Inside Delta’s plan to take single-use plastic cups off its flights | Trellis

Oct 17, 2024

The cup redesign will cut 7 million pounds of plastics annually, cutting in-flight waste. Read More

Delta Air Lines, after two years of prototyping and testing, will replace single-use plastic cups with recyclable paper ones on transcontinental flights by the end of the year. From there, the airline will transition domestic U.S. journeys in 2025.

It is an exercise that will decrease the plastic Delta sends to landfills. It won’t have a tangible impact on decarbonization. Jet fuel accounts for 90 percent of the airline’s greenhouse gas emissions.

Alaska Airlines was the first airline to make this move, finishing the project in August 2023. That transition eliminated 55 million single-use plastic cups annually, or about 2.2 million pounds of plastic waste. Delta’s cup redesign will cut 7 million pounds of plastics annually, or the weight of about 1,300 pickup trucks. That’s on top of the 4.9 million pounds of single-use plastics it has saved since 2022. The airline declined to reveal how many cups it will replace, but a spokesperson said it serves 200 million customers annually.

Delta already eliminated most plastic water bottles and other items from its flights. Changing to one universal, 10.5-ounce drink cups to serve cold, hot and alcoholic beverages — instead of using both plastic ones and paper ones in flight — is a sustainability measure that also appeals to consumers frustrated by single-use plastic waste, said Amelia DeLuca, chief sustainability officer at Delta.

Aviation accounted for about 2 percent of the world’s carbon footprint in 2022, and the biggest culprit was jet fuel. Delta is investing in sustainable aviation fuel, or SAF, made from renewable sources such as agricultural waste, cooking oil and animal fat. Its goal is to substitute at least 10 percent of its annual fuel consumption with SAF by 2030, and as of April it had signed contracts covering about half that volume.

While SAF will be important, it currently isn’t in abundant supply. Technology improvements to make planes lighter, updates in energy efficiency, and optimizations for flight, ground and traffic management will be critical for driving “small but material” reductions until at least 2040, according to an aviation industry analysis by consulting firm Oliver Wyman.

With that in mind, Delta is prioritizing ways to cut how much jet fuel it burns. In 2022 alone, it introduced measures such as enhanced winglets to reduce drag that cut 10 million gallons in fuel. Delta is on pace to cut 1 billion gallons of fuel cumulatively between 2019 and 2035, about one-quarter of what it uses annually.

“There is a ton of work being done to save fuel,” she said. “We’re doing our part both in front of their eyes and behind the scenes.”

Delta considered multiple suppliers while planning how to ditch single-use plastic. The airline evaluated potential partners for pricing and specific supply chain considerations, including financial strength and risks such as geography and allocation. Delta’s design and sustainability teams even visited factories where potential suppliers would produce the paper cups.

It ultimately decided on a new one, Blulabs, during the final prototyping and testing phase in early 2024. Blulabs is a private, family-owned company with annual revenue in the low nine figures that boasts customers in aviation, food service and retail; Walmart and Disney are accounts.

“Delta came to us after they conducted their own research years ago as they looked for a new alternative to plastic cups used onboard,” said Cole Garson, president of Blulabs.

That was two years ago. Since then, there have been at least three distinct rounds of in-flight testing, looking at metrics including leakage, heat transfer and impacts on catering efficiency. Here are factors that made the project tricky.

1. International regulations

Specialized material is needed to hold hot and cold drinks, including alcoholic beverages, which can dissolve paper. Traditional paper cups come with a polyethylene liner, but that makes them difficult to recycle. Delta sought recyclable cups that are also home and industrial compostable, so they comply with European standards.

The cups supplied by Blulabs are certified as “plastic-free” by certification agency Flustix. In reality, that means they contain less than 0.75 percent plastic. The cups have a primarily aqueous liner, which means they can be recycled in traditional paper recycling systems that the airline already uses. Delta will offer a single cup size on flights. Previously it stocked two sizes.

2. Flight attendants’ expectations

One of the most difficult parts to engineer was how the cups stack on drink carts and how easily they can be separated — with just one hand — to pour liquid into them. “That’s a really disruptive thing for flight attendants,” Garson said. “They care a lot about the cup.”

The height and bottom diameter of early prototypes were adjusted to ensure drawers on flight carts could hold as many cups as possible without their sticking together.

Delta’s flight crews, catering and operations teams were closely involved in the process, from the beginning, DeLuca said. Many were “passionate” and vocal about the need for this change. “Go where your employees want to go,” she said.

3. New shapes require new production molds

Blulabs is a vertically integrated operation, but the Delta cups are unique in shape and production process. Each includes two layers that are wrapped over the mold. Every time a change is made, the molds need to be updated.

Meanwhile, Blulabs is working closely with Delta to ensure that enough manufacturing space is allocated to ramp up production. “It was a lot of trial and error on the workshop floor,” Garson said. “We had a full team of engineers and project managers, not just here in the United States but over in China, that were iterating consistently on very tough deadlines and fast timelines.”

Delta’s phase-in timeline will be coordinated with supply levels of existing cups within its catering operations, according to Deluca. As inventory is depleted in Delta’s operational hubs, and new orders need to be placed, the new cups will be phased in.

Future ideas for lightweighting include an expansion of Delta’s program to let customers pre-select their meals before a flight, which will help crews optimize the food that’s loaded onto planes. Currently, this service is only offered to those flying with a premium ticket.

“We’re working on the things we can control,” DeLuca said.