We visit El Hierro. The smallest of the Canary Islands with only 10.000 inhabitants. It is the most southern part of Spain. And it can be 100% self-sufficient with renewable energy.
The island is so far away from the mainland, that no electricity cable was ever laid. The old diesel-fired power station is built near the main port.
The most logical source of renewable energy on El Hierro is wind power. Even in the protected harbor the wind is blowing. For the island, a Nature 2000-reserve, it was also important to choose a source that does not interfere with the landscape. And although the trade wind is pretty reliable, the energy supply needs to be constant, not depending on when the wind blows, .
So, besides the five wind turbines with a total capacity of 11.5 MW, they built two water reservoirs. One at sea level and a second one at an altitude of 700 meters. All left over energy, generated by the wind mills, is used to pump water to the upper reservoir. When there is no wind, the water will flow from the upper reservoir to the lower one through the hydroelectric power station, where turbines generate the electricity needed on the island also when there is no wind.
Tucked away
When we approached the island, we hardly saw the windmills.
The 5 windmills are set in a valley. They are catch all the wind accelerating along the mountain ridge, and can be low enough not to dominate the landscape. Also, the water reservoir has a cleverly and respectfully located. It lies in a natural basin. The pipelines lie out of sight in a valley. So, all installations fit in the natural environment.
The company is proud of this achievement and welcomes visitors. Even though the combination of wind- and hydropower seems very innovative, it’s all existing technology, like on Ya. The pumps are standard and you see the turbines in many other hydroelectric power stations around the world.
Since the plant operates from 2015, and delivers an increasing part of the island’s energy by this combination of wind and hydropower. Only if there is too little wind and the water level in the upper reservoir is too low, the company will fall back on the old diesel generators. The company is constantly improving the management of the installations. Interesting: the island’s energy mix is publicly accessible. It helps well in cutting down the usage.
Awareness
What we really like about this initiative, is that Gorona del Viento not only invests in generating energy. It also invests in awareness. On their website and in their talks on schools., they stress the importance of saving energy. Not only by distributing LED-light bulbs, but also by mentioning the bigger issue: water. Almost half of the fresh water on the island is produced in desalination plants. The production and distribution of water accounts for approximately 45% of annual electricity consumption. So logically, they also stress the importance of saving on water consumption.
For their efforts, in June 2021, Gorona del Viento El Hierro, has won the second place in the RESponsible Island Prize. The jury liked the energy generation, the commitment to clean transport, and the awareness-raising campaigns. It has demonstrated that a reliable power supply can be generated from renewable energy, even if it comes from intermittent sources, in order to give stability to the network. “This is a pioneering project that is now inspiring other territories”.
For this article, we thankfully used Sailors for Sustainability’s article on El Hierro. They also made this great video on their visit to the island.