Duke Energy Renewables
Duke Energy Renewables, part of Duke Energy’s commercial portfolio, constructed the Los Vientos wind farm in Texas, US. Undertaken in five phases, the project involved the installation of approximately 910MW of renewable energy.
With a combined output of 402MW, the Los Vientos I and II wind farms began commercial operation in December 2012. The 200MW third phase started operations on 13 May 2015.
The 200MW fourth phase of the Los Vientos wind farm came online in August 2016, while the 110MW fifth phase became operational in December 2015.
Los Vientos wind farm location and make-up
Alamo is a 400MW solar photovoltaic (PV) power plant being constructed at different locations in San Antonio, Texas.
The 200MW Los Vientos 1 wind farm is spread over an area of approximately 30,000 acres of leased farmland. It consists of 87 Siemens SWT-2.3-108 turbines, each with a rotor diameter of 108m, which generate electricity sufficient to power approximately 60,000 homes.
Each wind turbine is supported by a foundation built of 680 cubic yards of concrete and 69t of steel reinforcement.
Los Vientos II is a 202MW wind farm consisting of 84 Mitsubishi Heavy Industry (MHI) MWT 102 wind turbines, each with a nominal capacity of 2.4MW. It produces enough power for approximately 60,000 homes.
Each MWT 102 wind turbine has a hub height of 295ft and rotor diameter of 334ft. The wind turbine foundations are made of more than 680 cubic yards of concrete and 66t of steel reinforcement.
The two wind farms produce 400MW of emission-free electricity, which is enough to collectively power approximately 120,000 homes.
The 200MW Los Vientos III comprises 100 Vestas V110-2.0 MW turbines. The wind farm, along with the under-construction IV (fourth) phase, is located approximately 100 miles west of Brownsville near Rio Grande City in Starr County.
The Vestas V110-2.0MW turbine has a rotor diameter of 110m and a swept area of 9,503m². The turbine tower is made up of tubular steel and comes with a hub height ranging between 95m and 125m. It operates at a rated wind speed of 11.5m/s.
Duke Energy also constructed the 110MW Los Vientos V, which includes 55 Vestas 2MW wind turbines. The plant is estimated to produce emission-free electricity sufficient to power approximately 33,000 homes.
Financing of Los Vientos I and II projects
North American Development Bank (NADB) provided a $220m loan for the construction of Los Vientos I and Los Vientos II wind farms.
Power generated by Los Vientos I and II is transmitted to the respective electrical substations. Voltage is hiked to 138kV at the substations and delivered to the Rio Hondo substation on the Electric Reliability Council of Texas (ERCOT) grid.
Offtake of electricity generated by the Los Vientos wind farms
Electricity generated by the Los Vientos I is purchased by CPS Energy under a 25-year power purchase agreement (PPA).
Austin Energy, one of the biggest publicly-owned energy utilities in the US, purchases the electricity produced by Los Vientos II. It also purchases the output and the associated renewable energy credits generated by Los Vientos III and IV under a 25-year off-take contract.
Power generated by the fifth phase is sold to Garland Power & Light, Greenville Electric Utility System and Bryan Texas Utilities (BTU) under separate 25-year power purchase agreements.
Contractors involved with the development of Los Vientos wind farms
Siemens is the supplier of 87 2.3MW wind turbines for the Los Vientos I wind farm, while MHI supplied 84 turbines of 2.4MW each for Los Vientos II.
Vestas was awarded the contract for the supply of 200 V110-2.0MW wind turbines for the Los Vientos III and IV wind farms. The contractual scope also includes a three-year operations and maintenance agreement for the projects. Vestas also supplied 55 wind turbines with a capacity of 2MW each for the Los Vientos V.
Wanzek Construction built the Los Vientos I, II and III wind farms. The third phase was constructed with development support from Amshore US Wind.