Written evidence submitted by ZeroAvia (HCC0037)

ZeroAvia is pleased to respond to the Scottish Affairs Committee’s inquiry into hydrogen and carbon capture in Scotland.

We are a UK business that is pioneering zero-emission, hydrogen-electric engine technology for aviation. Based in Kemble, England, we are partnered with some of the most forward-thinking aviation and R&D companies in Scotland to advance our zero-emission flight capabilities, including joint R&D undertakings with the European Marine Energy Centre in Orkney, Loganair, Highlands and Islands Airports Limited and Edinburgh Napier University.

As a hydrogen-electric aviation company, we have focused our response to this inquiry on the relationship between hydrogen-electric aviation and developing the hydrogen economy in Scotland. Our key recommendations to the Committee are as follows:

●        Hydrogen-electric aviation is the only technology that is capable of delivering truly zero-emission flight at scale prior to 2050. From 2024, UK-led hydrogen-electric technologies will begin to eliminate in-flight climate impacts. The Scottish Government should work with the UK Government to identify and back the right solutions by investigating the full climate change impacts of alternative fuels such as Sustainable Aviation Fuels (SAFs) - including non-CO2 impacts which are now commonly understood to be at least as harmful as CO2 emissions alone -  and analysing the viability and cost implications of all decarbonisation solutions. Measures to promote adoption of  SAFs in the short term are appropriate, but we would encourage the Committee to recommend that the UK and Scottish Government ensure adequate support for the transition to truly zero emission solutions, like hydrogen electric aviation, in the mid (next five years) to long-term. The technology pathways indicate that these solutions will be capable of addressing the domestic aviation sector’s needs comfortably over the next 10 to 15 years, and will have the dual benefit of turbocharging the hydrogen economy in Scotland.

●        Scotland has the potential to be an early leader in hydrogen-electric aviation. Scotland has significant advantages that it can leverage in the pathway to truly zero emission aviation given its natural strengths and skills in renewable power and maintenance, repair and overhaul (MRO) in aviation. The Scottish Government and UK Government should collaborate with regulators and industry to drive adoption, investment and innovation in hydrogen-electric aviation. This includes adopting a coordinated pathway on hydrogen infrastructure ahead of 2024 when airline operators will require the introduction of hydrogen fuelling infrastructure at airport sites, and enable widespread domestic and early international hydrogen aviation flights to be delivered by the end of the next Parliament.

●        Aviation plays a critical role in the UK’s national prosperity. The Union Connectivity Review made clear that the UK’s airports act as hubs for many communities across the UK, including remote communities in Scotland and are focal points for personal mobility, logistics, and employment. However, without intervention, aviation and airports will occupy an ever-increasing proportion of both the UK and global carbon emissions as other sectors decarbonise faster. Through investment, research, development and manufacturing, the UK has the potential to be an early mover in a market valued in the billions that will lead to global exports. An ambitious mandate for zero-emission domestic aviation is a rare win-win, and the prospect of mandates for zero-emission/low carbon aircraft for Public Service Operation routes was actively raised in the Union Connectivity Review. It is a chance to deliver crucial environmental objectives while seizing an advanced industrial opportunity to support future prosperity.

About ZeroAvia

In 2020, at Cranfield Airport we successfully conducted the world's first ever hydrogen fuel-cell powered fully electric flight of a commercial grade aircraft under the HyFlyer project, with support from the UK Government through the Aerospace Technology Institute (ATI) programme. We are currently working to scale up the technology through the HyFlyer II programme, which will see the development of a certifiable hydrogen-electric powertrain that can power airframes carrying up to 19 passengers. Commercial hydrogen-electric flights are planned to begin from 2024 onwards with a range of 300 nautical miles, equivalent to a journey from London to Edinburgh or Glasgow.

ZeroAvia is aiming to offer zero-emission powertrains to increasingly larger aircraft with longer potential range - targeting 50 - 80 seat aircraft with 1,000 nautical mile (nm) range by 2026, right through to 200+ seats with a 5,000nm range by 2040.

Passengers could fly without any greenhouse gas emissions from Edinburgh to Rome before the end of the decade, and from Glasgow to Los Angeles within 20 years. Over 400 engines are under pre-order.

Why hydrogen-electric aviation?

We believe hydrogen-electric aviation, powered by green hydrogen, is the only practical pathway to truly zero-emission flight, and other technologies currently being explored fail to offer the same transformative potential.

SAFs are often presented as the solution to tackling aviation’s climate change impact. But they are expensive, difficult to scale and produce harmful non-CO2 emissions including nitrogen oxides(NOX)), sulphur oxides (SOX), soot and high-temperature water vapour. Research suggests that the non-CO2 emissions impacts of aviation at altitude are at least as harmful as CO2 emissions alone (see EASA report), and likely more so.

Even when it comes to carbon emissions, however, reductions through SAFs are  unlikely to keep pace with increasing emissions through growing demand. In a study published in June 2020, Clean Sky, the largest European research programme, estimates that SAFs can reduce carbon emissions by just 30%-60%. The study’s authors believe that hydrogen fuel cell (also known as hydrogen-electric) systems have the potential to reduce climate impact by 75 to 90 percent.

Just like an electric car, an electric plane uses electricity to create motion by using an electric motor, instead of burning fossil fuels to power the vehicle. Unlike cars, electric planes carrying a number of passengers over long distances are not practical with batteries which are too heavy in proportion to the amount of energy they can carry. This is not just the consequence of the current technology limitations, but is rooted in some theoretical limitations of how much energy a lithium ion battery can carry, for example. Battery cycling costs would also be prohibitive from a maintenance cost point of view for airline operators.

The hydrogen-electric approach, however, uses hydrogen fuel cells, instead of a battery, to create electricity to power the motors. A hydrogen-electric plane does not burn any fossil fuel. Instead, a catalytic electro-chemical reaction in the fuel cell creates electricity to power the motors. Because no fuel is burned, there are no climate harming emissions - no CO2, no NOX, no SOX, no particles, and the water vapour emissions can be very effectively managed due to a much lower vapour temperature and rate of exhaust compared to any combustion technology. Hydrogen to fuel aircraft can be created on the ground by splitting water (H2O) into hydrogen and oxygen using electricity to power an electrolyser. If the electricity used here is generated through zero-emission sources like solar or wind, the fuel itself can be created with zero-emissions as well.

The high potential of hydrogen as the optimal future fuel for aviation was identified by the UK’s world-leading Aerospace Technology Institute (see report on FlyZero fuels).

Hydrogen-electric aviation will also create the demand needed to scale up hydrogen production in Scotland and the UK, which is vital to the immediate and longer term success of our hydrogen economy, and would have the dual benefit of establishing hydrogen hubs at airports. Hydrogen delivered at scale is likely to deliver favourable economics for operators, improving the viability of a sector that is of strategic importance, including for delivering on the aims of the Union Connectivity Review (see report by European Regions Airlines Association).

How can the Scottish aviation industry become a world leader in hydrogen electric aviation?

The Scottish aviation industry can become a world leader in hydrogen-electric aviation through sustained investment in R&D; creating incentives for airlines to adopt hydrogen-electric aviation; support for hydrogen production and refuelling in and around airports and; supporting regulation and operating environments to develop at pace.

●        R&D: While the majority of R&D funding will come through the UK Government and UKRI, Innovate UK and the ATI, it would be worthwhile for the Committee to consider how this can be directed to support further research in Scotland into hydrogen production and management in an "airport hub" context and also into zero-emission propulsion technologies themselves.

●        Incentives for airlines: Transport Scotland and the Scottish Government should support innovative routes between international destinations with close proximity over the short-term in order to expedite adoption of zero-emission flight technologies that can then lower operating costs. Collaboration with governments and the aviation industry in the Republic of Ireland, Germany, Benelux and the Nordics regions, for example, on the establishment of new, zero-emission trial routes would help increase tourism and trade from closely neighbouring countries.

●        Infrastructure: While support for the fundamental propulsion technologies is vital, it is also crucial that Scotland targets availability and regulation of zero-emissions infrastructure for airports and aviation. This will require funding for innovation and trial activities to match timelines for the commercialisation of zero-emissions propulsion systems. When ZeroAvia commercialises its 19-seat hydrogen-electric powertrain in 2024, operators must be empowered to put it into use quickly to ensure we maximise its environmental and societal benefits.

●        Support for hydrogen production: The Scottish Government’s draft Hydrogen Action Plan commits over £100 million to the development of the hydrogen economy over the next five years. It also recommends the creation of Regional Hydrogen Energy Hubs. ZeroAvia supports this ambition and recommends that airports should be prioritised as a critical use case here, given the potential to decarbonise ground operations, onward transport links and proximate industry using the green hydrogen produced at or nearby airports.

●        Operating environments and regulation: New technologies need to be certified swiftly and effectively, and R&D programmes need to be supported to proceed at pace. We therefore recommend that the Committee encourages the UK Department for Transport to expand the specific and funded support available at the Civil Aviation Authority to ensure that new zero emission aviation programmes can be fast tracked while maintaining the outstanding safety and regulatory standards the aerospace sector depends on. The relatively low costs of action here significantly outweigh the societal and economic impacts of slow progress in achieving certification for new technologies.

What infrastructure, and investment in infrastructure, is needed for green hydrogen to be easily available for heavy transport across the whole of Scotland?

According to ZeroAvia’s technology roadmap, truly zero-emission hydrogen-electric aircraft will be capable of powering nearly all domestic take-offs before 2040. From 2024 onwards, ZeroAvia will deliver HyFlyer II, a zero-emission hydrogen-electric powertrain for aircraft of up to 19-seats. This programme is commencing its first flights this year, and will be fully certified for market entry with early-adopting operators, including UK domestic airlines. From 2026, ZeroAvia will deliver certified hydrogen-electric powertrains for operators powering regional aircraft of over 50 seats, capable of flying up to 1,000NM. 

This means that from 2024 onwards, airline operators will require the introduction of hydrogen fuelling infrastructure at airport sites, with the ability to supply increasing volumes of hydrogen to increasing numbers of aircraft. According to our calculations, we estimate that to repower domestic UK flights with hydrogen-electric propulsion Edinburgh and Glasgow Airports would require 20 tonnes and 15 tonnes of hydrogen per day respectively, Aberdeen would require 8 tonnes. This large stable demand would encourage and necessitate domestic hydrogen production and meet Scottish Government targets, which are linked to the growth of a wider hydrogen economy, with associated industry, employment and prosperity.

While the UK and Scottish Governments are investing in the scale-up of low-carbon hydrogen, significant challenges remain around distribution. As aviation emerges as one of the key consumers of hydrogen, hydrogen should therefore be generated, stored, and supplied near to airports and the aircraft that will utilise it. This would have the dual benefit of providing security of supply and minimising the costs and complications associated with distribution, while establishing hydrogen hubs - where airports act as focal points for other hydrogen use cases -  such as public transport fleets, HGVs and freight, ground operations and proximate industrial uses.

As stated above, we therefore welcome the recommendation in the Scottish Government’s Hydrogen Action Plan to create regional hydrogen energy hubs with multiple end-users across multiple sectors and believe airports should be prioritised as a critical use case here. For example, a hydrogen bus fleet is already in operation in Aberdeen, and will soon be rolled out in Glasgow. Establishing regional hydrogen hubs at the airports in these locations would be a natural integration between different hydrogen use cases, combining supply and demand, and making efficient use of vital hydrogen infrastructure.

The ATI jointly with the Airports Council International (ACI) has published research which finds that hydrogen generation for airports would be best undertaken on-site and, at scale, and would likely involve dedicated electrolysis and piped transmission around the airport site. In the interim, as airports scale up their use of hydrogen, it also highlights that airports can invest in mobile truck-based models that combine electrolysis, storage and fuelling equipment.[1]

The technologies to do this - low carbon electrolysis, compression, tank-based storage, and fuelling equipment – exist, are commercialised and are rapidly improving in response to increasing investment in the sector. ZeroAvia as part of the HyFlyer I project used the sub-scale Hydrogen Airport Refuelling Ecosystem (HARE) system to fuel its aircraft using hydrogen generated on-site, compressed and stored for use, and provided via a mobile refuelling unit.

However, there are significant gaps in the technologies, knowledge and regulatory approaches that are needed to successfully deliver hydrogen as an aviation fuel and introduce hydrogen aviation into the marketplace, particularly around liquid hydrogen which will be necessary to fuel aircraft above around 40 seats (due to the volumetric constraints of gaseous hydrogen). With support from the Department for Transport and Connected Places Catapult’s Zero-Emission Flight Infrastructure programme, this is something ZeroAvia is researching as part of its LHARE project.

In addition to this successful but to-date small programme, we recommend that Transport Scotland work with the Department for Transport, and other relevant agencies to:

●        Remove the barriers (no proven scalable technology configuration, lack of best practice and management of hydrogen at airports and no standards for the regulation of hydrogen at airports including generation, storage and supply) preventing airports from investing in and then commercially delivering hydrogen as a fuel for hydrogen-powered aircraft. This could be achieved by increased research powered by an extension of the ZEFI scheme.

●        Establish the world’s first Hydrogen Airports Network - a distributed UK-wide network of hydrogen-enabled airports that are home to established supply technologies, supported by managerial and operational best practice, and operating under safe and permitted regulatory rules. Given Scotland’s Highlands and Islands connectivity needs, it provides a great use case for such an airport network and the early establishment of demonstration routes.

●        Collaborate with colleagues in the Department for Business, Energy and Industrial Strategy working on the Hydrogen Business Models and Net Zero Hydrogen Fund to ensure a ‘supply and demand’ approach is taken to developing the production and supply of hydrogen, with the increasing demand in transport for hydrogen vehicles. This joined-up approach will be essential if there is to be enough hydrogen available to power commercial, domestic flights from 2024, and to unlock the wider potential of airports to act as  hydrogen transport hubs for buses, trains, taxis and more.

These steps would ensure that there is a coordinated pathway across Scotland and the UK  - in conjunction with industry -  that achieves successful adoption of hydrogen supply in time for adoption of hydrogen-electric aircraft.

Which market mechanism should be used to incentivise investment in producing low-cost green hydrogen?

Producing low-cost green hydrogen requires supply and demand to develop in parallel. As stated above, we estimate that to repower domestic UK flights with hydrogen-electric propulsion, Edinburgh and Glasgow Airports would require 20t and 15t of hydrogen per day, providing a steady demand case for green hydrogen production. This stable demand would encourage and necessitate domestic hydrogen production and meet Scottish Government targets, which are linked to the growth of a wider hydrogen economy, with associated industry, employment and prosperity.

We also urge the Committee to consider the interplay between the Renewable Transport Fuel Obligation (RTFO) and SAF Mandate to unlock investment in green hydrogen production and hydrogen-electric aviation.

Confirming the modernisation of the RTFO is an essential step as it is currently the only available measure to provide financial support for producers of hydrogen for transport. The Department for Transport is also concurrently working through the response to its SAF Mandate consultation (due late Spring) and, for many of the reasons outlined above around the relative environmental impacts of SAF vs. hydrogen-aviation, it is essential that a system does not arise that provides preferential or equal incentives to SAFs over green hydrogen consumption when hydrogen-electric technology is certified and ready for market adoption. We are concerned that a situation could arise where climate impacting technology is better incentivised than true zero-emission technology. 

We therefore welcome the Scottish Government’s commitment to engage with Westminster to reform the RTFO, and we encourage the Scottish Affairs Committee to recommend that the Department for Transport acts urgently on this issue.

What training is required to build a hydrogen-ready workforce in Scotland?

Scotland has tremendous advantages that it can leverage in the pathway to sustainable aviation given the natural strengths and developed skills in both

renewable power and maintenance, repair and overhaul (MRO) in aviation.

As above, we estimate that to repower domestic UK flights with hydrogen-electric propulsion, Edinburgh and Glasgow Airports would require 20t and 15t of hydrogen per day, providing a steady demand case for green hydrogen production leveraging Scotland’s expert capabilities and infrastructure in renewable power generation, with the potential to create significant jobs in the renewables industry.

Turning to the opportunities presented in terms of jobs in MRO, ZeroAvia has been looking closely at its go-to-market model for our first powertrain products - ZA600 by 2024 (capable of powering 10-20 seat aircraft) and ZA2000 by 2026 (capable of powering up to 90 seat aircraft) and is investigating establishing retrofitting and maintenance hubs alongside airline operator and OEM partners. There will be an enormous advantage for countries that nurture skills in new, zero-emission propulsion technologies, with hydrogen-electric the most likely technology to succeed long-term.

ZeroAvia is at the intersection of the key strengths required to leverage this opportunity - aerospace engineering and hydrogen, but this intersection is a

novel area, and talent is hard to find. One of the key reasons ZeroAvia chose to locate the majority of its R&D in the UK was access to the significant pool of aerospace engineering talent. We are also cognisant of the significant talent in aerospace across the breadth of Scotland, particularly across the central belt.

We are already working with a number of leading universities on skills development, and we would like to collaborate with the Scottish Government on how to make this area of engineering unparalleled globally.

March 2022

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