June 17, 2019
On 12th June Theresa May committed the UK to net zero emissions by 2050. With aviation representing the hardest sector to decarbonise, what will this mean for how – and how much – we fly in future?
No radical technical solutions available today are likely to be able meet the scale of the challenge on their own. A combination of solutions, including technology, cultural shift, and active demand constraint, will all need to be part of the picture and any emissions that remain will need to be balanced by carbon removals. The Government wants to keep its options open when it comes to international offsets, though it says it intends to reach the net zero target domestically, as the CCC has recommended.
The CCC’s modelling for net zero ramps up the assumed pace of technology improvements to the max, including more efficient versions of conventional jet engines (e.g. ultra-high bypass ratio turbofans), use of hybrid-electric engines, and use of composite materials and high-aspect ratio wings in aircraft design. Electric planes would represent a step change in technology, but it is unlikely that we will see a fully electric commercial airline before 2050 – in other words, too late to help with the net zero target. The long lifetimes of aircraft also present a barrier: a conventional plane that rolls off the production line today is very likely to still be flying in 2050.
Sustainable biomass could be used to produce low-carbon fuels in future, but this will be limited in supply and can be more efficiently used in other sectors where it can be combined with carbon capture and storage (CCS), CCC has advised. This is because for industries that are on the ground, carbon can be directly captured after the fuel is burnt, whereas for aviation fuel, CCS can only be used at the fuel production stage. This is likely to limit the application of sustainable biomass to about 10% of total aviation fuel demand in 2050, says the CCC.
Synthetic fuels, using renewable energy to generate liquids are technically possible to produce, but are likely to be very expensive and would require CO2 to be captured upfront for their production.
Taking into account maximum feasible technology and improvements, aviation emissions could still be as high as 31MtC02 according to CCC’s modelling or even higher according to Government’s latest forecasts, even if passenger demand growth is limited. These residual emissions will need to be balanced by carbon removals to avoid aviation busting the net zero target.
CCC advocates for the aviation industry to lead the way in carbon removal technologies. This may not come cheaply, though it’s hard to know exactly what the costs will look like at the moment since technologies like Direct Air Capture (a form of carbon removal) are not well developed. How these costs are passed on to consumers will depend partly on whether airlines have to make the investment directly or if the Government does so on their behalf.
Limits on passenger demand will have to be part of the picture in order to meet net zero by 2050. It’s likely that alongside government policy, we will need to see shifts in public behaviour. We are beginning to see development in this area, particularly in Sweden, where the flygskam (or flight shame) movement has started to shift attitudes about leisure flying (air traffic in Sweden was down by 5% and train passengers up by 8% the first quarter of this year). We hope to see similar shifts in the business community, particularly as organisations such as CBI have come out strongly in support of the UK’s net zero commitment.