Back 01.09.2009

Gaia’s new study: Forest industry’s sludge and reject fractions have a strong bioenergy potential

Bioenergy can be successfully produced from forest industry’s low value side streams such as sludge and reject fractions, shows a new study carried out by Gaia.

According to the study, published today at Bio Energy 2009 Conference in Jyväskylä, Finland, especially production of biogas from sludge fractions seems encouraging. In Finland only, it could provide energy for 10 000 detached houses annually. The results of the study open up interesting possibilities for further business development, especially for small local bioenergy enterprises.

Gaia identified the most potential business concepts for upgrading forest industry´s less utilized side streams to value-added bioenergy products. From the initially selected side streams, deinking rejects and biosludge were selected for further analysis.

“Certain side stream fractions are left out of the main focus of the currently developed large scale biorefineries. For small and medium sized enterprises, these side streams provide business opportunities for developing tailored bioenergy products. Biogas produced from biosludge from pulp and paper mills provides an annual energy potential of 580 GWh in Finland. It corresponds to energy usage of 10 000 detached houses, which is an interesting business opportunity for small local bioenergy companies”, says Senior Consultant Tiina Pursula from Gaia.

The study was carried out by Gaia, a Finnish consultancy on sustainability, and commissioned by Joensuu Science Park Ltd and Jyväskylä Innovation Ltd. The study was part of the Forest Industry Future Competence Cluster under the Center of Expertise Programme OSKE. Companies representing pulp and paper industry and bioenergy were also involved in the project.

The study is part of Gaia’s extensive work on finding solutions to renewable energy and energy efficiency. Recently, Gaia has carried out various projects on bioenergy, such as strategic consulting (e.g. developing concepts for bioenergy business, promoting co-operation and business on bioenergy between China and Finland), international projects (e.g. utilization of mechanical forest industry by-products in Central America) and national projects (e.g. a study on Finnish know-how on bioenergy technology).


  • Juha Vanhanen, Managing Director, +358-50-564 1889,
  • Pasi Rinne, Chairman, +41-79-472 6909,

Information on Gaia’s projects on sustainable energy: