In this study, a novel electrochemical device operating based on the thermally regenerative electrochemical cycle (TREC) and including two TREC cells: a hot cell and a cold cell, is proposed to be utilized in buildings to harvest solar energy. The hot cell is heated by solar energy, and should be in direct contact with a hot part of a building such as iron roof and window, while the cold cell should be in direct contact with a heat sink located in a shaded position of the building. The proposed device is first analyzed in detail to provide theoretical concepts. The device has been also constructed and installed in a building, so that, its hot cell is in direct contact with the black iron roof of the building, and its cold cell equipped with a heat sink has been positioned in the shade of the roof. Experimental verifications are given that verify the proposed TREC based device efficiently converts solar heat into electric power ranging up to 54.5 W. To substantiate the novelty and contribution of this research work, the daily power production and all the parameters of the proposed TREC based device which converts solar heat into electric power are compared to those of a commercial PV module KC200GT which converts solar irradiance. The comparison explicitly demonstrates that the economic factor (Cost per kWh) of the TREC based device (317.16 Euro) is slightly more than that of the PV module (315.13 Euro), but instead, it has lower weight and smaller size. Thus, there is technical and economic justification for utilizing the proposed TREC based device. (C) 2018 Elsevier Ltd. All rights reserved.