Sustainable fuels are produced using renewable or recycled waste carbon meaning that British Airways displaces a litre of conventional jet fuel for every litre of SAF that it consumes. SAF has been shown to provide significant reductions in overall CO2 lifecycle emissions compared to fossil fuels, and for waste-derived fuels these can be more than 80%. Furthermore, SAF contains fewer impurities (such as sulphur), so it has lower air quality impacts than conventional jet fuel. Most of the SAF in production at the moment are based on waste oils and fats. British Airways is working on new supply chains using municipal waste that it hopes will be commercially available within the next 2 years.

The CO2 emissions associated with the SAF you purchase will be allocated only to you and this will be audited for British Airways by an independent assurance company.

We ensure that the SAF supplied has been through a detailed sustainability assessment using recognised sustainability certification systems. These assessment systems are independently verified and ensure that the fuel has genuinely been derived from waste-based sources. The certification process also ensures that the whole life cycle greenhouse gas emissions are accurately calculated and that systems are in place to minimise the impact of producing the fuel.

SAF is not presently produced in large volumes and many technologies are still under development, so the production costs are much higher than for conventional jet fuel. British Airways and its parent International Airlines Group are investing $865m over the next 20 years to help development of this important industry. By selecting to purchase SAF, you are helping to accelerate the development of this new sustainable avenue for aviation.

Today, nature-based solutions that remove carbon are often verified by the same certification standards that verify other carbon offsets, and so if you are focused on removals, you need to independently confirm that they are removing carbon as opposed to reducing or avoiding it. Other forms of carbon removals are often verified by different certification standards (like Puro.Earth).

Key criteria that determine the quality of a credit include:

• Real – The offsets are tangible and measurable

• Additionality – The emissions reduction would not have occurred in the absence of the project.

• Permanence – The project delivers the claimed emissions reductions in a sustained manner over time.

• No Leakage – The emissions reduction achieved with the project does not lead to an increase in emissions elsewhere.

• Retired permanently – Following the sale of the carbon credit, it is permanently removed from the market mechanism, ensuring that the offsets there is no double counting or double selling.

• Verifiability – A robust audit trail demonstrating the project’s goals and its delivery against those goals.

The price of a carbon credit depends on many factors, including supply and demand in the market and the quality, type, size, and geographical location of the project and the credit age (vintage) – but most importantly, the value that credit creates.

The availability of credits will change depending on supply and demand factors as well.

Cost per tonne and cost per mile may vary depending on:

The project you select – projects vary in price, as described above.

Emissions factors – see FAQ about emission factors.

The carbon credits we are offering vary in price from approximately £8.00-£11.00 per tonne and carbon removal credits vary from £30 - £100 per tonne.

Each project has a different price depending on technology, location, carbon standard etc.

We combine the data that you enter with data from the airline to calculate your emissions. If your flight is within Europe, we adjust the emissions calculation to reflect the emissions already reduced by British Airways’ participation in regulatory systems including the UK and EU Emissions Trading Systems so that we aren’t double counting these emissions.

Our calculator uses average historical British Airways data from the most recent full year. If your flight is within Europe, we adjust the emissions calculation to reflect the emissions already reduced by British Airways’ participation in regulatory systems including the UK and EU Emissions Trading Systems so that we aren’t double counting these emissions.

Other calculators may use factors that are specific to a particular airline, or standard government factors. Other reasons for differences include the extent to which data is split by cabin class and whether non-CO2 effects are included. Given that the relative scale of non-CO2 impact is uncertain and subject to ongoing research, we are using a radiative forcing index of 1. This will be reviewed when further information becomes available.

This is up to you. Emissions are based on the number of passengers using a seat on the aircraft. If your child is old enough to sit on their own in a seat, then you can offset for them. If they are a baby in arms, then no action is needed.

CHOOOSE and British Airways are working towards enabling you purchase climate products during your booking process as soon as possible. We have chosen to offer customers the opportunity to act on their footprint now rather than wait for changes to booking systems.

The data in the calculator is updated regularly based on:

• Annual emissions factor data provided by British Airways.
• Changes to emissions regimes.

Aircraft engines burn fuel in order to transport passengers from one place to another. This process creates CO2 and other emissions.

These total emissions are divided among passengers, taking into account the fact that passengers in business and first class have larger seat room and increased luggage allowances.

The factors that determine the emissions for a journey are:

•Arrival and departure point – this determines distance and fuel consumption

•Number of passengers

•Travel class

•Carbon emission factor – this determines the CO2 equivalent per kilometre

•Load Factor

The UK and EU Emissions Trading Systems (ETS) work by setting a limit (or cap) on the amount of CO2 emissions that are allowed from obligated industries e.g. power generation, aviation, fuels and chemicals production. Companies are required to reduce their emissions or buy emission reduction credits from other companies in the system that have reduced their emissions and thereby have allowances to sell. CO2 allowance units equal to the cap are distributed by governments to airlines either freely or through auctions. Airlines that emit CO2 above their cap must buy emission reduction units from other companies that have reduced their emissions below their cap and thereby have allowance units to sell.

British Airways calculates its individual ETS cap and which of its emissions are already accounted for through the ETS. ETS CO2 allowance units purchased by British Airways above its individual cap are treated as emissions reductions achieved through emissions trading. To address your flight emissions, for flights regulated by emissions trading, we subtract the CO2 allowance units above British Airways' individual emissions cap that the airline has paid for through the ETS to leave the remaining residual CO2 emissions that need to be addressed.

In addition to greenhouse gas emissions including CO2, aircraft also cause non-CO2 climate effects such as condensation trails. Research into these effects and the appropriate metrics to characterise them continues. Radiative forcing is a metric or measurement basis that aims to combine the CO2 and non-CO2 climate effects. Given that the relative scale of impact is uncertain and subject to ongoing research, we are using a radiative forcing index of 1. This will be reviewed when further information becomes available.