A low-cost and enhanced thermal properties composite material for sensible heat storage in solar thermal
energy storage applications is introduced. The proposed material is produced primarily for small scale solar
thermal applications. However, it can be utilized for large scale solar thermal plants. The material has the
advantages of high thermal conductivity and large energy storage density. The introduced material is
composed of a mixture of cement and cast-iron particles. To obtain an optimal mixture, different samples of
the material are prepared with different ratios of the cement-iron weights. The thermal conductivity of the
produced samples is measured by using the linear heat conduction method. The specific heat capacity of
the produced mixtures is calculated by using the Rule of the mixture. The obtained results show that the
introduced material has a significant enhancement in thermal conductivity. Where, thermal conductivity as
high as ~6.0 W/m.K and energy storage density as high as ~788 Joule/cm3
are achieved. The estimated
volume energy density is ~89% higher than that of water. The produced material has the advantage of high
energy volume density, being unhazardous, chemically stable, eco-friendly, easy to fabricate, and integrate
with solar thermal energy systems and is a low-cost material.