Low-Cost Material for Sensible Heat Based Thermal Storage to be Used in Thermodynamic Solar Power Plants

Thermal storage is a key component for thermal solar power plants. Today, no technology and material meet all the desired technical, economical and environmental targets. Especially in the case of extended storage (some hours), thousands of tonnes of materials are concerned leading to high investment cost as well as high energy and CO₂ contents. In the present paper, an industrial ceramic made by vitrification of asbestos containing wastes is studied as a candidate to sensible heat storage material for both medium and high temperature solar power plants. The obtained stone-like material presents no hazard, no environmental impact, good thermophysical properties and a very low commercial cost (8 euros/t). Thanks to the vitrification process of the wastes, the obtained ceramic is very stable up to 1000°C and can be manufactured in a desired shape. Then, heat exchangers made of the storage material can be potentially realised and integrated in thermal processes.