1. Cracow University of Technology, Faculty of Environmental Engineeringand Energy, Warszawska 24, 31-155 Kraków, Poland
2. SINTEF Industry, P.O. Box 124 Blindern, N0314 Oslo, Norway
3. Norwegian University of Science and Technology, Department of Energyand Process Engineering, P.O. Box 8900, NO-7491 Trondheim, Norway