Technical and Economic Analysis of Thermal Energy Storage in the Biomass CHP Plants with ORC Technology


The investments in units of electricity production from the renewable energy sources have an increasing trend in the European Union countries. The production of elec-tricity from renewable energy sources and cogeneration is promoted by various support mechanisms. The quota obli-gation system and tradable green certificates was imple-mented in Romania. In the case of biomass, the support scheme provides two green certificates for each MWh deli-vered to the public electricity network and additional one green certificate if the electricity is produced in high effi-ciency cogeneration. For cogeneration plants, demand for useful heat is the essential condition in the qualification of electricity production in high efficiency cogeneration. A solution to provide the demand for useful heat and compen-sation of load variations over time is the storage of thermal energy. The paper presents the technical and economic analysis of the heat storage systems integration for a coge-neration unit with organic Rankine cycle (ORC) and bio-mass fuel. The use of thermal energy storage in the heating network of the ORC unit may allow connection of new con-sumers without disrupting the operation of current consum-ers. The increased heat consumption delivered of the coge-neration unit will allow the qualify for a larger amount of electricity in high efficiency cogeneration. images