Bethany Patton steps up to the counter at a Starbucks in Tempe, Arizona. She places her pink mug into a shoebox-sized dishwasher. It spins. It whirs. Water splashes inside. After 90 seconds, the door opens. A barista grabs the mug and prepares Ms. Patton’s coffee.

The disposable Starbucks cup is an icon. People recognize the logo and brand of the biggest coffee shop chain in the world. But Starbucks wants to stop using disposable cups by 2030. Why? Because they create a lot of waste.

At the store where Ms. Patton gets her coffee, Starbucks has already stopped using disposable paper or plastic cups. Customers who don’t bring their own get a reusable plastic one. When they’ve finished their coffee, they can drop the cup into a nearby bin. Starbucks is testing this approach at two dozen stores.

Cups too damaged to be reused are shredded, melted, and built into boxes. Those become the return bins for the reusable cups.

Starbucks workers are also developing disposable cups that use less material and are more recyclable. That’s a tough project. Paper pulp from recycled cups has shorter fibers than virgin (never used) pulp. That means the cup has less rigidity or stiffness. That’s important for keeping hot drinks out of your lap!

The lining inside a disposable cup keeps a hot liquid from quickly breaking down the paper. It’s made of polyethylene. That’s a heat-resistant plastic. Plastic lining and flids are hard to recycle.

There will always be some waste with disposable cups. That’s why the company wants to switch to reusable.

Valencia Villanueva is a barista at the Tempe store. She thinks Starbucks will succeed in its goal. “[No customers have] complained and said they wanted a single-use cup,” she says.