This paper demonstrates the potential of a post-industrial ceramic commercially called Cofalit (R) as a promising, sustainable, and cheap filler material in a molten salt direct thermocline storage system. This ceramic, which comes from industrial treatment of asbestos containing waste, demonstrates relevant properties to store thermal energy by sensible heat up to 1100 degrees C and is very inexpensive. In the present study, the compatibility of this ceramic with two different molten salts-the conventional binary Solar salt and a promising ternary nitrate salt also called HITEC XL-is tested at medium temperature (500 degrees C) under static state. The objective is to develop a molten salt thermocline direct storage system using low-cost shaped ceramic as filler material. It should significantly decrease the cost of parabolic trough storage systems and simultaneously increase the efficiency of the plants by producing superheated steam at higher temperature. (c) 2013 Elsevier Ltd. All rights reserved.