The aviation industry accounts for approximately 2% of the global greenhouse gas emissions. Consequently, the industry is dedicated to find solutions that can reduce the climate impact of air transport, which is expected to increase year on year.
The growing deman for global air transport also means that the industry’s greenhouse gas emissions will increase. This development underscores the need for the aviation sector to take action in order to meet the goals outlined in the Paris Agreement. In this context, new and more increasingly sustainable aviation fuels play a pivotal role in reducing the climate impact. However, optimising and improving operations and infrastructure, as well as developing new aircraft engines and advanced technologies, are also crucial to reduce aviation emissions.
Therefore, DCC & Shell Aviation Denmark is engaged in Green Power Denmark’s PtX partnership. Additionally, we support Arcadia eFuels’ ambitions for PtX production in Vordingborg and a development project at Aalborg University, where wastewater sludge and wood waste are being converted into more sustainable fuels for air and maritime transportation.
How we optimise our operations
In Denmark, DCC & Shell Aviation has long been dedicated to optimising and improving our daily operations and infrastructure.
At Billund and Copenhagen Airports, our refuelers and dispensers currently operate on the biofuel HVO (Hydrotreated Vegetable Oil). Very soon, we will introduce the first electric-powered refueler as a step toward electrifying our fleet at the airports.
At the other Danish airports, our refuellers today operate on the natural gas-based GTL (Gas-to-Liquid) fuel. GTL burns cleaner than regular diesel, contributing to a better working conditions for our employees while also helping to prevent operational disruptions.
Bio-based SAF (Sustainable Aviation Fuel)
The greatest potential for reducing CO2 emissions in the aviation industry is to replace fossil-based jet fuel with non-fossil alternatives. Currently, this is achieved through bio-based Sustainable Aviation Fuel (SAF).
SAF is a collective term for aviation fuels produced from non-fossil sources. One significant advantage of SAF is its seamless integration into the global aircraft fleet and existing fuel infrastructure in and around airports.
Today’s SAF is typically produced from waste biomass, such as used cooking oil. In the future, however, eSAF—produced from renewable energy in a Power-to-X (PtX) facility—is expected to become widely available for the aviation industry on a large scale.
The pure SAF component is also referred to as Synthetic Paraffinic Kerosene (SPK), though it is not yet approved by engine manufacturers for 100% use. As a result, SAF is classified as a drop-in fuel, meaning it can be blended with conventional JET A1 fuel at ratios of up to 50%. Nevertheless, companies like Airbus and GE Aviation are already testing flights powered entirely by SAF. At blending ratios of up to 50/50, SAF is classified as JET A1, making it identical to fossil-based JET A1.
Electricity as Liquid Fuel – Power-to-X
The electrification of aviation is currently limited by the weight, size, and relatively low energy capacity of batteries. As a result, electric propulsion is primarily expected to become relevant for smaller regional aircraft.
For short and medium-haul aircraft, green hydrogen and Power-to-X (PtX) hold significant potential to reduce the CO2 emissions from the aviation industry through synthetic eSAF (electrofuels). PtX is a high-tech process that uses electrolysis to convert renewable energy from wind, solar, or hydropower into liquid fuels, such as eSAF or eMethanol.
Hydrogen produced in this process can be used either directly as fuel or transformed into liquid fuel through a carbonisation process. Carbonisation requires CO2, which can either be captured from biofacilities or extracted directly from the atmosphere, a method known as Direct Air Capture (DAC). The carbon (C) from the CO2 is combined with green hydrogen to form CH compounds, which ultimately become, for example, green aviation fuel.
Scaling up Power-to-X production to a commercial level and ensuring the safe handling of liquid hydrogen require substantial investments and continued technological advancements. Denmark is among the global frontrunners in this field. Several large-scale PtX projects are currently underway in Denmark, which aim to support the transition of aviation towards more sustainable fuels.
Learn more about our partnership with Arcadia eFuels here.
RefuelEU Aviation
Starting in 2025, the RefuelEU Aviation directive mandates that 2% of SAF (Sustainable Aviation Fuel) must be blended into all jet fuel supplied to European airports. The blending requirement will gradually increase, reaching 70% SAF by 2050, of which 35% must be synthetic fuel, such as eSAF.
By 2030, RefuelEU Aviation requires a 6% SAF blend in all jet fuel used at European airports. Of this, an average of 1.2% must be eSAF—a figure that will steadily rise to meet the 2035 target of 20% SAF, including 5% eSAF.
Learn more about RefuelEU Aviation here.
Book & Claim: Integrating SAF into
Existing Infrastructure
The large-scale rollout of SAF (Sustainable Aviation Fuel) and, later, Power-to-X-based aviation fuels in Denmark and internationally requires a robust and stable supply chain that integrates seamlessly with the existing fuel infrastructure. The alternative—establishing an entirely separate infrastructure solely for SAF—would significantly increase CO2 emissions and lead to costly and inefficient logistics.
This is where the Book & Claim principle comes into play. Book & Claim is a model similar to the system used for green electricity in Denmark’s electricity grid, where the purchase of green energy—or in this case, SAF—occurs separately from the physical product. Essentially, the customer “claims” a specific share of a total pool of SAF supply that has already been delivered to Denmark’s aviation fuel infrastructure. The supplier “books” the purchase in the system, issuing a unique certificate to guarantee the customer’s share of SAF, and that the same quantity of SAF is only sold once.
In the future, as SAF becomes an increasingly larger share of aviation fuel supplies, the Book & Claim model is both scalable and logistically realistic. Unlike today, where DCC & Shell Aviation Denmark supplies specific customers with SAF directly due to the early stage of development, large-scale distribution to airports and private customers across the country will not be feasible using the current approach.
Instead, SAF will be supplied to fuel systems at specific airports. The quantity will then be registered and verified, and the CO2 emissions from the fuel will be calculated. Customers’ individual purchases and use of SAF, along with the corresponding emissions reductions, will be certified based on the total volume supplied.
Currently, the global acceptance and adoption of Book & Claim as a universal model for managing and controlling a large-scale SAF rollout are still developing. However, companies such as Shell are collaborating with Accenture and American Express to develop a digital platform for Book & Claim, which could serve as the backbone for this system worldwide.
