In Sweden district heating is the most widespread heating technique for heating properties. Since district heating was established, emissions of both sulfur and carbon dioxide have been substantially reduced. The Swedish energy company Kraftringen, partner in the CITyFiED project in Lund, delivers district heating to 20,000 households. The project consortium recently conducted a visit of Kraftringen’s production plant called Örtoftaverket.
Örtoftaverket is a biomass-fired combined heat and power plant that produces both district heating and electricity. The boiler is fired with forest residue, recycled wood and peat. About 310,000 tonnes of biomass are burned at the site each year. For the most part, this is waste from pulp and forest industries. To minimize transportation, the fuel is sourced from regional landowners within a 200 kilometers radius. Each component at the plant is optimized to extract maximum energy, which is why essentially all energy contained in the fuel is utilized.
The group was guided by Lennart Friberg of Kraftringen, who enthusiastically shared his insight and experience into how the boiler of the production plant works. Here water is boiled to produce steam at 540°C. The steam drives the turbine that, via a generator, produces electricity. The steam is then cooled via condensers and the remaining thermal energy is fed into the district heating network.
“District heating is climate smart”, Lennart Friberg explains,”It makes it possible to use resources that would otherwise have gone to waste”.
The new biomass facilities were not the only technical attraction. On the way to Örtoftaverket the CITyFiED team passed a newly built facility for synchronous light based research, called MAX IV, where Kraftringen delivers both district heating and cooling to the laboratory. The research conducted here needs a lot of energy to accelerate electrons to a very high speed, so the cooling of equipment is critical. The waste heat produced in the cooling process is utilized in Kraftringens district heating system, enough to keep 1,800 households warm during a cold winter.
Kraftringen production of sustainable district heating and electricity gave an impressive account of minimized energy loss and continuously reduced emissions. No later than year 2020, all Kraftringen’s production of district heating is planned to be totally fossil free. With the realization of Örtoftaverket and the utilization of waste heat from research facilities and industries in the region,Kraftringen are well on their way to reaching this goal.
The visit gave the CITyFiED consortium a detailed insight into the scope, application and potential impact of efficient district heating and cooling using a range of biomass fuels. As work ramps up in demonstration sites and CITyFiED community of interest cities, the project will surely look forward to reflecting this in forthcoming webinars and ongoing work.
Hanna Holm, Kraftringen team
October 23rd, 2015