Economic and Technical Performance Assessment of a Thermal Energy Storage System for Ancillary Services

Abstract

Increasing renewables in energy mix results in lower emissions but also increased fluctuations in the electricity grid. Current thermal energy conversion-based systems will stay as main electricity generation in the grid, and they will support base loads of the system. Whether these systems are fossil or geothermal sourced they need adaptive technologies to harmonize with the changing network. This study aims to investigate feasibility and performance to satisfy response demands for a proposed thermal energy storage system connected to feed stream of thermal power generation to support ancillary services in a case study in Turkey. Tin is selected as the phase change material for its good inductive properties. It is demonstrated numerically that the evaluated heat storage tank, filled with tin, provides adequate time for thermal discharging within time limits to benefit from hourly ancillary power market. Using hourly pricing data for entire 2020, it is found that proposed system shows better economic performance than investment requirement of ROI over 11% as stated in various literature for renewable energy systems. Analysis of system economic performance shows a ROI of 16% and NPV is 17.8% higher than required investment.