Sønderborg, Denmark, aims to be carbon-neutral by 2029. It aims to do this by generating power and heat from renewable sources and making its buildings more energy-efficient. "[W]e’ve adopted a holistic approach that’s bottom-up. It’s not just top-down, about planning and coming up with business and new technology to drive this forward," said project director Christian Eriksen. "It’s also very much about participation, about learning, and empowerment of our citizens and local companies."