This research utilizes solar thermal energy that absorbed by the outer wall of the building which facing north. The heat energy is converted into electrical energy using a thermoelectric generator type TEC 12706. To maintain the cold side area of TEC 12706 heatsinks are circulated with circulating water cooling fluid with a discharge of 1.8 lpm and the temperature is not more than 3oC. The study was conducted with a simulation tool composed of several materials such as glass, aluminum, styrofoam and heatsink. The test is conducted from 06.00 WIB until 18.00 WIB for 3 days. The parameters measured are light intensity, wind speed, water flow, temperature, electric voltage and electric current contained in the test equipment. The research results get a maximum output power of 0.0024 W, thermoelectric efficiency and system efficiency.