Project Acorn is the first airside hydrogen refuelling trial ever to take place at a major UK airport
Hydrogen has been used to refuel and power critical parts of easyJet’s ground operation at Bristol Airport, demonstrating hydrogen can be safely and reliably used in place of other fuels in an airport
The data and insight gathered will be used to create the first ever safety guidance and inform the creation of the regulatory framework
Critically, the UK Civil Aviation Authority (CAA) has played an active role in the trial as an independent reviewer of the safety case
The trial also aims to accelerate the use of hydrogen in aviation and across other industries
A ground-breaking airside hydrogen refuelling trial, led by easyJet and supported by several cross-industry partners, has been successfully completed at Bristol Airport – the first airport trial of its kind at a major UK airport.
Hydrogen was used to refuel and power ground support equipment (GSE) – specifically, baggage tractors – servicing easyJet passenger aircraft. Conducted as part of the airline’s daily operations, the trial demonstrates that the gas can be safely and reliably used to refuel ground equipment in the busy, live airport environment.
The trial, dubbed Project Acorn, was in development for over a year and involved many other leading organisations from across aviation, engineering, logistics and academia. These include Cranfield Aerospace Solutions, Cranfield University, Connected Places Catapult (CPC), DHL Supply Chain, Fuel Cell Systems, the IAAPS research institute, Jacobs, Mulag and TCR.
The group intends to use the outputs of the trial to help develop industry best practice standards, provide guidance to airports, airlines, local authorities and regulators on required infrastructure changes, and support the development of a regulatory framework for hydrogen’s use on an airfield – standards which, due to hydrogen’s nascency in aviation, do not currently exist.
The data and insights gathered will also feed into research that groups like Hydrogen in Aviation (HIA)* are conducting to ensure UK infrastructure, regulatory and policy changes keep pace with the technological developments in carbon-emission free flying. It also supports the work and ambitions of other bodies such as Hydrogen South West (HSW) and the Hydrogen Innovation Initiative (HII), the latter having also co-funded the project.
David Morgan, Chief Operating Officer at easyJet, said: “It’s without doubt that hydrogen will be an important fuel of the future for short-haul aviation, as demonstrated by the rate of innovation we’re seeing.
“While the technology is advancing at an exciting pace, as hydrogen isn’t used in commercial aviation today, there is currently no regulatory guidance in place on how it can and should be used, and so trials like this are very important in building the safety case and providing critical data and insight to inform the development of the industry’s first regulatory framework. This will ensure regulation not only keeps pace with innovation, but importantly also supports the industry in meeting its decarbonisation targets by 2050.”
Tim Johnson, Director for Strategy, Policy and Communications at the Civil Aviation Authority, comments: “Projects such as this are cornerstones of our commitment to support innovation and decarbonisation in the industry.
“This trial will serve as the basis of a White Paper which we will also be contributing to, as well as allow for the creation of further safety guidance and regulatory standards for the use of hydrogen in aviation.
“We look forward to helping nurture this seed of the future greener aviation sector as it continues to grow.”
Anthony Browne, Aviation Minister, comments: “Project Acorn is a great example of the UK aviation sector pushing the boundaries of what’s possible - using leading engineering to make decarbonisation a reality from the ground operation to the planes themselves.
“Innovative projects like this are crucial to achieving our target, set out in the Jet Zero Strategy of zero emission airport operations by 2040.”
Project Acorn - the seed to more rapid hydrogen growth in the UK:
There is a compressed time window for the UK’s aviation industry to develop the ground infrastructure, safety standards (including how to use, control and transport hydrogen) and operational procedures needed to make the sector’s operations hydrogen-ready.
Project Acorn is designed to be a first step on this journey, with limited trials of GSE equipment accomplishing a key objective of receiving clearance for airside refuelling from the Civil Aviation Authority (CAA) – the regulator playing an active role in the trial as an independent reviewer of the safety case.
The safety assessments and emergency planning with local authorities that serve Bristol Airport will also provide invaluable learnings for future developments and serve as a blueprint for other local authorities – providing them with the necessary skills and resources to assist airports in making the transition to hydrogen.
A shorter-term objective for this project is to lead to the long-term or permanent deployment of hydrogen GSE at Bristol Airport and readying the airport for trials and then commercial operations of hydrogen-fuelled aircraft.
Developing the safety case and regulatory framework to accelerate hydrogen in aviation:
Another objective of the trial is to develop the safety and regulatory framework needed to accelerate hydrogen in aviation.
While hydrogen is a potential zero carbon emission fuel source for aviation and important developments have already been made across the industry**, there remains significant regulatory, safety and certification challenges. More research and testing is therefore required to inform hydrogen infrastructure policy and safe handling in airport and airline operations to support future hydrogen adoption.
Project Acorn’s operational trial of gaseous hydrogen-fuelled GSE in an airport environment represents one such opportunity and, as the first airside hydrogen refuelling trial to take place at a major UK airport, it is a significant milestone and an important stepping stone in future developments for hydrogen’s use in aviation.
The ultimate aim of this research is to support the wider decarbonisation of aviation through more rapid uptake of hydrogen.
A step-by-step guide to the key stages of the trial:
Safety & Evaluation: Landside operational trials and training were conducted in a safe and controlled environment at Cranfield University in the weeks prior to the test at Bristol airport.
Storing and distributing the hydrogen: Tanks containing hydrogen (H2) and a hyQube hydrogen refueller, designed and provided by Fuel Cell Systems Ltd, were transported to the Project Acorn trial site at Bristol Airport. In terms of how the process works --
The hyQube acts as the ‘fuel pump’ to pump hydrogen from the H2 cylinders into the empty tanks of the baggage tractor – the end use for the hydrogen.
The hyQube dispenses hydrogen through an attached nozzle exactly like refuelling a car at the petrol station. Although unlike refuelling a car, the nozzle doesn’t have to be held during fuelling as a complete seal is formed when the refueller is connected to the baggage tractor
The hyQube dispenses the hydrogen gas from the H2 cylinders into the tanks onboard the Mulag baggage tractor with just the press of a button
Once the tanks reach the full pressure of 350bar – indicating the vehicle is fully fuelled – the hyQube automatically shuts off, the operator disconnects and the vehicle is ready to go!
It takes approximately 3 minutes to fill up a full tank on the baggage tractor and this will keep it running for 2-3 hours before needing more fuel
End use (powering the tractor): The GH2 baggage tractor (manufactured and factory tested by Mulag and fitted with a Globe FC proton-exchange membrane fuel cell) was refuelled by trained DHL personnel via the mobile refueller at Bristol Airport. DHL’s personnel operated the GH2 baggae tractorto service easyJet aircraft turnarounds at a remote stand at Bristol Airport, which towed passenger luggage from easyJet passenger aircraft to and from the plane and airport as part of a normal operation.
The many benefits of hydrogen in aviation:
Many leading experts believe hydrogen powered aviation will not only be pivotal in delivering net zero, but it will bring many economic benefits too.
The Department for Transport’s Jet Zero Strategy*** estimates that rapid investment in hydrogen aviation could provide upwards of 60,000 new jobs across the UK, with Hydrogen UK projecting that hydrogen could contribute £18bn GVA and help meet up to 50% of the UK’s energy requirements by 2050.
Green hydrogen, produced from renewables, is a particularly exciting alternative aircraft fuel as, unlike other alternatives, it produces no carbon emissions. If fully realised, it will aid significantly with the industry’s decarbonisation goals, while helping preserve an industry that provides significant value to our economy – UK aviation employs 230,000 people and contributes more than £22bn directly to GDP per year, plus £34bn from exporting aerospace components.
The Jet Zero Council has projected in the strategy that rapid investment in hydrogen aviation could see the UK securing up to 19% global aerospace industry and share of a benefit valued at £178bn per annum in 2050, which means this could generate an additional £34bn per annum for the UK.
Investing in hydrogen will also help to preserve the social benefits of flying, continuing to connect people to business, loved ones and new destinations.
ENDS
Notes to Editor:
References:
*Hydrogen in Aviation (HIA) is formed of easyJet, Rolls-Royce, Airbus, Ørsted, GKN Aerospace and Bristol Airport.
**Airbus announced its ZEROe project and the ambition to bring the world’s first hydrogen-powered aircraft to market by 2035, and Rolls-Royce and easyJet’s partnership to develop hydrogen-powered engine technology continues to go from strength to strength.
*** Department for Transport’s Jet Zero Strategy
Additional quotes from Project Acorn partners:
Cranfield University - Dr Thomas Budd, Senior Lecturer and DARTeC Fellow in Airport Planning and Management at Cranfield University commented: “Decarbonising airport ground operations using hydrogen fuelled GSE represents an important opportunity for the industry; both to help cut emissions in the short-term and to lay the foundations for scaling up operations for refuelling hydrogen aircraft in the future. There is still much that needs to be done to make zero emissions flight a reality, but projects like this help demonstrate to Government, industry, and the travelling public that we can use hydrogen safely and efficiently in an operational airport environment. We are happy to support the Acorn team by utilising our expertise in zero emissions airport infrastructure, operations and safety, as well as the cutting-edge hydrogen refuelling and testing facilities we have at Cranfield.”
Connected Places Catapult (CPC) - Andrew Chadwick, Interim Ecosystem Director - Aviation and Airports, Connected Places Catapult, commented: “We're delighted at Connected Places Catapult to champion Project Acorn through our integral role in the Hydrogen Innovation Initiative. We have brought together key players to collaborate and tackle head-on the technological and regulatory challenges facing transport decarbonisation and, in this particular case, aviation. Our collective work is critical in driving us towards net-zero goals, ensuring a sustainable future. Strengthening the UK’s position as a global leader in cutting-edge innovation.”
Jacobs Senior Vice President Kate Kenny said: “Supporting this groundbreaking operational trial continues Jacobs’ strong track-record in industry-leading hydrogen aviation research projects, such as FlyZero and Zero Emission Flight Infrastructure. By investing in understanding the use of hydrogen in a live airport environment we hope to help move aviation an important step closer to decarbonisation and a net-zero future.”
Information on Project Acorn members:
About easyJet
easyJet is Europe’s leading airline offering a unique and winning combination of the best route network connecting Europe's primary airports with great value fares and friendly service.
easyJet flies on more of Europe’s most popular routes than any other airline and carried more than 82 million passengers in 2023 with more than 11.3 million travelling for business. The airline has over 300 aircraft flying on nearly 1000 routes to more than 155 airports across 35 countries. Over 300 million Europeans live within one hour's drive of an easyJet airport.
easyJet aims to be a good corporate citizen, employing people on local contracts in eight countries across Europe in full compliance with national laws and recognising their trade unions. The airline supports several local charities and has a corporate partnership with UNICEF which has raised nearly £17m for the most vulnerable children since it was established in 2012.
In 2022, easyJet published its roadmap to net zero by 2050. The roadmap, which also features a combination of fleet renewal, operational efficiencies, airspace modernisation, Sustainable Aviation Fuel and carbon removal technology, has set an ambitious interim carbon emissions intensity reduction target of 35% by 2035. The airline’s ultimate aim is to fully transition its fleet to zero carbon emission technology, which it will achieve through a number of strategic partnerships including with Airbus, Rolls-Royce and GKN Aerospace Solutions. Since 2000, the airline has successfully reduced its carbon emissions per passenger, per kilometre by one-third.
Innovation is in easyJet’s DNA – since launching nearly 30 years ago, easyJet changed the way people fly to the present day where the airline leads the industry in digital and operational innovations to make travel more easy and affordable for its passengers.
In 2023 easyJet was named by TIME as one of the World’s Best Companies and a Leader in Diversity 2024 by The Financial Times.
About Bristol Airport
Bristol Airport is England’s third largest airport outside of London, connecting our region with more than 120 destinations, including vital economic links to European cities and parts of the UK that cannot be easily reached by train. We have taken a leading position on sustainability, aiming to be the first airport in the country to achieve net zero carbon operations by 2030. Our operations were independently accredited as being carbon neutral in 2021, four years ahead of our target.
About Cranfield University
Cranfield is a specialist postgraduate university that is a global leader for education and transformational research in technology and management. The most recent Research Excellence Framework results demonstrate Cranfield University’s excellence with 88% of research rated as world-leading or internationally excellent.
Cranfield is the number one university in Europe for aerospace and is one of the few universities in the world to have its own airport. Our global research airport offers a unique environment for transformational research. Interconnectivity between our facilities and across academic disciplines is enabling us to rethink the airports, airlines, airspace management and aircraft of the future in a holistic way.
About Cranfield Aerospace Solutions
CAeS is a UK-based aviation pioneer which is developing world-leading hydrogen propulsion system technology for aircraft, with the aim to deliver the world’s first, zero-emissions passenger aircraft solution by 2026 with the conversion to the Britten Norman Islander. Through the development of a modular architecture and proven integration capabilities, the company is able to adapt the technology for use on multiple platforms, driving the transition of the aviation industry to zero-emissions flight.
About Connected Places Catapult
Connected Places Catapult is the UK’s innovation accelerator for cities, transport, and place leadership. We provide impartial ‘innovation as a service’ for public bodies, businesses, and infrastructure providers to catalyse step-change improvements in the way people live, work and travel.
We connect businesses and public sector leaders to cutting-edge research to spark innovation and grow new markets. We run technology demonstrators and SME accelerators to scale new solutions that drive growth, spread prosperity, and reduce carbon emissions.
More about the Hydrogen Innovation Initiative: https://hydrogeninnovation.co.uk/
About DHL
DHL is the leading global brand in the logistics industry. Our DHL divisions offer an unrivalled portfolio of logistics services ranging from national and international parcel delivery, e-commerce shipping and fulfillment solutions, international express, road, air and ocean transport to industrial supply chain management.
With about 395,000 employees in more than 220 countries and territories worldwide, DHL connects people and businesses securely and reliably, enabling global sustainable trade flows. With specialized solutions for growth markets and industries including technology, life sciences and healthcare, engineering, manufacturing & energy, auto-mobility and retail, DHL is decisively positioned as “The logistics company for the world”.
About Globe Fuel Cell Systems
GLOBE Fuel Cell Systems is a German GreenTech company from Stuttgart, Germany. GLOBE has set itself the task of supporting the industry on the path to decarbonization towards a carbon-free future with fuel cell technology. GLOBE develops and produces digitally connected, modular fuel cell systems for a wide range of industrial applications. GLOBE has its origins in fuel cell research and the innovation department of Mercedes-Benz.
About Jacobs
At Jacobs, we're challenging today to reinvent tomorrow by solving the world's most critical problems for thriving cities, resilient environments, mission-critical outcomes, operational advancement, scientific discovery and cutting-edge manufacturing, turning abstract ideas into realities that transform the world for good. With approximately $16 billion in annual revenue and a talent force of more than 60,000, Jacobs provides a full spectrum of professional services including consulting, technical, scientific and project delivery for the government and private sector. Visit jacobs.com and connect with Jacobs on Facebook, Instagram, LinkedIn and X.
About Mulag
MULAG is one of the leading German manufacturers of high-tech products and special solutions for airport ground support and roadside maintenance vehicles. The well-known MULAG quality is based on decades of experience in special vehicle construction:
Our roadside maintenance business division manufactures reliable products for mowing and other roadside maintenance tasks. Front and rear-mounted attachments and mowing combinations come with a multitude of working attachments and are optimally suited for all-year use with Mercedes-Benz Unimog and other carriers.
As manufacturers of vehicles for airport ground support and for use in industry, we furthermore place much emphasize on the development and production of a wide range of products, including tractors, conveyor belt vehicles, container pallet transporters, and special vehicles. For years, alternative drives powered by hydrogen fuel cell or electricity have played a major role in our product strategy for emission reduction.
Quality, environment and energy are key to MULAG's corporate success and have great importance for our products and our production. From our extensive experience in the field of vehicles and attachments, standards have developed in these key areas with the claim of a market leader. Since 2021, MULAG has been sourcing 100% of its electricity from renewable sources.
The RenewablePLUS certificate guarantees that the electricity generated is entirely from renewable energies. In addition, the expansion of renewable energies is promoted through further ecological measures and investments in the plants. Through climate protection projects of the ÖkoPLUS quality label, all associated CO2 emissions are made climate neutral.
More about MULAG and its sustainable solutions www.mulag.com
About TCR
TCR is a pioneer and world leader, specialised in Ground Support Equipment (GSE) all around the world. TCR offers an exhaustive range of solutions and services to support air industry customers with the vital aspect of their ground handling processes: the use and operation of all their GSE equipment.
As a leading global provider of GSE rental solutions and services, TCR Group excels in Full Service Rental, Maintenance & Ramp Assistance, and Fleet Services for major ground handlers, airlines and airports throughout the world. TCR always goes further to meet today’s environmental challenges:
after an initial period of rental, a large range of refurbished second-hand GSE equipment – meticulously maintained in our TCR workshops – is also made available for sale across our global network.
Our TCR solutions reduce your GSE-related total cost of ownership in full transparency, by guaranteeing that only the required and appropriate GSE mix is available and fully operational exactly when and where it is needed.
Our priority: to provide our customers with timely, dedicated, reliable and high value-added GSE in the safest environment.
