Development of a High-Performance Concrete to Store Thermal Energy for Concentrating Solar Power Plants

Abstract

Researchers in their quest to find a suitable candidate material for solid sensible heat storage have identified concrete as an acceptable medium. However, at temperatures of 500°C and beyond the thermo-mechanical properties of ordinary concrete change significantly. This paper presents seven concrete mixtures of various material components and proportions that were developed and tested for resistance to temperatures up to 500°C. After exposure to 10 thermal cycles from ambient temperature to 500°C, six of the seven mixtures maintained in excess of 50% of their mechanical properties. This result is favorable for concrete to be used as a thermal energy storage medium. With concrete exhibiting acceptable mechanical and thermal properties at very high temperatures, the amount of energy stored per unit volume is increased, higher steam temperatures are available to facilitate power generation and the concrete can last for the design lifetime of the power generating system into which it is integrated.