Carbon Footprint Airports

Transcription

1 December 2013 Carbon Footprint Airports Whole-life carbon analyses of Heathrow and Gatwick Gatwick Airport for Terry Farrell Partnership Gatwick Airport Limited by Sturgis Carbon Profiling LLP TM

2 Contents Contents and index 2 Executive summary 3 1 > Introduction 5 2 > Study methodology 6 3 > Embodied carbon emissions 8 4 > Operational carbon emissions 11 5 > Whole life emissions 14 6 > References 16 TM 2

3 Executive summary Sturgis Carbon Profiling was commissioned by Terry Farrell Partnership and Gatwick Airport Limited to produce an indicative Carbon Footprint assessment of three of the options presented in August to the Davies Commission by Heathrow and Gatwick Airports: Heathrow North-West > 3500 m runway in the North West of current airport s limits > Extensive works in the M25 > Extensive residential, commercial and infrastructures demolitions in Harmondsworth and Longford > New T6 and redevelopment of terminals 1, 2 & 3 Heathrow South-West > 3500 m runway in the South West of current airport s limits > Extensive works in the M25 and other access infrastructures > Residential demolitions in Stanwell Moor and substantial modification of water reservoirs required > New T6 and redevelopment of terminals 1, 2 & 3 Gatwick South > 3500 m runway in the South of current airport s limits > New terminal building and reorganization of ancillary and train station > Limited demolition of existing properties. Main objectives > Quantification of the CO 2 e emitted by current airport facilities > Estimation of the CO 2 e emitted in the construction and operation of the proposed three configurations > Comparison and assessment of each of the proposed solutions in terms of CO 2 e emissions > Contextualization of main results Carbon emissions: Results Airports Configuration Embodied carbon emissions Operational carbon emissions Whole Life impact in 35 years Heathrow North West 5.54 MTnCO 2e 1.76 MTnCO 2e/year MTnCO 2e Heathrow South West 6.65 MTnCO 2e 1.82 MTnCO 2e/year MTnCO 2e Gatwick South 3.78 MTnCO 2e 1.74 MTnCO 2e/year MTnCO 2e TM 3

4 Key findings of the report 1 > Total Emissions: Both the operational and embodied carbon emissions in Heathrow schemes are higher than in Gatwick. 2 > Embodied emissions: The embodied carbon of Heathrow s least emitting proposal is still 40% higher than Gatwick s scheme. The difference is 1,756,000 Tones of carbon emissions Million Tons of CO2 are the emission that would be released by flying three quarters of a million people from London to Hong Kong 3 > Operational emissions: Even though Gatwick is further away from London, the total amount of operational emissions in Heathrow is higher because aircrafts ground movements will be longer. Caveat 1 > Integrated Traffic Analyses: Variable operational carbon figures need to be checked in a GIS model where travelers dynamic preferences and postcode based CAA passengers origin data will be implemented. Current whole life cycle results (see section 5) show that the differences between schemes do not define a clear best option in the long term and more detailed analyses could actually change current tendencies. Next steps 1 > Stansted +1: Other options presented to the Davies Commission (Kent County Council, 2013) proposed an additional runway in Stansted. The embodied carbon of adding this extra runway has been roughly calculated to be 10-20% higher than Gatwick s proposal. However, more detailed topographic analyses and the influence of operational emissions might vary these results: Stansted is further away from London, but potentially closer to other UK regions, for example. 2 > Integrated Traffic Analyses: As already defined, this would include a GIS model with postcode based CAA passenger s origin data, passengers switching and preferences modelling, demographic and income data and isochrones development for a fully detailed comparison of operational emissions. TM 4

5 1. Introduction Heathrow (2013b) and Gatwick (2013) presented in August their proposals to the Davies commission to expand these airports and allocate more capacity. Three of these options two from Heathrow and one from Gatwick propose similar extra runways operating in independent mixed mode, which would provide service to roughly 45 million extra passengers. The decision on where to implement this capacity increase will need to consider different factors, including the environmental impact. The construction of an extra runway would imply the rise of carbon emissions in each of the airports. However, this increase would not necessarily be proportional to the extra capacity of the airport because current airports conditions, location of the new runways and scope of the proposals are different. The carbon emissions associated to both the construction and operation of new facilities will contribute to climate change and their long term impact should be assessed. Sources of CO2 > Construction, upgrade and use of airport facilities > Construction of facilities directly associated to the airport activity: logistics, services, commercial, hotels, car parks > Demolition of existing buildings and infrastructures within and outside current airport limits to construct the new runway and associated airport facilities. > Reconstruction of any demolished facility associated to the airport required to meet the demands of the new capacity. > Construction and upgrade of new connecting infrastructures > Commuting to / from the airports TM 5

6 2. Study Methodology This report has been produced in accordance with ISO 14044:2006 (ISO, 2006a). The Life Cycle Assessment (LCA) outlined in this document has been verified internally by Sturgis Carbon Profiling LLP but not by any external third party. 2.1 Methodology The Life Cycle Assessment (LCA) is a framework used to measure and evaluate the environmental impacts associated with a building throughout its life cycle. Its focus is on the environment impacts from extraction of raw materials, through processing, manufacture, refurbishment to eventual end of life and disposal. This analysis adheres to the ISO standards on LCA, ISO 14040:2006 (ISO, 2006b) and ISO 14044:2006, which were developed in response to increasing interest in environmental protection; the possible impacts of manufactured and consumed products and the need to better understand and address these impacts. Please refer to our previous report (Sturgis Carbon Profiling, 2013) for complete details. The following summary charts illustrate the main stages of carbon emissions in the life cycle of a building: Categories > Product Manufacture: Carbon arising through production process > Construction: Carbon arising through site works, etc > In Use: Carbon arising through heating, lighting, cooling, ATMs within the airport, airport vehicles, workers commuting and repair/replacement > End of life: De-construction of building and infrastructures following proposals definitions, not including any recycling potential values. > Transport in use: Commuting of passengers to/from the airport Life Cycle Assessment stages TM 6

7 2.2 Definitions Carbon Emissions Carbon dioxide and the bundle of green house gases (i.e. carbon dioxide equivalents such as methane), the unit of measurement of which is KgCO 2 e or TnCO 2 e Embodied Carbon Emissions Emissions that are created through construction, transportation, assembly, maintenance and eventual deconstruction of a building. From the described methodology (see previous section) it includes Product and Construction Stages and part of the In-Use stage. Operational Carbon Emissions Emissions associated with heating, cooling, lighting and power needs of buildings. I.e. the emissions linked to the using of a building or space. In this report operational emissions also include the emissions associated to the commuting of the building users, the airport s vehicles movement within the premises, the take-off, landing and taxiing of aircrafts, waste and water. Fixed Operational Carbon Emissions In this report, they are the part of the Operational Emissions which do not vary depending on the location of the building. Variable Operational Carbon Emissions In this report, they are the part of the Operational Emissions which depend on the location of the building or any of its elements, i.e. the commuting of airport users to / from the airport and aircraft s ground movements. 2.3 Data In completing the Life Cycle Assessment, we have used the following data sources, amongst others (see Reference section): The details on Heathrow s and Gatwick proposals to the Airports Commission are based on o Heathrow s report to the Davies Commission (2013b) o Gatwick s report to the Davies Commission (2013) Current and future estimations of passengers and airports capacity are based on o UK Aviation Forecast report, Department for Transport (2013b) o Transport Statistics Great Britain, Department for Transport (2013a) o CAA Passenger Survey (2011) o CAA Annual Statistics (2012) o Airport Capacity data from Greater London Authority (2013) Airport facilities, infrastructures and associated uses embodied emissions are estimated based on o Built area quantification of Heathrow and Gatwick by Sturgis Carbon Profiling LLP o Built area quantification of associated uses (industrial, commercial, hospitality, parking ) by Sturgis Carbon Profiling LLP o Component database of Sturgis Carbon Profiling LLP o The Inventory of Carbon and Energy (ICE) University of Bath, BSRIA (2011) o Life Expectancy of Building Components, BCIS (2006) Building operational emissions are estimated based on o Heathrow and Gatwick s Climate Change and Sustainability reports (Heathrow, 2010, 2012; Gatwick, 2009a) o CAA Passenger Survey (2011) o UK Aviation Forecast report, Department for Transport (2013b) CEN M350 Carbon Calculation Methodology, CEN/TC350, Construction Resources and Waste Roadmap (CRWP) (2010) Whole Life Carbon Footprinting Measurement & Offices, Sturgis Carbon Profiling, JLL, BCO (2012), TM 7

8 3. Embodied Carbon Emissions Emissions that are created through construction, transportation, assembly, maintenance and eventual deconstruction of a building. From the described methodology (see section 2 of this report) it includes Product and Construction Stages and part of the In-Use stage. The main areas of study are: > Facilities and associated uses already constructed (CO 2 e already emitted) > Demolition of existing buildings and infrastructures (including residential). > New Airport facilities and associated uses. Maintenance and upgrade of existing facilities. > Reconstruction of demolished facilities which are associated to the airport (excluding residential) > Land reclamation, drainage or movements. > New commuting infrastructures A Methodology > Delimitation, vectorization and quantification of GFA of current airport facilities and areas directly dependent on airport activities. Quantification of the carbon emissions already emitted, based on the requirements of CEN/T350 methodology. > Estimation of the volume of wetlands and reservoirs to be drained, filled and flatten within the proposed extension areas, as well as the excavation of replacement reservoirs. Quantification of the amount of materials required and carbon emissions associated. > Estimation of the buildings and infrastructures that would be demolished according to the scope of the proposals presented to the Davies Commission. Calculation of the carbon emissions that the demolition process would release. > Quantification of the length and level of improvement required in existing infrastructures. Calculation of the associated emissions in the expected upgrading works. > Calculation of modules per passenger / ATM following the airport s new capacity requirements for every type of building. Estimation of the areas of airport facilities and associated uses which the upgraded airports will require. This will include the reconstruction of the airport facilities and associated uses which have been demolished in the expansion process, but will exclude the relocation of uses not related to aviation activities (residential, local retail, farms ). Quantification of the carbon emissions emitted in this process, based on the requirements of CEN/T350 methodology. B Assumptions and limitations > Any new runway is expected to provide service to 45 million passengers more. Besides, aviation forecasts (DfT, 2013) add further demand by 2050 which has also been considered in the estimation of new required infrastructures. > Both Heathrow s schemes propose major reconversions in their existing terminals and aprons (T1-2-3). The additional capacity for 45 million passengers cannot operate from one new terminal or extension. New proposed T6 will only serve up to 25 million passengers. New demand will need to be distributed amongst all the existing, new and reconverted terminals. Therefore, this report has to include the emissions associated to the major changes in existing terminals and aprons, accfollowing the layouts presented to the Davies Commission by the Airport (Heathrow 2013c). > In current London airports, associated uses are scattered in different areas around the airport. This report assumes a compact efficient planned layout for the associated uses in any new development. > Upgrade tracks on existing Heathrow Express line to improve performance and capacity. TM 8

9 > Upgrade tracks on existing Gatwick Express line to improve performance and capacity. > Upgrade of Paddington and Victoria stations to accommodate increase capacity requirements. > Modification of different sections of the M25 and other highways to allocate more traffic, and improvements of the connections to other major UK cities have not been considered. > Upgrade of tracks includes the substitution of the tracks and electrification, but does not include any further soil preparation, levelling or tunnel construction. > Airports are in continuous evolution during their whole life. Terminals are extended, partially demolished, reconverted but these changes do not normally affect the existence of the whole complex. C Issues to consider > The construction of any of the schemes proposed in Heathrow would emit more carbon than the Gatwick South. In particular, Heathrow North-West would emit 46% more carbon, and Heathrow South-West, 76% more. > The demolition in each proposal is a key factor that affects twice. Firstly, the amount of carbon released in the demolition process is around ten times higher in Heathrow s schemes than in Gatwick s: The area around Heathrow is more densely populated and Heathrow proposes the demolition of a higher proportion of their existing facilities. Besides, the airport facilities and associated uses which are demolished in this process will need to be reconstructed, because the service they provide is still required by the new demand. These factors increase the total emissions in 1,000,000 Tonnes of CO2e in both Heathrow s schemes. > 1 Million Tonnes is the carbon that would be emitted in the construction of 12,500 new homes. > Filling and replacing the reservoirs in the South-West option would emit 584,000 Tonnes of CO 2 e. > The works in these fresh water reservoirs will emit more carbon than would be released in the desalination of sea water suitable for the annual consumption of more than 9,140,000 people. That is more water than all London needs annually. > The substantial works required in the M25 and the new proposed infrastructures around Heathrow also contribute to much higher emissions. Emissions due to the adaptation of the infrastructures to the new schemes are 3 to 4 times higher in Heathrow than in Gatwick.. TM 9

10 AIRPORT LIMITS ASSOCIATED USES SCOPE OF PROPOSED EXTENSIONS MAIN DRAINED AND FILLED AREAS DEMOLITION REQUIRED INFRASTRUCTURES + RECONSTRUCTION HEATHROW NORTH WEST HEATHROW SOUTH WEST GATWICK SOUTH Quantification of Embodied carbon emissions Tonnes CO 2e [+45 million passengers] Heathrow North-West EMBODIED EMISSIONS Heathrow South-West Gatwick South Demolition of affected areas (including residential) 339, ,000 31,000 Drain wetlands and fill/replace reservoirs 7, ,000 10,000 Construction of new airport facilities and associated uses 3,145,000 3,133,000 3,001,000 Construction / modification / upgrade of infrastructures + Reconstruction of demolished facilities (only airport related) 2,051,000 2,644, ,000 TOTAL Embodied Emissions 5,542,000 6,649,000 3,781,000 Emissions emitted by existing airport facilities and associated uses at 95% capacity 4,150,000 (69.2 million PAX) 4,150,000 (69.2 million PAX) 2,036,000 (33.3 million PAX) TM 10

11 4. Operational Carbon Emissions The Operational Carbon emissions emitted by each configuration have been quantified considering if they are influenced by the airport or runways location (variable emissions) or they are not (fixed emissions). 4.1 Fixed operational carbon emissions Fixed operational carbon emissions comprise all the CO 2 emitted within the airport facilities which for the same amount of passengers / ATMs do not depend on the airport location or the characteristics of the proposal. Emissions include: > Aircrafts taking off and landing, > Emissions from airport vehicles and equipment, > Electricity, gas, refrigerants, waste and water usage > Emissions from staff travel to and from the airport A Methodology > Deduction of fixed emissions per passenger based on latest data from Heathrow (2012) and adjusted with latest emissions data from Gatwick (2009a&b) and Stansted (2013a&b) > To keep the proposals in comparable terms, the operational emissions have been calculated for a 45 million extra passengers, following the figures proposed to the Davies Commission by both Gatwick and Heathrow reports. > Calculation of carbon footprint based on the requirements of CEN/T350 methodology B Assumptions and limitations > The report assumes that the staff s average commuting distance and emissions travelling to / from the airport will remain constant regardless of where the airports are located. > All the airports will operate at the same capacity (95%), providing service to the same amount of passengers: 45 million. > This simplified methodology calculates the fixed operational emissions based on the amount of passengers using the airport. As this number is constant in the three schemes, the fixed operational emissions can also be considered equivalent. > In the embodied carbon calculation, emissions associated to the upgrading of current airport facilities have been allowed to improve all airport s efficiency to match similar standards. > London Heathrow (operating at 98% capacity) has been used as the reference airport to forecast the fixed operational carbon emissions. Current emissions from Gatwick (currently operating at 88% capacity) and Stansted (currently operating at 53% capacity) have been considered to adjust the ratios Airport capacity extracted from Department for Transport s data (2013b). TM 11

12 4.2 Variable operational carbon emissions Variable operational carbon emissions are associated to the passengers travelling to and from the airport. These emissions vary significantly depending on the airports location and their catchment areas as well as their connectivity to different transportation hubs and the rail/road networks. These emissions are also directly related to taxiing average distance. Details of each proposal presented to the Commission show that aircrafts ground movement will be up to 37% longer in some of the schemes (Heathrow, 2013c). This factor makes taxiing another variable operational emission which does not depend on the location of the airport in the country, but on the relative location of the runways and the aprons / terminal buildings. A Methodology Passengers Commuting: > Calculation of the amount of people currently going to and from each of the airports. Data from connecting passengers (Department or Transport, 2013b) and waving-off people (CAA, 2011a) considered in the estimation. > Estimation of the distance travelled by each person travelling to/from the airports based in CAA s Passenger Survey (2011), average distances from London and the airports to all UK s regions and direct connectivity of each region with the airport. > Estimation of the amount of people who would go to each airport in the proposed schemes. > Calculation of the emissions forecast based in the amount of people, mean of transport used (CAA, 2011a) and origin/destination. Aircrafts ground movements: > Heathrow estimated the average taxiing distances or each of their proposals in their report to the Davies Commission (Heathrow, 2013b) to benchmark them against other European Airports. Following similar GIS and ground movement analyses, the average taxiing distance for Gatwick South proposal has been estimated. > Calculation of the proportional emissions due to aircrafts ground movement following data from Heathrow (2010, 2011) and average taxiing distances. B Assumptions and limitations > Connecting passengers: This assessment assumes that the proportion of terminal and connecting passengers adding up the figures of the two airports in 2012 remains constant through time. > Waving-off: Improvement in transport infrastructures is expected to allow the same proportion of waving-off companions in both airports. Heathrow s profile in 2011 will be considered (CAA, 2011a) > Mean of transport: Improved infrastructures providing service to a wide range of passenger s profiles would make possible that the proportion of people going to/from different airports using any mean of transport will be the same in every airport. Heathrow is again assumed to be the most adequate existing profile to define these proportions. > Underground: Underground connection for Heathrow has been integrated into rail connection so that it can be assumed that people accessing every airport use different means of transport in the same proportion. TM 12

13 > Distances to UK regions: CAA Passenger Survey (2011) provides simplified data on the region of origin of the passengers for each airport. The average distance to/from each region to the airports has been assumed to be the distance from the most populated urban area of the region. The average travelling distance in regions close to both airports has been estimated from the most populated urban area at county level, proportionally to its population. GIS databases have been used to define the distances. > Access to the airport: In the calculation of the distance from the origin to the airport, direct connections have been taken into account. If there is a train connection to the airport from the chosen urban area either direct or changing train in a middle point it will be assumed that people going to the airport will not transfer in London (National Rail, 2013). Otherwise, passengers using public transport will commute through London and the distances will be updated accordingly for those destinations. 4.3 Results Operational Carbon Emissions Issues to consider > Accessing Gatwick will emit Tonnes CO 2 e / year more than getting to Heathrow. > However, the emissions released by aircrafts taxiing in Gatwick South would be much lower in Gatwick: Aircrafts in Heathrow North-West would emit Tonnes CO 2 e / year more than in Gatwick South, and in Heathrow South-West Tonnes CO 2 e / year more. > In 45 years, Heathrow North-West scheme would emit 0.9 Million Tonnes CO 2 e more than Gatwick, and Heathrow South-West scheme 4 Million Tonnes CO 2 e more. This is more than the carbon which will be emitted in the construction of all Gatwick South scheme. TM 13

14 5. Whole life emissions The assessment of whole life carbon emissions requires to include time as a crucial factor in the analyses. The cumulative character of operational emission have a huge impact when the time frame is considered. A Methodology > The following graph collects critical data calculated in the previous sections to display a combined results summary. B Assumptions and limitations > Fixed Operational emissions: The main objective of this report is to assess the difference in carbon emissions between the three proposed schemes. Fixed operational emissions are constant in the three proposals. However, they are independent of the airport and runways construction and location. In order to provide a clearer representation on the emissions, only embodied and variable operational emissions will be represented in the summary graph. > Time frame: Department of Transport s aviation forecast (2013b) only provide data until Besides, other assumptions like origin of passengers, mean of transport used will be less and less reliable with time. Therefore, the carbon emission will be calculated only until This limit is more than enough to provide a clear view on the initial emissions and their tendency for the future. > End of life: Airports are dynamic infrastructures which are continuously upgrading, adapting and extending their facilities. Therefore, setting a limit for their end of life is not only difficult, but unrealistic. Only the planned de-construction of airport facilities (Heathrow Terminals 1-3) has been included in the summary strictly following the schemes that Heathrow has presented to the Davies Commission (Heathrow, 2013b). C Issues to consider > Relation between Embodied and Operational emissions: The embodied carbon emissions of Gatwick proposal are much lower than Heathrow s. However, the relative importance of these emissions in a whole life carbon perspective is not that relevant. The difference between variable operational emissions will define what option has a lower carbon footprint. > Whole life emissions: In 35 years, Gatwick would have emitted 3.15 million tonnes CO 2 e less than Heathrow North-West (8.3% less) and 5.66 million tonnes less than Heathrow South-West (- 18.9%). That is more than return drives to the moon. > Uncertainty of operational emissions: Results show a very small difference in operational emissions between Heathrow North-West and Gatwick South. This difference defines the whole-life cycle carbon emissions of the options. Small variations in users origin distribution, dynamic preferences or aircraft average taxiing distance might modify the variable operational emissions and switch the tendency between Gatwick and Heathrow. More detailed analyses is recommended. TM 14

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16 6. References Berners-Lee, Mike (2010) How bad are bananas? The carbon footprint of everything. London. Profile Books Ltd. BCIS Building Cost Information Service (2006). BMI Life Expectancy of Building Components. 2nd edition. BCIS, London BCO British Council for Offices (2012) Whole-Life carbon footprint measurement and offices. BCO. London BSI (2013a) PAS 2050:2011 Specification for the assessment of the life cycle greenhouse gas emissions of goods and services [Online] Available at: [Last accessed: 31st July 2013] BSI (2013b) BS EN Sustainability of construction works. Assessment of environmental performance of buildings. Calculation method [Online] Available at: [Last accessed: 31st July 2013] BSRIA and University of Bath (2011) Embodied Carbon. The inventory of Carbon and Energy (ICE). BSRIA, Bracknell, Berkshire. CAA Civil Aviation Authority (2011a) CAA Passenger Survey Report 2011 [Online] Available at: [Last accessed: 31st July 2013] CAA Civil Aviation Authority (2011b) Catchment area analysis [Online] Available at: [Last accessed: 31st July 2013] CEN European Committee for Standardization (2010) CEN/TC 350 Sustainability of Construction Works. [Online] Available at: CENTechnicalCommittees/Pages/WP.aspx?param=481830&title=CEN/TC+350 [Last accessed: 31st July 2013] Department of Transport (2013a) Transport Statistics Great Britain 2012 [Online] Available at: [Last accessed: 31st July 2013] Department of Transport (2013b) UK Aviation Forecasts. [Online] Available at: [Last accessed: 31st July 2013] Department of Transport (2013c) AVI01 - Air traffic at UK airports. Table AVI Mode of transport to selected UK airports: time series [Online] Available at: [Last accessed: 31st July 2013] Gatwick (2009a) Gatwick Airport: Climate Change Report [Online] Available at: Report_2008.pdf [Last accessed: 31 st July 2013] Gatwick (2009b) Sustainability Performance Review [Online] Available at: rformance%20review% pdf [Last accessed: 31 st July 2013] TM 16

17 Gatwick (2013) Airports Commission: Proposals for providing Additional Runway Capacity in the Longer Term [Online] Available at: g_gatwick/gatwick_airport_proposals_for_additional_longterm_runway_capacity19jul2013.pdf [Last accessed: 5th December 2013] GLA Greater London Authority (2013) Airport Capacity in London. [Online] Available at: [Last accessed: 31st July 2013] Heathrow (2010) Towards a sustainable Heathrow. A Focus in Climate Change [Online] Available at: [Last accessed: 31 st July 2013] Heathrow (2012) Towards a sustainable Heathrow Sustainability performance summary [Online] Available at: y.pdf [Last accessed: 31 st July 2013] Heathrow (2013a) Airports Commission Discussion Paper 03: Aviation and Climate Change. Heathrow Airport limited response [Online] Available at: 1 [Last accessed: 31 st July 2013] Heathrow (2013b) Airports Commission: Long-term hub capacity options [Online] Available at: [Last accessed: 5th December 2013] ISO - International Organization for Standardization (2006a) ISO 14044:2006 Environmental management Life cycle assessment Requirements and Guidelines [Online] Available at: [Last accessed: 2nd August 2013] ISO - International Organization for Standardization (2006b) ISO 14040:2006 Environmental management Life cycle assessment Principles and framework [Online] Available at: [Last accessed: 2nd August 2013] Kent County Council (2013) Airports Commission Proposal for providing additional airport capacity in the longer term. [Online] Available at: procedures-and-plans/plans/aviation%20strategy/kent%20county%20council%20- %20proposal%20for%20additional%20airport%20capacity%20in%20the%20longer%20term.pdf [Last accessed: 5th December 2013] National Rail (2013) National Rail Enquires [Online] Available at: [Last accessed: 2nd August 2013] Sturgis Carbon Profiling (2013) Carbon Footprint Airports: A proposal to identify the benefits from networked solution to meeting London airport capacity shortage. London. Submitted to Gatwick Airport on September TM 17