Finnish energy company begins burning cashew nut shells for heat production

Helsinki’s energy provider Helen has started using cashew nut shells imported from Ivory Coast as a fuel source for district heating, Helsingin Sanomat reports. The shells, a byproduct of food processing, were shipped to Finland in late April.

Janne Kerttula, head of the energy systems unit at the Finnish Energy industry association, confirms that global agricultural and industrial processes generate a wide range of waste streams now repurposed for energy. “The only limit is imagination,” he says. Olive pits, coffee grounds, and corn cobs—left over after kernels are removed—are commonly burned for heat and power in Europe. Even chicken manure is used as a combustible fuel.

Some critics have questioned the emissions impact of transporting cashew shells from Africa. Helen defends the practice, stating that the shells produce nearly twice the heat output of domestic wood chips, a common forestry byproduct. Kerttula notes that maritime shipping remains one of the most energy-efficient and low-emission transport methods for bulk materials.

Finland’s cold climate and high heating demand make it particularly effective at utilising imported waste streams, Kerttula explains. “In warmer countries, only part of the energy content might be recovered, for example as electricity. Here, we can extract nearly all of it for heating.”

Domestic wood chips, while locally sourced, still require long-distance transport to meet Helsinki’s energy needs, he adds. Finland’s efficient use of industrial byproducts has driven demand for materials that might otherwise go to waste elsewhere.