In big cities, intensive solar radiation in summers increases the surface temperature of pavements and building roofs to around 60 °C and results in a significant increase in the ambient temperature. It is desirable to capture outdoor thermal energy and convert it into electrical energy. Energy harvesting experiments based on the thermoelectric behavior of carbon fiber reinforced cement composites (CFRC) have been performed for the first time under simulated solar irradiation. The thermoelectric figure of merit (1.334 × 10⁻⁷) was determined at room temperature for CFRC with a carbon fiber content of 1.0 weight percent. A slab sample was used to estimate the energy harvesting quality of CFRC at a temperature difference of about 60 °C. 4–5 μw of power was obtained from a one square meter CFRC slab with a thickness of 20 mm. The harvested energy of this one square meter CFRC slab reached a maximum of 8.4 × 10⁻⁶ J over 420 minutes of irradiation, while its surface temperature increased quickly.

The thermoelectric properties of perovskite CaMnO ₃ with A-site defects were synergistically optimized and the lowest κ _t value of 0.94 W m ⁻¹ K ⁻¹ was found at 800 °C.