Technology

Hydroelectric energy plays an important role in energy supply in Spain. It has a long history that has culminated in the development of a technologically mature and highly consolidated sector. The sector has grown in recent decades, although its contribution to total electricity output has gradually fallen.  

Had hydroelectric power not existed, experts say we would have had to invent it because no other technology offers the same ease of use and rapid response that this technology boasts to generate electricity.  

All hydroelectric power stations use the energy harnessed in water to move a turbine. However, there tend to be three types of plant depending on the design: “run-of-river” plants, plants at the foot of a dam, and reversible plants. This latter type of plants provides one of the great advantages of hydropower:   its energy storage capability. Reversible dams can pump water up to another reservoir located at a higher point during periods of low demand. This water can then be used to drive the turbine during peak demand, which is when it is most needed. The development of this form of hydropower enables the share of renewables (wind for example) to be increased without threatening the stability of the electricity system.  

In 2009, Spain had 13,521 MW of hydropower in plants of over 50 MW. A further 3,077 MW of capacity was installed in plants ranging from 10 to 50 MW, while 1,920 MW was installed in small hydroelectric plants with a capacity of less than 10 MW.  

Spain has companies that manufacture equipment for this type of power stations. New advances are being made in turbine design to generate power from small heads, control systems, etc. which will boost plant performance and enable them to adapt to an increasingly scarce and variable resource. In the future, efforts will focus on new installations that use existing hydraulic infrastructures, and on developing a fleet   of pure and mixed pumping stations that help in the management of the Spanish electricity system.

• Spain has the third   largest installed small hydro capacity in Europe after Italy and France, and is fourth in terms of plants with a capacity of over 10 MW.
• The objective of the 2005- 2010 Renewable Energies Plan for small hydroelectric plants of less than 10 MW is 2,199 MW.
• Technically usable hydroelectric capacity in Spain has been fixed at 65,600 GWh/ year. Approximately half of this capacity is being used.  
• The hydroelectric sector has achieved a high level  of technological efficiency as a result of 150 years of development.