Tâmega: one of the most important initiatives in the energy sector in Portuguese history

The project entails an investment of more than €1,500 million to build three new plants (Gouvães, Daivões and Alto Tâmega) on the Tâmega River.

Tamega infraestructure, main project data.#RRSSTamega infraestructure, main project data.

This Iberdrola's flagship project involves the construction of three new power plants: Gouvães, Daivões and Alto Tâmega, which will be erected over the Tâmega River, a tributary of the Duero in the north of Portugal, close to Oporto. The European Investment Bank (EIB) finances this development with 650 million euros, which will involve a total investment of more than 1.5 billion euros. The three power plants will have a total installed capacity of 1,158 MW and will be capable of producing 1,766 GWh per year.

The project also will promote to the economic activity and the employment in the region, because it is estimated that up to 13,500 jobs will be generated, including direct and indirect jobs, during the entire construction phase and several hundred people will be hired in operational phase.

Iberdrola starts the assembly of the first turbine for the hydroelectric power plant at Gouvães. This plant, where works have just begun on installing the suction pipe for the turbine in group 4, will be an underground plant equipped with four reversible pump turbines, generating a total power of 880 MW.

The Gouvães quarry is already operational and producing the aggregates that will be exclusively used in the concrete of the Tâmega Hydroelectric Complex, including the concrete used to build the dams. This quarry is expected to produce more than 2 million tons of aggregates, the equivalent to the weight of 5,000 fully equipped Boeing 747s carrying passengers.

The company also has started the concreting works for the Daivões Dam, one of the power plants comprising the Tâmega Hydroelectric Complex. The construction of this dam — which will take just over a year — will involve the production of some  242,000 m3 of concrete. This will be manufactured in a concrete batching plant with a production capacity of 200 m3/h, equipped with two cable cranes, systems to transport and place the concrete via suspended cables supported at either end at height. The concreting works began after the foundations for the dam had been excavated and these works, which lasted more than 13 months, involved the removal of around 136,000 m3 of rock.

It is expected that Gouvâes will start operating in 2021, Daivões in 2022 and Alto Tâmega in 2023.

This infrastructure is another form of evidence of Iberdrola's permanent commitment to clean energy generation technologies, as well as a very important contribution to the Iberian electricity market.

Hydroelectric power: renewable and autochthonous

The company is leader in energy storage with an installed power of 4,400 MW using pumping technology, the current most efficient storage method, since it generates no atmospheric contaminating emissions and its performance is much higher than that of the best storage banks in the market.

Hydroelectric power plants like the Tâmega are a safeguard for the electrical system. The largest facility of this kind in Europe is the Cortes-La Muela complex in Valencia. Another example is the Cruachan station, located near Oban, in the United Kingdom.


  • Tâmega Project

    This Plan, developed in the context of the Tâmega project and signed by the different Municipal Chambers participating in it, includes a record figure of over 50 million euros for the economic, social and cultural development of the Alto Tâmega region.

    The purpose of the program is to contribute to the development of the region and improve the standard of living of the population — it's estimated that 3,500 direct and 10,000 indirect jobs will be generated during the execution of the complex — as well as to preserve the environment where the project will be carried out, from an environmental point of view. Planned actions will be carried out in the municipalities of Ribeira de Pena, Vila Pouca de Aguiar, Cabeceiras de Basto, Boticas, Chaves, Valpaços and Montalegre.

    An example is the region of Boticas, in which Iberdrola has participated in the development of the Boticas, Nature and Biodiversity park, building accommodation for visitors and encouraging actions for the compensation of the natural environment's flora and fauna.

    Boticas, Nature and Biodiversity park.

    Boticas, Nature and Biodiversity park.

    In addition to these projects, Iberdrola is funding other activities, such as the improvement of the public sewer and water supply networks, upgrading and optimising sporting facilities, upgrading the equipment used by fire brigades, new recreational areas, etc. In addition, it has co-funded the construction of the new and flagship facilities and installations in the area, such as the Alvão Village Campsite, the Pedras Salgadas Horse Riding Centre or the Educational Health Resort in Vidago.

    With this type of aid, Iberdrola consolidates its commitment to sustainability and social responsibility.

  • Tresminas Roman gold Mining Site

    Tresminas Mine Complex, Portugal. Video voice transcription (Spanish version) [PDF]

    As part of the construction of the large Tâmega Hydroelectric Complex, Iberdrola has also promoted a visit to the Tresminas Roman gold Mining Site, a project that is part of the compensation actions carried out by the company pursuant to what is established in the Environmental Impact Statement. 

    With the investment of 1.84 million Euros in the Tresminas Mine Complex, Iberdrola is demonstrating its commitment to the economic, social, cultural and environmental development of the communities where it operates. The company is collaborating with the Vila Pouca de Aguiar Town Council and the North Portugal Regional Department of Culture in the historical, archaeological and heritage enhancement of the region. This investment started in 2016 and is expected to continue until 2023.

    The company has allocated, between 2016 and the end of 2018, around 850,000 Euros which, throughout this year, will be invested as follows:

    • The funding of the technical equipment.
    • The continuation of the historical geological and fauna and flora studies in Tresminas.
    • The acquisition of equipment for visits to inverted cone pits and mine-shafts, and for their maintenance and/or clearance.
    • The construction of the support building and structures and equipment to support movement in the inverted cone pits and mine-shafts.


    The Tresminas Roman Mine Complex was, during the Roman Era, one of the main gold explorations in the primary deposits of the conventus bracaraugustanus and one of the most significant ones in the Northwest of the Peninsula: it is estimated that between the I and III centuries A.D. around 25 tonnes of pure gold were obtained from Tresminas, which involved the ejection of millions of tonnes of rock excavating open inverted cone pit mines.

    Iberdrola is committed with this initiative to the preservation of local and national heritage in the region of Tresminas, as well as to make the archaeological and historical importance of this mine complex well known and to boost tourism in the area.

    The investment made by the company allows a set of actions to be carried out that benefit the Tresminas Mine Complex, facilitating its future recognition as an Archaeological Park, which will safeguard the materials associated with Roman mining and the landscaping of the area.

    Tresminas is part of the municipality of Vila Pouca de Aguiar's strategic pillars in terms of cultural tourism.  The efforts made over the last few months, both at local and regional level, following the enhancement of the heritage and tourism value of Tresminas, have already resulted in an increase in the number of visitors to the region.


    In fact, these results have been supported by activities in cross-border partnership with Las Médulas, UNESCO World Heritage Site since 1997 and one of the most important and well-known Roman mines, in the El Bierzo region in Spain. The candidature is made jointly, in a common cultural project, which aims to enhance the value of the Iberian Peninsula's Roman mining legacy. In 2017, this cooperation protocol between the Municipality of Vila Pouca de Aguiar and the Las Médulas Foundation was supported by organisations such as the Direção Regional de Cultura do Norte and the Castilla y León regional government's General Directorate of Cultural Heritage. This alliance aims to further strengthen the candidature of this area of Portugal as a UNESCO World Heritage Site.