How Delta Marked Its 100th Year With Clean Energy Successes

For an airline celebrating 100 years since its founding in Macon, Georgia, Delta’s 2025 was anything but nostalgic. From operational energy gains to novel aircraft technologies, its progress over the past 12 months speaks to how aviation’s big players are now acting as energy companies in their own right.

In the first quarter alone, Delta surpassed its short-term fuel efficiency goal, saving more than 55 million gallons of jet fuel through operational improvements.

These savings equated to over US$125m and made a meaningful dent in its carbon footprint.

Energy performance and smarter operations

At the heart of these gains lies Delta’s cross-enterprise Carbon Council, a team tasked with driving energy efficiency through precision measures. These included weight reduction across the fleet, enhanced APU tracking, optimised flight routing, new landing procedures and aerodynamic refinements such as 'winglets’.

Individually modest, these projects collectively delivered significant energy savings across Delta’s network. The company also launched its ‘Green Station of the Year’ initiative, designed to embed energy-conscious practices among ground and flight crews.

Through friendly competition, staff have been encouraged to rethink their own energy habits, which is proof that behaviour change remains a cornerstone of any meaningful energy transition.

Delta's new wave aircraft partnerships

Technology partnerships were another energy milestone for Delta this year. In March, it joined forces with aerospace start-up JetZero to support the development of a blended wing-body (BWB) design.

The futuristic aircraft is predicted to be up to 50% more fuel efficient than current models, with Delta offering operational expertise through its Sustainable Skies Lab to help bring the project to market.

Later in the year, Delta entered a separate collaboration with Maeve Aerospace aimed at accelerating hybrid-electric aircraft for regional routes. Maeve’s aircraft could cut fuel emissions by up to 40% when using conventional jet fuel, and potentially even more when operating on SAF.

“As we work toward the next generation of aircraft, we look to partners like Maeve who embody the bold, forward-thinking innovation we champion at Delta – solutions that advance aircraft design, enhance operational efficiency, elevate employee and customer experiences, and cut emissions,” says Kristen Bojko, Vice President of Fleet at Delta Air Lines.

Blue sky thinking

In 2025, Delta expanded its partnership with Airbus to test ‘fello’fly’ – a concept inspired by migrating birds that allows two aircraft to fly in formation to cut energy use.

Airbus estimates that this approach can save around 5% of fuel for planes on long-haul routes.

The airline also added Australian start-up MicroTau to its Sustainable Skies Lab, which has created shark-skin-like coatings for aircraft to reduce drag. This has the potential to improve fuel efficiency by up to 4%.

Alongside this, new component upgrades such as finlets and split-scimitar winglets have been introduced to reshape airflow and reduce drag across older fleets.

While these energy savings are not particularly large when taken individually, combined they can really turn the dial. This is the story of the energy transition in the notoriously hard-to-abate aviation sector: small, marginal gains in pursuit of net zero.

Scaling sustainable aviation fuel

Delta’s biggest energy milestone came from its investment in SAF, an area where global supply remains tight. In 2025, the airline partnered with Shell Aviation, Montana Renewables and the Port of Portland to facilitate the first commercial-scale SAF delivery to Portland International Airport.

According to Airbus, SAF can reduce lifecycle emissions by up to 80% and may even achieve net negative impacts when produced from advanced feedstocks. Delta’s commitment to scale its SAF use by 50% year-on-year demonstrates the growing role of low-carbon fuels in reshaping aviation’s energy mix.

Fast Company recognised Delta among the world’s Most Innovative Companies for its SAF leadership, underscoring how energy transformation and business innovation increasingly go hand in hand.

What do energy-efficient aircraft look like?

Delta aims to introduce more than 35 next-generation aircraft by early 2026, each delivering an average energy efficiency improvement of over 25% per seat mile compared with the aircraft retired since 2019.

Given that around 90% of the airline’s carbon output stems from jet fuel, these gains mark a critical lever in cutting aviation’s energy intensity while newer propulsion technologies continue to mature.

Rethinking energy on the ground

Sustainability on the ground received attention too. In 2025, Delta transitioned entirely from plastic to paper cups across all flights, a move supported by new energy-aware logistics systems.

At its Seattle facilities, Delta opened the Delta One Lounge and a new Sky Club – both running on all-electric energy, incorporating smart windows and motion-sensing lighting to reduce consumption.

The airline also deepened its partnership with Green Taxi Aerospace to explore electric taxiing technology—an innovation expected to cut energy use and carbon emissions during ground operations.

The Georgia-based company also opened new facilities at Seattle-Tacoma International – the Delta One Lounge and a second Delta Sky Club.

Both these areas were created with sustainability in mind and include smart windows that adjust to sunlight, all-electric energy with motion-sensing lights and reusable dinnerware to reduce waste.

The airline also partnered with Green Taxi Aerospace to explore electric taxiing technology that aims to reduce fuel use, operating costs, taxi time and carbon emissions.

A year of "meaningful steps"

“As Delta Air Lines closes out its centennial year, we’re proud to share the meaningful steps we’ve taken toward a more sustainable future of flight,” says Amelia DeLuca, Chief Sustainability Officer at Delta.

“These milestones reflect Delta’s commitment to transforming the future of flight.”

For Delta, 2025 has been less about marking a century of travel and more about charting a new energy frontier – proving that the path to net zero in aviation is one powered by innovation, efficiency and collaboration.