so they are not included in the Kyoto protocol. They are called “bunker fuels and emissions.” • It is not possible for an individual State to separately apply taxes or other constraints to international in-flight items such as fuel or emissions. • Technical standards for aviation are set by negotiation through the UN body, ICAO. States can: • Influence the environmental performance of aircraft using State airports. • Apply taxes to tickets • Apply charges to Landing and Take Off (LTO) • Apply regulation to the airport environment • Influence demand and the provision of alternative modes

22. Example of cost change

23. Costs and flight length

24. The Effects of Taxing AviationPossible charge points

25. Taxes and responses Operator response = change in cost . proportionate response

26. Model schema

27. Fuel consumption: zero taxation case

28. Average passenger costs in scenarios

29. Scenarios: demand

30. Scenarios: fuel burn

31. Tax study conclusions o Aviation system complex; modelling simple o Base scenario: demand increases 600% and fuel use by 400% in 40 years o Fuel charges reduce fuel consumption and related pollutants by 3 to 20% o Operator response may make an important contribution to emission control o Fuel charges may have a significant effect, but will not prevent large increases in pollution emission oModel should be refined, especially demand and operator response aspects oOther charges should be explored oThe framework for charging and emission allocation needs clarifying

32. Current EU25 scenarios: UK: Passenger demand from PRIMES

33. UK: Passenger transport fuel

34. UK: CO2 emissions

35. Greenhouse gas, mode and distance

36. Conclusions • Aviation has significant environmental impacts • Aircraft emissions will grow even with all control measures except demand management strongly applied • Aviation should be subject to limits as tough as other sectors - or maybe tougher as it’s mainly a leisure activity • Demand growth is fundamental driver • Leisure travel is the biggest segment of demand. • The USA accounts for 40% of demand, fuel use and emission Assume : • doubled global population • 50% reduction in global carbon emission • equal rights to emission then emission quota of about 0.4 tC/person/year for all activities which is one return flight between UK and USA each year, or between UK and Spain including high altitude effects.

37. Local environmental impacts

38. Air quality Heathrow Terminal 5

39. Global and Local Main local environmental impacts • Aircraft: noise; emissions generally small effect on local air quality • Surface transport to airport : pollution, noise, land take... Interaction between global and local • Less demand: less airport capacity • Larger aircraft and less empty seats: less aircraft movements, maybe less noise • More airport capacity: more scope for demand increase, but less congestion Local policies • Local planning requirements: numbers and timing of aircraft/passenger movements; operations; surface transport; ...... • Airport operation: charges, time of day • Airport capacity location: given the need for capacity, where should it be? Aircraft have to land somewhere Currently most duties and powers are at domestic/local level

40. Possible EU policy measures Emission trading Allocation of emissions from international flights Global technical standards for all pollutants Market regulation: liberalisation, deregulation Route negotiation and airport slot allocation Allow scope for appropriate fiscal measures Development of long distance transport infrastructure Telecommunications Freight switch Decreased subsidies ‘Local’ leisure markets