By RoschetzkyIstockPhoto / Getty Images In the spring, the capital of Colorado, Denver, launched a vast voucher scheme encouraging people to buy electric bikes, supporting low-income residents in particular. Six months later, the program is proving successful. In the spring, the capital of Colorado, Denver, launched a vast voucher scheme encouraging people to buy electric bikes, supporting low-income residents in particular. Six months later, the program is proving successful. The program’s maximum threshold of $4 million was reached in just six months, indicating that demand was particularly …