Report about El Hierro
El Hierro is the most Western of the seven Canary islands – with a population of just over 10,500 – and declared a Unesco biosphere reserve in the year 2000. From the airplane, we see a mostly barren land – partially moonlike, partially overgrown with shrubs and a few scattered palm trees at the coast. The volcanic history of the island is evident: the island rises from sea level to up to 1,500 meters of elevation in just a few kilometers.
As we exit the airplane, we are welcomed by an unexpected heat – the usually temperate climate has been “hit” by Calima, as locals call the African desert winds that have the thermometer soaring to over 30°C. We’ve come here to visit a groundbreaking project in progress, one of the most fascinating and systemic we have encountered to date. For in 2002, the “Cabildo” (local government) approved an ambitious project: turning the island self-sustainable with renewable energy.
Five years later, the technical feasibility was concluded and the public funds appropriated. A public private partnership (PPP) was formed between the Island Council (60%), Spanish energy monopolist Endesa (30%) and the Canary Islands Technological Institute (10%). This project developer called “Gorona del Viento El Hierro” received 65 million EUR as project budget, the majority in the years 2010-2012 during construction.
The idea is stunningly systemic: five Enercon wind turbines of 2.3 MWp each will generate up to 11.5 MW of electrical power for the islands consumption. With current peak demand at 7 MW, up to one third of the energy can be stored when the turbines are operated at full power. This takes place in the form of water pumped into a deposit of half a million m³. From there, the water is released into two aerial pipelines when wind power is too low – over a length of 3km (530m underground), a difference of nearly 700 meters in altitude leads to up to 11.3 MWp of hydro power to substitute times of less wind.
The ingenuity of the project lies in the details: the majority of the electrical energy used on El Hierro is required to run the three desalination plants to generate drinking water. 70 to 80% of this water is used for agriculture. So what at first seems like a simple energy project is in fact a project to provide self-sufficiency to an island that always suffered from the scarcity of water and thus food. In the medium term, El Hierro has planned to install a second storage system for its excess energy: electric cars with exchangeable batteries will replace 40% of the vehicles on the island by 2020.
The energy alone will save 1.8 million USD p.a. currently spent on 6,000 tonnes of diesel which will be substituted, as well as saving emissions of 18,700 tonnes of CO2. However, when e-mobility comes into play, significant additional savings become possible – and all that money will circulate in and strengthen the local economy, no longer leaving the island. The local government also has the vision to be able to provide the water generated from the islands own energy cheaper to the farmers – in return for farmers agreeing to switch to organic agriculture. And several other sources of renewable energy could be tapped in future, such as solar-thermal and photovoltaic – the Canary islands know only an average of 35 days of rain every year, the rest is mostly pure sunshine!
During our visit, we are able to look at the progress made so far. The five wind turbines greet any visitor leaving the airport at the third bend in the road: their white masts reach high from a hilltop. At the time of project planning, they were among the largest turbines available – today, larger ones exist, though I’m not sure longer blades could have been transported around the tight bends of the road as it curves up the steep mountain side.
Our next stop is the upper deposit. Situated in the natural volcanic crater “La Caldera” it has been completed: a thick layer of PVC sheet secures waterproofing. Since a natural crater was chosen instead of digging deeper, static testing had to be undertaken to establish the sturdiness of the site. As it turned out, a concrete foundation – though more durable – would have been too heavy, so the plastic alternative was chosen and construed in a way so as to allow for underwater repairs.
Further down the road, we can see large parts of the two pipelines leading downhill. The first section is underground so as to protect the ecosystem above and we can see that the link between the tunnel and the continuation above ground is pretty much all that is required for finalization.
Driving back down to sea level, we arrive at the lower deposit. Here, the waterproof sheeting is just being put in place. The building around the hydraulic generators has been completed and the gigantic inverters are gleaming in the sunlight, waiting to be installed. Trucks are driving up and down the construction site, appearing miniature in comparison to the hole that was dug here to create the deposit. Representatives of Gorona del Viento are positive they will complete all necessary construction by the end of the year to begin testing and have the site live in 2013. Similarly, the aim is to complete the feasibility study for e-mobility by the end of this year.
The progress made to date is impressive, considering the circumstances – construction is one year behind but definitely nearing completion. Yet we also know that between the vision and project reality, there is still some way to go. Gorona del Viento considers itself an energy supplier – the fusion of energy and water utilities was not achieved. Farmers are often cultivating tropical crops like bananas which require high amounts of water – a focus on plants better adapted to arid regions would seem helpful. We also found canary pines populating the tops of the mountains, where clouds accumulate in the morning and leave enough moisture in the air to support their growth. Forests like this generate shade, leading to more moisture, leading to more vegetation – possibly an opportunity to learn from the (reforestation) projects undertaken in Las Gaviotas in Colombia?
El Hierro may be a small island, but one that could be a reference to the world. 17 million Europeans and 600 million people worldwide live on islands, many of them remote. We wish the people driving this project the best of luck in their efforts to realize this example of systemic solutions to create a prosperous future for their community.
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