The Oitis complex consisting of 12 onshore wind farms is under construction in the states of Piauí and Bahia in Brazil. The wind farms will have a total generation capacity of 566.5MW.

The wind farms are being built by Força Eólica do Brasil, a subsidiary of Brazilian energy utility company Neoenergia, which is part of Spanish company Iberdrola.

Construction on the wind power complex started in November 2020, after it was approved in September 2019. The complex will be built with an estimated total investment of £412.2m ($506.5m)

Foundations for the wind turbines of the complex were completed in December 2021 and the operational tests for the first seven turbines of the Oitis complex were commenced in June 2022. The complex is expected to become fully operational in the second half of the same year.

At full capacity, the Oitis onshore wind farm complex is anticipated to supply electricity to around four million people. In addition, the facility will be able to offset 1.2 million tonnes of CO2 emissions over 20 years.

The electricity produced at the wind complex will primarily be used for trading in the Free Contracting Environment (FCE). The remaining power will be sold in the regulated energy market.

Location and site details

The Oitis onshore wind farm complex will be located in the Dom Inocêncio municipality in the state of Piauí and the municipality of Casa Nova in Bahia, northeast Brazil.

The complex will cover a total area of 2.1 million m2, with two of the 12 wind farms to be installed in Bahia and the remaining 10 in Piauí.

Oitis onshore wind farm complex details

The Oitis onshore wind power complex development will include the construction of Oitis 1 2, 3, 4, 5, 6, 7, 8, 9, 10, 21 and 22 wind farms.

The complex will comprise a total of 103 turbines with a capacity of 5.5MW each. The turbines will be of GE 158 model with 77.4m long blades. Designed with a rotor diameter of 158m, the turbine model belongs to GE’s Cypress onshore wind turbine platform that was launched in 2017.

With around 125m in height, each turbine will be installed on foundations consisting of a 79-tonne steel and concrete frame. Manufactured in Camaçari, Bahia, the nacelles will be 14m long and weigh 75.4 tonnes.

The project will also comprise the construction of a 500kV substation and approximately 70km transmission line to connect the new wind complex to an existing substation in the state of Piauí. The Oitis substation will consist of three 230MVA-capacity transformers.

Power purchase agreement

Neoenergia completed the sale of 67.6% of the electricity to be produced by the Oitis wind farms, as of June 2022.

Oitis 1 and 8 wind farms received guarantees for the 30% of the clean energy to be generated by them in the auction conducted by the Brazilian National Electric Energy Agency (Aneel) in June 2019.

Power evacuation

The electricity generated by the Oitis onshore wind farm complex will be evacuated into the National Interconnected System (SIN) through the Queimada Nova II substation in Piauí.

The wind complex will be connected to the electrical system via the new Oitis substation and a 500kV transmission line.

Project financing

Neoenergia secured £171.8m ($211.3m) funding from the European Investment Bank (EIB) to support its renewable energy projects, including the Oitis wind farms, in northeast Brazil in March 2022.

Contractors involved

GE was contracted to supply its Cypress platform turbines for the Oitis onshore wind farm complex.

DESEK was engaged to carry out the concrete dosage study and thermal studies of the wind turbine base for the project.