DENVER — Xcel Energy is continuing its aggressive expansion of renewables as part of the company’s power generation arsenal, with yesterday’s announcement that it has agreed to buy 250 megawatts from BP Wind Energy’s Cedar Creek II wind farm in Weld County. Construction of the new wind energy development is expected to begin this summer.

BP Wind Energy joined with Xcel’s Public Service Company of Colorado in making the news public on Wednesday. The wind farm is located aboutt 20 miles north of New Raymer, east of the existing 300-megawatt Cedar Creek I wind farm.

According to the companies, 20 miles of new overhead transmission lines will bring electrical output generated by the new turbines to the power grid.

Although the location is not far from a Vestas Wind Systems blade-manufacturing plant in Windsor, BP Wind Energy will use wind turbines manufactured outside of Colorado by GE and Nordex.

“Wherever possible we try to use local sources, but we already had contracts in place with GE and Nordex,” said BP Wind Energy spokeswoman Amanda Abbott.

She said BP is using Vestas turbines for wind farms in Texas and Indiana.

Roughly 250 workers are expected to be employed during construction of the wind farm, and once operational, about a dozen people will monitor and maintain the facility.

As the largest power supplier in Colorado, Xcel Energy is under the gun to meet the newX 30 percent renewable energy standard by 2020, upped from 20 percent by the legislature earlier this year.