Technological developments on energy savings are caused by increasing demand for energy use from year to year. This is done to avoid an energy crisis. The energy crisis is a problem that is being faced because of the depletion of fossil energy. To restore fossil energy can require natural processes in a long time. With the limited availability of fossil energy, it is very necessary to develop alternative energy sources that are friendly to the environment, one of which is wind energy. Indonesia is an archipelago, so the wind speed in Indonesia is relatively low, then in this study can be overcome using a vertical axis wind turbine (VAWT). This research was conducted to find out power of Coefficient, type speed ratio in the variation of wind speed in the turbine. This study uses a wind power design with a vertical axis. Blades are used from modified NACA 0018 airfoil. Research result taken at the time of testing is with wind speeds ranging from 3 m / s to 6,1 m/s which measures the capacity of electric power produced by turbines with a load of 10 watts. The results of this study are the minimum actual power of the turbine 2.881 Watt with TSR 0.4 and Cp 0.18 at wind speed 3 m/s, and the maximum power obtained at a speed of 6,1m/s that is equal to 14.62 Watt with a TSR of 0.25 and Cp of 0.29.