One of the Canary Islands, El Hierro uses only water and wind to meet its electricity needs. A remarkable independent energy model which has become a world benchmark.
One of the Canary Islands, El Hierro is not only the smallest island in the Spanish archipelago but also the most innovative. Since 2014, it is the first island in the world to be completely electricity independent thanks to renewable energies.
Like all islands, El Hierro faces difficulties obtaining energy. The island must not only supply electricity to its 11,000 inhabitants and the many tourists who visit it, but also supply 4 seawater desalination plants. And since the island doesn’t have any water reserves and precipitation is very rare, water from the Atlantic Ocean is treated to provide the population with a supply of fresh water.
Prior to 2014, the island imported 6,000 tonnes of oil a year to meet its energy needs - an expensive solution that produced large amounts of CO2.
The only hydro-wind power station in the world
On June 27, 2014, El Hierro opened "Gorona del Viento", its hydro-wind power plant - a unique and innovative complex consisting of 5 wind turbines and 2 artificial reservoirs. At a height of 650 meters, these reservoirs can store 380,000 m3 of water.
As the archipelago is always swept by winds, wind turbines can run at full throttle most of the time, and are capable of generating 11.5 MW – more enough to meet the electricity needs of the island, which rarely exceed 8 MW.
The electricity surplus is used to transfer the water from the lower basin to the upper basin, using a pumping system. When the wind drops the water in the upper reservoir is released and as it falls it activates 4 hydraulic turbines which in turn produce electricity. Able to generate 11.3 MW, the turbines can easily take over from the wind when necessary.
El Hierro therefore manages to supply its inhabitants with electricity at all times, using only energy from the wind and water. Thanks to this system, the island avoids the emission of 18,000 tonnes of CO2 and the consumption of 40,000 barrels of oil every year – and it makes a saving of 6 million euros!
An inspiration for islands worldwide
El Hierro’s hydro-wind power station makes it the first island in the world to be energy independent. Many scientists and governments consider it a life-size laboratory for renewable energies. The same type of system could be employed on many of the islands also trying to tackle the issue of ensuring a reliable energy supply.
Find out more:
Main picture: Getty Images