The wind farm began operations in 2009. Credit: Fredlyfish4 / Wiki Commons.

Roscoe wind farm (RWF) is the largest onshore wind farm in the world. It is located 45 miles south-west of Abilene in Texas, US. Owned by RWE, it is one of the biggest wind farms in the world.

With an installed capacity of 781.5MW, RWF exceeds the capacity of the previously largest Horse Hollow Wind Energy Center (735.5MW) located in Taylor and Nolan counties southwest of Abilene.

Constructed by Germany-based E.ON Climate and Renewables (EC&R), the plant is located in 100,000 acres of land, primarily used for cotton farming, stretching into the three counties of Mitchell, Nolan and Scurry. The site is leased from dryland cotton farmers.

The construction on the wind farm began in May 2007 and it has been operational since October 2009. The Roscoe wind complex provides the community with 70 full-time working positions.

In October 2019, E.ON transferred its EC&R business to RWE, providing the latter with the ownership of multiple renewable energy assets, including Roscoe wind farm.

Roscoe wind farm construction

The Roscoe wind farm project was built in four phases. Of its total installed capacity of 781.5MW, approximately 209MW and 126.5MW are generated in the phase I and phase II units respectively. Phase III and phase IV together generate 446MW.

"Roscoe wind farm (RWF) is the largest onshore wind farm in the world."

The construction work was carried out by leading renewable energy developer and operator E.ON Climate and Renewables. It is the third wind farm project carried out by Airtricity in the state of Texas.

The Roscoe wind complex opened in February 2008 upon the commissioning of phase I. Phases II and III went live in March 2008 and March 2009 respectively. The operations of the first two phases began in September 2008.

Phase IV was completed in October 2009, opening for operations the same month, along with phase III.

Roscoe wind farm details

The wind farm employs 627 turbines, including 55 Seimens 2.3 MW turbines, 406 Mitsubishi 1 MW turbines and 166 GE 1.5MW turbines. From the start of the wind farm’s construction, a turbine was installed at the farm every day until completion.

The turbines installed at the farm range in between 350ft and 415ft tall, and stand 900ft apart. Out of the total number of turbines employed, 209 were the Mitsubishi 1000A model with a rated output of 1.0MW.

Power distribution from Roscoe wind farm

The power generated by the wind farm under phase I will be supplied to TXU Corporation’s subsidiary TXU Wholesale, under a five-year sales contract. The entire complex is capable of supplying power to 265,000 homes, while the power generated in its first two phases was distributed to 100,000 homes.

Approximately 375,000t of greenhouse gas emissions will be saved each year through the use of the wind farm when compared with plants that generate fossil fuels.

Roscoe wind farm financing

The first phase of the project involved an investment of $300m. Approximately $1bn was invested in all four phases in total.

GE Energy Financial Services invested 50% of the structured equity in the 209MW first phase, along with a subsidiary of Wachovia Corporation. The Roscoe wind farm is the second project that was carried out jointly by E.ON Climate and Renewables and GE Energy Financial Services in West Texas. The remaining 50% of the equity was held by E.ON Climate and Renewables.

Texas power market

Texas has an installed capacity of 7,907MW in wind power generation. It is the leading state in the US in renewable energy development with the highest wind generation capacity in the country.

The American Wind Energy Association said that approximately 2,800MW of new generating capacity was installed in the US during the first quarter of 2009.

E.ON Climate & Renewables operates six wind farms in the US, five of which are in Texas. RWF hopes to accomplish an additional power generation of 5,000MW from renewables sources in Texas by 2015.