Equivalent households

A century of clean energy

A run-of-the-river hydroelectric plant with a capacity of 37 MW. It was built between 1912 and 1918 and has been conserved as an example of modernist industrial architecture.

The Seira Station, located in the town of the same name in Huesca province, is a 36.65 megawatt (MW) plant with three power sets. Of the run-of-the-river type, it can supply clean energy to around 23,000 homes.


Its distinguishing feature is its historical importance. It was built between 1912 and 1918 to supply power to Barcelona, the one with the highest voltage in Europe at the time. It was an engineering work of extraordinary importance when it was built. It has been restored to its original architecture, and is a magnificent example of an early-20th-century industrial complex.



  • Location: Seira. Huesca. Spain.
  • Capacity: 36.65 MW.
  • River basin: Ésera River.
  • Type: A run-of-the-river plant with a diversion dam.
  • Start-up: 1918.
  • Flow through the turbine: 28 m3/s.
  • Type of turbine: Francis (3).
  • Gross fall: 146.5 m.
  • Owner: ACCIONA.


  • An installation of historical interest, an outstanding example of early-20th-century hydraulic engineering. It played a major role in the economic development of the area and in the supply of power to industry in Catalonia.
  • Its interior and exterior design has been maintained in its original form as an example of modernist industrial architecture.
  • Despite its age, thanks to modern equipment it still produces energy to cover the demand from around 23,000 homes.

Key figures


megawatts (MW)


equivalent households

28 m3/s

Flow through the turbine


hydraulic groups

146.5 m

Net water fall


operating years


A century making electricity from water

In many respects, it is a living museum. The beauty of its architecture, and the antiquated machinery sparkling within its halls, are a delight to behold. But a century after construction, Seira hydroelectric power station is still generating clean energy...

More projects from ACCIONA

Discover all of our projects