Three ancient oaks saved as Fortum Värme builds biofuel CHP

Green thinking permeates the design and operations of Fortum Värme’s newly started combined heat and power plant in Sweden. The plant is even designed with inward curves to precisely fit in between three majestic oaks. That might sound peculiar at first, especially considering the plant is fuelled with forest residuals.

The explanation is, of course, that trees are scarce in the Värtan part of Stockholm where the plant is situated, near Värtahamnen. Mats Strömberg, Project Director, who initiated the construction of the plant in January 2013, says an environmental ruling simply demanded that the trees were preserved.

“We also set requirements for our contractors that the oaks should not be damaged. Today we are proud to show you the plant with the oaks around it,” Strömberg says.

The biofuel-fired combined heat and power plant was inaugurated in early May 2016, and it is an important step in developing a sustainable energy supply for Stockholm. The plan is for district heating in Stockholm to be entirely produced from renewable and recovered energy by 2030.

The Fortum Värme plant, equally owned by the City of Stockholm and Fortum, will produce 750 GWh of electricity and 1,700 GWh of heat annually. That is enough to heat around 190,000 average-sized apartments.

“It is the world’s largest power plant that is adapted 100% to biofuel”, says Strömberg.

Fuelling with forest residuals is expected to decrease carbon dioxide emissions by 126,000 tonnes a year, the equivalent of six weeks’ worth of emissions from all the road traffic in Stockholm. Some 40% of the bark and wood chips arrive by train at Värtahamnen, with the remainder arriving by ship from the Baltic countries.

NIB is co-financing the power plant with a SEK 1.4 billion loan signed with Fortum Värme in June 2014. The long-term loan has a maturity of 12 years. The loan is fully financed with proceeds from NIB’s Environmental Bonds.

However, the financial long-term aspect nevertheless seems short amid the three oaks in Värtan. Considering how technology for renewable energy has progressed over the last hundred years, it seems quite likely that oak trees several hundred years old can outlast even the brand-new power plant in Värtan.