When you think of the airline industry, electrification might not come to mind. But what’s happening “below wing”—where workers fuel planes, load, unload and transfer baggage and cargo, and perform essential maintenance—is a different story, and Delta Air Lines is leading the way at Denver International Airport (DIA).
From 2024 to 2025, Delta received four grants from the Colorado Clean Diesel Program (CCDP) to help purchase six electric baggage tugs and seven electric belt loaders. Baggage tugs move carts that hold luggage between bag rooms and planes, dropping cargo in front of the aircraft for belt loaders. Belt loaders then load the luggage into the cargo bay with conveyor belts. Electrifying 13 of these ground support equipment (GSE) units marks a major step forward at DIA.
Early adopters like Delta are crucial for bolstering the growing electric GSE industry. They provide market validation and potential for scaling up, which can eventually lower costs.
“The CCDP grant is necessary to make new and expensive equipment more affordable than diesel units—and it’s better technology,” says Louis Lammers, fleet strategy specialist with Delta.
For the Colorado Department of Public Health and Environment, which contracts with Clean Energy Economy for the Region (CLEER) to manage the Colorado Clean Diesel Program, Delta’s adoption aligns with broader efforts to improve and protect outdoor air quality.
“Diesel replacement projects not only reduce health risks, but also create long-term economic benefits, support local jobs, and strengthen the resilience of our communities,” says Michael Ogletree, senior director of air quality programs.“These investments deliver real returns by securing a stronger and prosperous future for Colorado.”
Switching to electric GSE, however, isn’t without challenges. Charging infrastructure varies at every airport and terminal, and introducing new equipment requires crews to adapt to different workflows. Despite these hurdles, Delta has moved forward, electrifying 24% of their ‘core’ equipment (bag tugs, belt loaders, and pushback tractors) at DIA in 2025. For Delta’s Denver crew, the switch has not only been easy, but welcomed. Crews have quickly adapted to the new features and charging routine.
The Colorado Clean Diesel Program sat down with Delta to learn about its growing electric GSE fleet. Contributing to this Q&A were fleet strategy engineer Gabriella Lowy; fleet strategy specialist Louis Lammers; ramp operations service manager Kevin Kanellakis; and aircraft load agents Jacob Baylor, Blaine Gilberton, Marlon Johnson, and Devin Elder.
What’s the biggest difference you notice in operating electric baggage tugs and belt loaders compared to diesel equipment?
For us to get brand new equipment, it was a booster for the team. Most of our equipment is diesel and older, so it can break down. The electric belt loaders are also just a lot simpler in terms of parts cost and reliability. For the most part, these [electric belt loaders and bag tugs] turn on easily in the morning, the heat is on, and everything’s good to go. In the diesel ones, they are loud and as soon as you finish your day, you can feel yourself covered in just fumes. With these, you don’t have to worry about the exhaust. There’s also a safety feature in the electric tug that automatically slows the vehicle down when you let go of the gas. You won’t continue rolling, even if you’re in neutral or in gear.
What are the upfront costs of going electric?
The biggest difference comes from supplying the battery. Base costs for a diesel versus electric unit are about the same, but usually the batteries you’re putting in (several vendors don’t include the battery) add an extra $10–15,000, depending on the battery or how many battery packs we need. With belt loaders, you’ll see a bigger cost difference because of added technologies like collision avoidance that you wouldn’t see on a diesel unit. You’re paying more, but you’re also getting advanced technology and safety features.
What are the lifetime savings?
The fuel cost savings have always been there, but that’s just one of the projected cost savings. We have quarterly checks at the shop where GSE gets tires and glass inspected, and more generally, make sure everything’s good. We’re seeing about a two hour reduction in that process because there are not as many parts in the drivetrain or engine to service. We’re also seeing a labor hour reduction. As this technology develops, it’s become more reliable. We hope to see that trend continue in the future.
What’s your biggest uncertainty about the equipment?
The biggest question is: how will the batteries hold up over time? You’re charging and discharging these batteries all day, and that can deteriorate the battery health depending on the behavior of the driving and charging. We have a couple of plans on how we can recycle the batteries through our fleets, including cascading batteries to downline stations that do not need as much efficiency out of their battery. Because we have mostly new electric equipment, we haven’t enacted this yet, but it should be about 5 years.
With such a busy airport, how does charging work?
Wherever we have charging available, we try to deploy electric equipment. The easiest way to charge the baggage tug is when someone’s on break with the smart charging feature, which automatically directs power to the GSE that needs it most, topping them up within 30 minutes. For belt loaders, they charge at night or in between flights.
Why does Delta Air Lines care about electrification?
Delta is committed to Net-Zero carbon emissions by 2050. Planes are the biggest emitters in our industry, but changing that is not feasible right now. The way to cut down on carbon emissions in the near future is through ground support equipment. We have 40,000 active pieces of equipment across all airports, so it’s a big deal to get those electrified. From an employee standpoint, Delta wants to invest in the people working below wing. It’s a chaotic environment, so the electric equipment’s advanced safety features are especially valuable.
The Colorado Clean Diesel Program makes grants to businesses to help offset the cost of replacing certain off-road diesel equipment with all-electric or hybrid-electric equivalents. To learn more about current grant opportunities, visit our homepage.
