Feasibility of small-size biomass-fueled Hirn-cycle cogeneration plants

Biomass utilization seems to be the easiest way to increase the exploitation of renewable energy sources for small and medium scale energy production. In particular, ligneous biomass, thanks to its availability, appears to be the most suitable for cogeneration applications. Among the several technologies available for energy conversion, the most frequently utilized system to generate electric power is still a process based on a Rankine or Hirn cycle with water as a working fluid. This solution seems quite interesting particularly for small size cogeneration plants because of its availability on the market and the analogy with typical applications involving fossil fuels. Many investors (e.g. Energy Service Companies, ESCOs) might be interested in the installation of this type of cogeneration plants in order to reduce the environmental impact of the system and therefore to benefit from governmental incentives. In order to assess the feasibility of this type of plants, it is important to investigate the possible thermodynamic, economic and technologic constraints. An analysis of these factors has been carried out in the present study.