After
winning €1 million in the Bloomberg Mayors’ Challenge in 2015, Stockholm built a pyrolysis plant which produces around 300 tonnes of biochar each year, equivalent to taking 700 cars off the city’s roads each year.
What’s more, rather than wasting the enormous amounts of energy generated in the production of biochar, the city is using it to power its district heating network.
The waste, energy and parks departments joined forces to develop the process. “We realised there was the potential to go beyond carbon neutrality,” says Dahllof.
The biochar project is one of the major initiatives Stockholm is trialing as part of its ambitious climate strategy. By 2040, the city aims to reach net-zero emissions.