Estonia had obligation to EU to use 5.1% of renewable power (from the total consumption) by the end of 2010. This obligation could be reached mainly by introduction of new co-generation power plants on the basis of biomass (Tallinn, Tartu, Pärnu), with expanding power production from the wind, but also by co-firing Estonian oil shale (OS) and biomass (BM) at large oil shale power plants in Narva region. The essential precondition of co-firing of BM and OS in boilers of Baltic and Estonian power station is availability of sufficient quantities of bio fuels in the neighbourhood. In Estonian conditions the most promising biomass for co-firing is wood fuel, but due to availability of abandoned agricultural lands in the North-Eastern part of Estonia short-rotation forestry (willow, grey alder etc.) or plantations of energy crops and wetland plants may play considerable role, too. During 2009/2010 about 200000 tons of wood chips and about 10 million tons of OS were used for power production in Narva power plants already [1]. In the context of OS and BM co-firing at large OS boilers two aspects should be analysed. The first question is related to possible technical problems of co-firing, and the second one concerns BM resources available in the North-East region of Estonia. These two problems are analysed in the paper. It was concluded that co-firing of pulverized OS and BM (up to BM content in the blend of 15% by mass) does not have any considerable negative effect on the normal operation of boiler while reducing environmental emissions. Wood and other BM resources will cover relevant need for BM at the distance of 100 km from the power plants.
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