New Development

First turbine at Iberdrola’s Alto Tâmega Hydroelectric Plant connected to Portuguese grid

First turbine at Iberdrola’s Alto Tâmega Hydroelectric Plant connected to Portuguese grid
(Image credit: Iberdrola)

Iberdrola has taken another step toward full commissioning of the Tâmega Hydroelectric Complex by connecting one of the two turbine-generator units of the Alto Tâmega Hydroelectric Plant to the electric grid in Portugal.

The Tâmega Hydroelectric Complex is made up of three power stations: 160 MW Alto Tâmega Hydroelectric Power Station, 880 MW Gouvães Pumped Storage Power Station and 118 MW Daivões Power Station. The last two have been in operation since 2022.

The Alto Tâmega Power Station is located at the foot of Alto Tâmega Dam, a large double-curved vault dam, 105 m high, with 220,000 m3 of concrete and a crown length of 335 m, which has become the fifth highest dam in Portugal.

Now that the first turbine has been connected to the grid, the second will follow in February 2024. By the end of March 2024, this plant will be in commercial operation and the entire Tâmega Hydroelectric Complex will be operating with a total installed capacity of 1,158 MW.

Rafael Chacon Llorente, Tâmega project director, commented: “In a context where storage is key to enabling a decarbonized electricity system, maximizing the production of renewable energy and guaranteeing its integration into the system, the Tâmega Hydroelectric Complex has enabled Portugal to increase its hydroelectric storage capacity by 33%, representing an increase of more than 60% in the volume of energy stored by pumping in 2023 compared to 2021.”

Because hydroelectric storage is currently the only technology capable of storing electricity massively and efficiently, this complex can make the most of the energy generated by the wind and sun, making up for the periods when the sun doesn’t shine and the wind doesn’t blow.

Portugal gets more than 60% of its electricity from renewable sources and has the objective of reaching 85% by 2030. With the growth of renewables, the output of wind and solar power stations increasingly exceeds the system’s needs. Because it cannot be consumed or managed by the system, it would be lost if it weren’t stored by pumping water, particularly in the Gouvães reservoir.

The Tâmega Hydroelectric Complex is one of the largest energy initiatives in Portugal’s history, involving a total investment of more than €1.5 billion and an installed capacity of 1,158 MW and an energy reserve of 40 million kWh.