Many routes to carbon sinks in the City of Malmö

The City of Malmö is one of Sweden’s leading municipalities when it comes to the climate transition, although they do not do everything themselves but rather engage outside help as well. This included the municipality signing an innovation partnership agreement with RISE in December 2021. This entails RISE helping the City of Malmö with many different projects, such as investigating the challenges preventing them from achieving a fossil-free electricity supply or greenhouse gas emissions from municipal operations.

One of the assignments that has already been completed is an investigation showing how the City of Malmö can cut its climate impact by identifying possible carbon sinks.

“A carbon sink is a function or a process in which carbon dioxide is captured from the air and stored,” says Tora Råberg, a researcher at RISE’s Agrifood unit.

She headed the work with the report, and in doing so enlisted the help of many different colleagues.

“I was the coordinator of an entire team here at RISE, with each member an expert in their particular field. This meant that we had access to broad specialist knowledge, ranging from how to calculate carbon storage in wooden structures to what actually happens chemically during pyrolysis when carbon is not fully combusted.”

Many different opportunities

The various opportunities and solutions presented in the report show great breadth. The use of bio-based materials in new builds is expected to offer the greatest opportunities for creating negative emissions, such as by using wood instead of concrete. Almost as much potential is shown by an agricultural transition within crop cultivation, with a carbon sink comprised of a larger carbon store in the form of biochar and increased humus content in soil. Together, these two represent more than eighty percent of the potential available to the municipality.

“This report is based solely on current conditions in Malmö and the surrounding area, and we hope that it will provide an important building block in the decisions that the city makes concerning carbon sinks.”

Survey of technological maturity

However, it is not only potential carbon sinks that have been identified. With the help of colleagues at RISE, Råberg has also surveyed the maturity of the technology needed to realise these carbon sinks.

“We’ve also looked at the cost per CO₂ equivalent, the scalability of the solutions, and the potential spinoff effects they could offer, such as increases in biodiversity and improvements in soil structure. All of this has been possible thanks to RISE’s interdisciplinary approach.”

Moreover, the expert knowledge that RISE contributes is greatly appreciated by the City of Malmö.

“Naturally, those of us working at the Environmental Department are specialists but producing a report like this requires even greater expertise,” says Gunilla Andersson, a project manager at the City of Malmö.

“Since our innovation partnership with RISE was already in place, it was natural to turn to them, as RISE has that greater expertise in a number of different areas.”

Scientific basis

Moreover, Andersson underlines that it was important that the report was produced on the basis of the scientific method.

“We don’t have the research expertise, databases or resources available to RISE, so this partnership has been of great value to us. Now it’s simply a matter of applying the results to our reality.”