T-Mobile's Deeanne King says smarter buildings and solar are cutting both emissions and costs

Deeanne King, executive vice president and chief people officer at Bellevue, Wash.-based T-Mobile, who also helps lead the company’s sustainability work, says the biggest gains often come from doing the basics well. Managing building heating and cooling more intelligently produced nearly US$5 million in estimated energy savings in 2025.

T-Mobile had 132 community solar projects in its portfolio as of 2025, with an estimated lifetime saving of US$60 million in energy costs, and its total emissions in 2025 were 50% lower than its 2020 baseline. The company has signed the Climate Pledge, committing to net-zero carbon by 2040.

“You can’t let the size of the problem become the reason you don’t start,” King said. “When something feels enormous, I focus first on what we can control.”