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How did we work out the costs?
We have shown here how we calculate the emissions for our upper class passengers only, but the equation can of course be altered to produce the emissions for our other classes of passenger. The actual emissions data we have used here, is taken from our 2006 fuel uplift figures, i.e. the amount of fuel we actually put into our planes for each individual flight and times by the IATA standard multiple of 3.16 to provide us with the total CO2 emissions for that particular flight. We have then used an average for that particular route over the years emissions. We have used our fuel uplift figures because they offer the most accurate record of fuel use for the flight, as we are able to take it from the fuel pump figures when the planes are filled up, which our pilots sign off and then we receive the invoices for. This is more accurate than taking the records from what is left in the tanks, as different reading may result from different factors such as the warmth of the engine or any uneven surface underneath the plane. We then compare it with fuel burn data recorded by our pilots during the flights to ensure against any discrepancies. Some other offset schemes and companies use the flight distance, using a standard figure for emissions in long and short haul flights, but this does not take into account the fact that the take off and landing period of any flight is more fuel intensive than the cruising phase. It also does not take into account delays or where an indirect flight path is taken, which can all increase the amount of fuel used and therefore CO2 produced. The multiplier is used here as an indicator of non-CO2 impacts, such as NOx, water vapour and sulphate and soot particles. There is currently ongoing discussion as to whether the impacts of aviation are wider than CO2 impacts alone. We have used a factor of 1 in this equation because there is still much discussion about these effects. Defra, similarly does not use a factor in its latest carbon calculator (June 2007) and currently states “Non-CO2 effects such as from Radiative Forcing from NOx and water vapour emissions are not factored into the calculation on the advice of DEFRA’s aviation consultant and others. This is because of the uncertainty and ongoing scientific research and debate around the scale of these wider impacts”. (1) The University of Reading also state that “It is premature to include non-CO2 effects of aviation in emissions trading schemes” in their paper of the same name. (2) Also in Friends of the Earth’s recent report produced by Tyndall Centre (3) states that “Not to say that these emissions are not important, merely that the use of the radiative forcing uplift factor is at best confusing, and at worse could lead to policies that are potentially damaging to the climate.” Our objective by including it here is to be transparent about potential non-CO2 effects, and give customers the opportunity to make an informed decision and increase this if they wish. We will review our inclusion of a higher multiplier when there is further evidence and agreement amongst key industry and scientific experts. The other key factor we have used in our equation is weight. As we mentioned earlier, there is a direct correlation between weight onboard and the amount of CO2 produced. We therefore believe this is the key factor which should be used to calculate the different emissions responsibilities between different classes of passengers. Firstly we have taken the actual gross weight of our cargo for each particular route, which is simply the actual weight of everything we have carried in the hold, apart from passenger luggage. We do not believe that those passengers who wish to offset their flights should have to cover the CO2 emissions of those companies for whom we air freight goods. We are also currently developing a cargo offset scheme for those customers to allow them to do just that. Secondly it is a fact that different classes of travel are more efficient in terms of their CO2 production than others. In a Virgin Atlantic plane, the most carbon efficient class is economy class. In upper class, passengers have a more sophisticated in flight entertainment system and seat configuration which weighs more than other class seats. They also have a more generous baggage allowance and more space on the plane. We have therefore taken the passenger number figures for each different class of travel on that particular route, and times them by the actual seat weight (including in-flight entertainment system) of that class plus the IATA standard weight of a passenger and their luggage, which is 100kgs. Of course some of passengers, for example in upper class have a far more generous baggage allowance (3×32kgs) than those in economy (2×23kgs), however it is impossible for us to second guess the actual luggage a passenger in any class will bring, so we believe the IATA standard is the most sensible option. Many of our upper class customers, are often on business trips and therefore bring far less than their allowance, similarly many of our economy passengers may use up their allowance easily on their two-week holiday. In putting this equation together we have consulted many sources of information, such as the Tufts report (4) and Climate Care’s report on calculating the environmental impacts of aviation emissions (5). In the Tufts report, they provide a table which compares the six different criteria which twelve different offset companies use. These are RFI, class of travel, additional variables (cargo in this instance), occupancy efficiency, flight distance and airplane type. We are utilizing four of these criteria in our equation, and we believe the last two are more effectively provided through our fuel uplift figures. The only other offset company who uses more criteria is Atmosfair and they have been criticized for being very expensive because they use all these different criteria. On review of this, we decided that whilst we wanted to be robust in our calculations we did not want to deter people at this delicate stage in the maturity of the offset market. We also consulted with organizations with expertise in this area, including myclimate and the Climate Group. We have had all of the data which feeds into this equation audited by CICS, who are an independent carbon verification agency.References
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