Taiwan is an island which has very limited natural resources. In order to reduce the dependence on imported fossil fuel, Taiwan government invested a lot of resources to develop renewable energy technologies. The Renewable Energy Development Act of Taiwan is published in July 8, 2009. Although solar and wind power systems have been highly promoted in Taiwan, the Act has no amendment since it announced.

The growth of penetration of renewable energy generation will increase the affection of power quality of distribution system. In this paper, OpenDSS developed by EPRI is used to simulate the voltage profile for maximum allowable renewable energy power connected to the distribution feeder. The results show that if the sum of renewable power generations is greater than demand, the voltage alone the feeder could be greater than 2.5%, which does not comply with the voltage regulation rules for renewable energy generation of Taipower.