Denver launched a rebate program to encourage residents to buy e-bikes and drive less. It’s already wildly popular.

The first set of 3,000 vouchers—with $400 for a standard rebate, $1,200 for low-income residents, and an extra $500 for anyone buying an electric cargo bike—were claimed within days of the program’s launch last April. Then the city released more vouchers in July, and “they were gone in 22 minutes,” says Grace Rink, the city’s chief climate officer. “We thought it might be popular. We just didn’t know how popular it was going to be.”