For your calculations, flight emissions factors are used from the UK Government GHG Conversion Factors for Company Reporting 2019 version (known as DEFRA 2019). This methodology has been selected due to the global nature of operations and emissions sources. It is widely recognised as the most accurate and comprehensive methodology, and includes important emissions criteria such as Well-to-Tank^ and Radiative Forcing^^ which aren’t included in some other standards.
Other emissions factor methodologies can be utilised in the BlueHalo™ product suite including those from government agencies in Australia, New Zealand, the United States and the European Union. For more information on BlueHalo™, see here.
^Well-to-Tank (WtT) emissions include the CO2 generated during the production of the fuel, its transportation to the fuel station and dispensing to the vehicle tank.
^^Radiative Forcing (RF) is the impact on the overall energy balance of the planet –caused by non-CO2 warming pollutants, such as water vapour, aerosols and nitrogen oxides emitted by aircraft at high altitude.
Accommodation factors have been produced from a global database of over 3,000 hotels across the globe leveraging the Cornell Hotel Sustainability Benchmarking Index which is widely recognised as the global best practice for estimating carbon, water and energy. BlueHalo™ has matched the most granular data available for each location. BlueHalo™ has also in most cases identified the class of hotel (1-5 star) and applied the appropriate emissions factors.