TOPEKA, Kan. (AP) -- Westar Energy plans to purchase 200 megawatts of electricity from a northern Oklahoma wind farm expected to begin operating in late 2016.

The Topeka-based utility announced Wednesday that it had reached a purchase agreement with Virginia-based Apex Clean Energy.

Westar already has about 700 megawatts of electricity from renewable resources.

Apex plans to start building the 18,000-acre wind farm in 2015. The site is about six miles south of Arkansas City, Kan., where city manager Nickolaus Hernandez says the project is expected to boost the local economy.

Westar is the largest electric utility in Kansas, with about 700,000 customers.