In this study, experiments were conducted to maintain a comfortable indoor temperature, to reduce energy consumed by air conditioning, and to generate green electricity. It used a phase change material (PCM) and thermoelectric systems to construct facade models made of reinforced concrete (RC). It simulated solar heating, and measured temperature differences between specimens and output voltage during simulation. Experimental results were analyzed using robust regression. The maximum temperature difference between the two wall surfaces was 21%. The temperature of the heated PCM-altered wall was 19.3% lower than that of a conventional RC wall after 8 h. The highest output voltage was 200 mV. The findings of this study are expected to improve building energy use, and thus to contribute to environmental sustainability.