Safe Landing                            ZAS0039             

Written evidence from Safe Landing

Response from Safe Landing – a group of climate concerned workers in the aviation industry. As such all answers relate to aviation.

The most significant problem with relying on operational efficiencies to reduce emissions is the rebound effect. Increased efficiencies over the last 3 decades have resulted in reduced cost of air travel, making flying accessible to more people. This has resulted in growth in the sector, so total emissions have risen substantially, even as emissions per passenger have reduced. Without additional regulation there is no evidence that this trend will change.

Jet Zero scenarios are all based on substantial growth; from 273m passengers in 2018, to around 460m in 2050. This level of growth will exceed efficiency gains, therefore emissions will increase.

Furthermore, Jet Zero assumes a higher rate of annual efficiency gain (1.5-2%/year) than is supported by evidence. It also claims that “improving the efficiency of our current aviation system offers the best opportunities for short- to medium-term reductions in CO2 emissions.” This is not correct: measures to limit the growth of air traffic would be far more effective at ensuring short- to medium-term emissions reductions are achieved. We need to cut aviation emissions now to allow time for more efficient technology and measures to be developed and tested; and to learn the extent to which they can be deployed commercially and when. 

 

Para 2.3 of Jet Zero’s ‘Evidence and Analysis’ paper suggests:

 

“efficiency improvements such as these could reduce the fuel burn of aircraft coming into service in the mid-2040s by 40-50% compared to types entering service in the early 2000s.” 

 

However, aircraft entering service in 2045 will only account for a very low proportion of airlines’ fleets in 2050. Fleets will predominantly be composed of aircraft entering service in the 2020s and early 2030s, which will be aircraft designed in the 2010s. Research published in 2020 for the United Nations Environment Programme (UNEP) states (section 5.3.2):

 

“In general, there are likely to be improvements in aircraft airframes and engines in the next 20 or so years, which will improve the burn-fuel metric by around 1.2% per year. However, the crucial conclusion is that the sum of the potential improvements does not come near to matching the projected growth in aviation, let alone to reducing emissions from the current level”. 

 

It can be seen that the rate of efficiency improvement is slowing with time (see figure below).

Chart, line chart Description automatically generated

Figure: Long-haul aircraft fuel efficiency and global aviation emissions, historic and projected. From Peeters, P et al. (2016). Note: efficiency improvements are slowing and emissions are accelerating.  

  

Klöwer et al (2021), state:

 

“Planning on fuel efficiency improvements does not significantly reduce aviation’s contribution to warming, as past progress in efficiency was overcompensated by air traffic growth….” 

 

ICAO (2010) themselves agree that even:

 

“the aspirational goal of 2 per cent annual fuel efficiency improvement is unlikely to deliver the level of reduction necessary to stabilize and then reduce aviation’s absolute emissions contribution to climate change”

 

Despite claiming (in Annex A.9) that the “modelling also includes the positive rebound impact on demand due to efficiency improvements lowering the costs of flying” - this doesn’t appear to be the case, as Scenario 1 and 2 feature different efficiency assumptions but total passenger numbers and emissions (prior to abatement) remain unchanged. The Jet Zero team have confirmed to us by email that (despite the claim in Annex A.9) the rebound effect was not modelled in Scenario 2.

 

For these reasons, we disagree with the overall approach to rely on improving the efficiency of our existing system as a means to reach net zero by 2050.

 

In the Jet Zero Evidence and Analysis paper, Scenario 3 assumes 75% SAF uptake by 2050. Scenario 4 assumes 30% uptake. In the ‘Continuation of current trends’ scenario it will only reach 5% by 2050. 

 

Para 2.5 of the Evidence & Analysis paper accepts that “current SAF use in UK aviation is negligible and there is significant uncertainty around the availability and cost of SAF in the future.” 

 

In the ‘Letter on International Aviation and Shipping and Net Zero’ from Lord Deben of the Climate Change Committee to the UK Government (2019), he states that “Our scenario has a 10% uptake of sustainable fuels in 2050. It is not appropriate to plan for higher levels of uptake at this stage, given the range of competing potential uses for biomass across the economy… and uncertainty over which use will be most cost-effective”.

 

Potentially the largest issue facing ‘SAF’ is that no pathway has been commercialised that can produce fuel in significant quantities. The only pathway currently proven commercially is ‘HEFA’ produced from waste oils – however, the global supply of waste oil is severely limited and could, at best, only be scaled to supply a very limited % of current aviation fuel consumption. We therefore view it as a distraction.

 

In addition to volume resource constraints, there is competition with other sectors and waste oils are already utilised to produce road transport biofuels. The UK Government acknowledges within the SAF Consultation (Para 4.8) that:

 

“Relying on this fuel could also divert used cooking oil (the feedstock primarily used to produce HEFA) away from the renewable diesel (HVO) production process. When plants increase the product slate of HEFA over HVO, their overall fuel yield decreases and production costs increase. This means pivoting this feedstock away from use in road transport at this stage will make economy-wide decarbonisation more expensive”.

 

Therefore, this demonstrates that limited waste oil feedstocks are better utilised in the road transport sector on both an environmental and economic basis. Scaling aviation ‘HEFA’ would only result in shifting of emissions savings from one sector to another, whilst reducing total emissions saved, and increasing tax payer costs. 

 

We also recognise that policies favouring the diversion of waste oil feedstocks to air transport, are likely to make road and marine transport decarbonisation more difficult and expensive - which would increase costs for a wider section of society e.g. staple foods in supermarkets and is unlikely to be politically popular and sustainable.

 

As the SAF Consultation (Para 1.7) remarks, ‘SAF’ use “gives a route for existing oil refineries to transition towards more sustainable products, strengthening existing supply chains, building new ones and retaining the UK industry’s expertise and skills.”

 

For these reasons, we are concerned that the Jet Zero scenarios rely on HEFA scale-up, particularly in the near-term. Current and future cost projections for HEFA distract from the real costs and timescales of more scalable pathways.  It appears that government support may be directed towards prolonging fossil fuel industry assets or new facilities which may become stranded-assets once the reality of their sustainability credentials become more obvious.  As workers in the industry - we would prefer to see any government incentives directed towards other fuel pathways (where scalability and sustainability criteria can be met - e.g., e-fuels) and R&D support directed towards more efficient, radical aircraft designs that will be required given the higher fuel costs associated with these pathways.

 

Alternative fuels may contribute to reducing aviation emissions to some degree in the future but we need to cut aviation emissions now to allow time to assess the extent to which, and the timescale within which, they can be deployed commercially without damaging the rest of our economy.

 

There are three main types of ‘Sustainable’ aviation fuel: biofuel, synthetic fuel and green hydrogen. We will address the issues with each in turn:

 

    1. Biofuel

Global economies will need to use biomass for feeding a growing human population while also decarbonising the grid, domestic heating and ground transport. Aviation biofuels are not a sustainable or scalable solution without directly or in-directly causing increased energy-crop agriculture which leads to increased global food prices, water shortages, deforestation, drainage of peatland, loss of biodiversity and emissions from land-use changes which can be worse than fossil fuel. In other words, we need to use land for many other, critical purposes - there’s not enough land for everything. The future available quantity of sustainable biomass ‘waste’ is also strictly limited and should be considered a precious resource. 

 

It should also be noted that the Jet Zero definition of SAF (p26, ‘What is SAF’) includes list “Non-biogenic waste: e.g. unrecyclable plastics or waste fossil gases from industry” as SAF. These fuels are not sustainable. This approach would mean taking carbon stored in waste material and burning it, thus putting additional GHGs into the atmosphere. If there is plastic waste, it’s far better to leave it as plastic, with the carbon stored, than to burn it and release the carbon.

 

The 2020 UNEP report also warns: “Assuming that biofuel combustion is carbon neutral is ... a fundamental accounting error that rests on implicit spatiotemporal boundaries and assumptions…” and notes that “for many biofuels, the energy return on investment is comparatively low or possibly negative” (section 5.3.3). So, it is highly unlikely that biofuels can be scaled up to more than a small fraction of aviation fuel consumption by 2050 without damaging other sectors.
 

  1. Synthetic Electro-Fuels (e-fuels)

E-fuels are produced from electricity by synthesising hydrogen with carbon captured from the atmosphere to create a liquid hydrocarbon. They too face problems of scaling up, cost and the disproportionate use of renewable energy resources – i.e. there won’t be enough green electricity to meet all our other needs and also produce enough synfuels for an unconstrained increase in flying.

 

The inefficiency of the processes involved would require huge quantities of renewable energy. The electrical energy required to produce enough synfuel and hydrogen to meet the projected global annual aviation fuel consumption in 2050 would “triple to quintuple the renewable energy produced globally today” (EU, p. 44). Whilst renewable energy generation is growing every year, this electricity is also needed for decarbonising every other sector of the economy.

 

  1. Green Hydrogen

Jet Zero expects hydrogen “to play a key role in fuelling zero emission aircraft.” For hydrogen to be ‘green’, it must be produced using renewable electricity, which raises the same issue of availability – we will not have enough green electricity for everything we want: priorities have to be chosen. While green hydrogen offers some potential, there are significant costs and long timescales required to develop, test and deploy it, to make infrastructure changes at airports, to redesign aircraft to use and store hydrogen and to upgrade airlines’ fleets to replace fossil fuel powered aircraft. This means that it will not credibly support significant decarbonisation of aviation within the timescale needed.

 

As noted on p13 of Roland Berger’s 2020 report, ‘Hydrogen - A future fuel for aviation?’: “The main drawback of hydrogen is that, due to its low volumetric density, it requires four to five times the volume of conventional fuel to carry the same onboard energy.” The size, shape and weight requirements of fuel storage for commercial flying will require a major re-design of aircraft fuselages. Commercialisation and certification of new aircraft and engine designs can take more than 10 years and it takes much longer (20-30 years) for airlines to upgrade their fleets.

 

There are 2 options for zero emissions flight; electric and hydrogen. We do not believe that pursuing the development of zero emissions flight is a credible route to reducing GHG emissions to zero by 2050.

Electric: The 2020 UNEP report states that electric flight “will only slightly contribute to reductions in aviation sector emissions.” (Section 5.3.3). This is because batteries are simply too heavy for medium- and long-haul flights. Unlike burning liquid kerosene, the weight of batteries does not reduce as the journey progresses. Duncan Walker, Senior Lecturer in Applied Aerodynamics at Loughborough University, has calculated that the world’s largest passenger plane (Airbus A380) could only fly 1,000km with batteries versus its standard range of 15,000km: “To keep its current range, the plane would need batteries weighing 30 times more than its current fuel intake, meaning it would never get off the ground.” 

Hydrogen: see previous answer.

Jet Zero provides no evidence that these obstacles can be overcome.

We need to cut aviation emissions now to allow time for green hydrogen to be developed and tested; and to understand the extent to which, and the timescale within which, it can be deployed commercially.

 

The most effective way to maximise efficiency (i.e., reduce emissions intensity) is to constrain air traffic growth. This would have a number of benefits as it would ensure:

 

Another effective way to ensure efficiency improvements accelerate and aviation emissions reduce is to increase the price of aviation fossil fuel by introducing an appropriate level of fuel tax or an emissions price. An emissions price could factor in both CO2 and non-CO2 emissions and could also apply to alternative jet fuels (biofuels and e-fuels) which only partially reduce CO2 and non-CO2 emissions. This would send a price signal that incentivises manufacturers to accelerate technology development and consumers to alter their behaviour. Jet Zero appears only to use carbon pricing as a means to fund carbon offset schemes in the near-term and greenhouse gas removal technology in the long-term. This is inadequate to deal with the urgent need to cut emissions in the next 10 years. As the UK is no longer a member of the EU, the government is free to introduce an aviation fuel tax on domestic flights and flights to the EU immediately.

 

We advocate that the target should only be net zero if the use of carbon offsets to achieve this target is ruled out. We view carbon offset schemes as highly problematic due to the likelihood of issues such as verification, additionality and permanence. Greenhouse gas removal (GGR) technology is therefore far more likely to be required over carbon offset schemes. Resource (land, water, food, energy etc.) scarcity means that GGR must also be minimised and is likely to remain very high cost. As workers in the sector, we are concerned that leaders will bank on the use of cheap, ineffective offsets over the next two decades to “achieve” this 2040 target – when it appears highly likely that the use of such schemes will soon be discontinued. If they are relied on, then removed, the sector would be faced with unexpected high GGR costs that may cause a severe industry crash and loss of employment that could have been avoided through more robust forward planning.

In addition, a realistic tax / emissions price on aviation fossil fuel would make ‘SAF’ a more economically competitive fuel. This would incentivise all stakeholders to increase investment in technological innovation and would remove a significant barrier to uptake of SAF by operators i.e.: cost. The increased cost would be borne by consumers, adhering to the stated ‘polluter pays’ principle 

A price premium means introducing a carbon tax, at a realistic level, on aviation fossil fuels. Ideally this would be applied as an emissions price that accounts for both CO2 and non-CO2 impacts, as a potential benefit of alternative fuels is the ability to partially reduce both CO2 and non-CO2 emissions. Clarity (currently lacking) on the relative pricing of all emissions would be of great benefit for the industry to plan and select the most appropriate technology strategies.

Fuel tax (emissions pricing) is essential, with a frequent flyer levy on top to place the bulk of increased financial burden on to frequent flyers who are predominantly from high-income and high emissions groups.

Discuss international aviation emissions at COP26.

CORSIA will be ineffective as the most emissions are exempt and the price of emissions will fall within the uncertainty of existing fuel price fluctuations. CORSIA needs to be replaced or drastically reformed to change this.

September 2021