The project, named Desert Wind Power for the flat, agricultural region where it would be located, was proposed by Portland, Oregon-based Iberdrola Renewables Inc.
A 300-megawatt wind farm would be enough to power between 55,000 to 70,000 North Carolina homes with electricity.
Iberdrola has built more than 40 large U.S. wind farms over the past decade and coastal North Carolina is considered one of the choicest locations for wind turbines along the U.S. East Coast.
Iberdrola is considering other parts of the state for development potential if it can successfully develop the Desert Wind site.
"We believe this is a great site for a wind power project." Iberdrola Renewables spokesman Paul Copleman said.
"The fundamentals of any wind farm boil down to a strong and steady wind resource, access to transmission and a supportive community and we have all of those at this location," Copleman told Reuters.
The approval of the project by the North Carolina Utilities Commission is the first of several regulatory steps that must be cleared before construction, targeted for late 2011, can get under way.
Among other issues, Iberdrola will have to assure authorities that the 150 wind turbines that would be erected as part of the facility do not interfere with wildlife habitats, bird migration patterns or military flight routes.
The project could potentially benefit from a federal cash grant that would cover 30 percent of the cost, Copleman said.
Copleman said the estimated $600 million price tag for the North Carolina project was based on an industry average for the cost of developing and funding wind farms. That average works out to about $2 million spent for every megawatt of installed capacity.
"Given that our plans are for a 300-megawatt project that translates into a roughly $600 million investment on our behalf. But we consider the actual investment level proprietary information," Copleman said.
Desert Wind would sell power to electric utilities that are required to use green energy to meet state requirements for including more renewables in their energy mix.