The changes in the domestic solid fuel market (including forecasted increases in the fuel prices) and the growing requirements related to actual environmental standards, result in increased interest in renewable energy sources, such as biomass, wind and solar energy. These sources will allow to achieve reduction in the CO2 emission, and consequently – avoid environmental costs after 2020. Therefore, the development of distributed energy systems, based on the use of biomass boilers, gas boilers and high efficiency combined heat and power units, will enable the fulfillment of current standards in the field of energy efficiency and emission of pollutants to the atmosphere. It should be emphasized that the actions taken to reduce emissions (e.g. anti-smog act) will contribute to reducing coal consumption in the municipal and housing sector (households, agriculture and other customers) in favor of biomass and other renewable energy sources. The article reviews selected biomass technologies: - fluidized, dust and grate boilers, - straw-fired boilers, - cogeneration systems powered by biomass, - torrefaction and biomass carbonisation. The mentioned technologies are characterized by a high potential of in the field of dynamic development and practical application in the coming years. Thus, they can improve difficult situation in the distributed energy sector with a capacity up to 50 MW.
Wood pellets, commonly referred to as biomass fuel, are increasingly used in heating and district heating in the European Union countries, including Poland. Their use in class 5 and/or Ecodesign boilers enables an individual consumer to use energy from renewable sources, reduce the environmental burden by reducing the emission of harmful compounds, and provides a sense of comfort by automating the boiler system. The article presents the current situation in the global wood pellet market, describes the basic quality standards applicable to this fuel during production, and indicates the difficulties in the implementation of programs co-financing the replacement of obsolete coal-fired boilers with automatic class 5 biomass-fired boilers. The research presented in this article is focused on the presence of contaminants in the DIN Plus, EN Plus, and A1 pellets, as well as in non-certified pellets. The analysis has shown that the use of wood pellets containing prohibited substances negatively affects boiler operation and contributes to the formation of slag and the emission of harmful compounds, making the discussed fuel non-ecological.