Highly-efficient biomass CHP plants by handling ash-related problems


Heating and cooling are responsible for almost half of EU’s final energy demand. Biomass is currently responsible for more than 90 % of all renewable heat. The goal of biomass-based technologies is to increase its share in the heat market in Europe from 11 % in 2007 to about 25 % in 2020. Combined Heat and Power (CHP) from biomass is a suitable technology for medium- and large-scale units where many utility and industrial applications can be found in Scandinavia.

The main challenge for efficient CHP and high temperature steam production from biomass are ash-related problems. Corrosion due to the difficult ash composition of biomass limits both steam temperature and efficiency. By solving these issues, large-scale boilers offer a huge potential for efficiency increase and emission reduction during CHP generation at cost competitive and environmental friendly conditions.


In order to reach these goals and to enable a secure and almost carbon neutral heat and power generation, several measures have to be undertaken. The main objectives and goals of the Biofficiency project are:

  • Develop next generation, biomass-fired CHP plant with elevated steam temperatures up to 600 °C at medium to large scale (10 to 200 MWth).
  • Increase efficiency of CHP plants by elevated steam temperatures through solving and understanding of ash-related problems – slagging, fouling and corrosion.
  • Reduce emissions – i.e. CO2, particulates, CO, NOx, and SO2 – by efficiency gain, reduction of impurities and by intelligent plant design.
  • Widen the feedstocks for pulverised fuel (PF) and fluidised bed (FB) power plants using pretreatment methods with focus on the reduction of harmful, inorganic elements: chlorine, sulphur and alkali metals.
  • Widen ash utilisation and nutrient recirculation, by detailed ash analysis in terms of chemistry and physical properties. explore new ideas to the European technical regulation for future biomass ash usage.
  • Design of a reference CHP plant based on detailed measurement results and modelling studies.


The Biofficiency Project is receiving funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 727616.

Involved Partners


Lynn Hansen, Sebastian Fendt