This paper presents an ongoing research project on solar combisystems for the Nordic and Baltic countries of Europe. The aim of the project is to develop competitive solar heating systems, which are attractive to buyers and to educate experts in the solar heating field. The participants of the project, which is financed by Nordic Energy Research and the participants themselves, are the universities: Technical University of Denmark, Dalarna University, University of Oslo, Riga Technical University and Lund Institute of Technology, as well as the companies: Metro Therm A/S (Denmark), Velux A/S (Denmark), Solentek AB (Sweden), SolarNor (Norway) and SIA Grandeg (Latvia). In Denmark and Norway the research and development focus is on solar heating/natural gas systems and in Sweden and Latvia the focus is on solar heating/pellet systems. Additionally, Lund Institute of Technology and University of Oslo are studying solar collectors of various types being integrated into the building. The paper focuses on the Latvian situation. Different barriers to solar energy use in Latvia were identified during the inception phase as well as the market potential for solar combisystem. The paper illustrates the most significant activities that were carried out until now in Latvia, in particular the development of a new biomass-solar laboratory and the developed prototype of solar combisystem, which will be installed in different a demonstration projects.