Heat Storage Combined with Biomass CHP under the National Support Policy. A Case Study of Estonia

Abstract

In spite of the progressions in heat storage systems for combined heat and power’ (CHP) plants performance, these innovations have not been implemented in CHP-based district heating (DH) systems in some of the countries where DH systems are still being developed. An examination of environmental and economic advantages that can be gained as a result of heat storage installation into the DH system are necessary to effectively popularise heat storage as a DH system-improvement technology. A real large-scale biomass CHP-based DH system is investigated in this case study. Scenarios for two kinds of support policies (feed-in premium for electricity generated by biomass CHP and energy-efficient biomass CHP) were analysed by changing the extent of the heat storage. The goal of this study was to assess the impact of the biomass CHP policy support instruments on the viability of integrating heat storage. Calculations demonstrate that fitting of heat storage combined with biomass CHP is less viable when all power generated by biomass CHP is subsidised.

Keywords

• accumulator tank
• district heating
• electricity market
• feed-in premium
• primary energy
• thermal energy storage