The First Energy Self-Sufficient Island
Wind farm and hydroelectricity independently support population of 10,000 in Canary Islands
A tiny burst of green off the West African coast, El Hierro has long been considered a backward outpost of Spanish rule. But the smallest of the Canary Islands is about to make history—and a windfall—on its own terms.
When five wind turbines at the volcanic island’s northeastern tip begin operation at the end of June, El Hierro will become the world’s first energy self-sufficient island.
El Hierro’s $110 million 11.5-megawatt turbine farm will generate energy from gusts that buffet the coast to support water desalination plants and 10,000 residents. Wind power is expected to cut yearly carbon dioxide emissions by 18,700 metric tons and deliver a deathblow to annual consumption of 40,000 barrels of oil. In the event of heavy winds, El Hierro expects to sell surplus energy and profit handsomely, boosting the island’s budget by one to three million euros (between $1,400,000 and $4,200,000).
El Hierro is not the first island to enjoy clean-energy independence through wind. The Danish island of Samso, guilty of high carbon emissions due to oil consumption and electricity imported by cable from the mainland, began conversion to all renewables in 1998.
But El Hierro is the first island to transition in energy isolation. El Hierro never had the luxury of cabled electricity. The topography of the seafloor surrounding the island can’t sustain an interconnected electric grid.
“The true novelty of El Hierro is that technicians have managed, without being connected to any national network, to guarantee a stable production of electricity that comes 100 percent from renewable energy, overcoming the intermittent nature of the wind,” climate historian Alain Gioda said in an interview with Agence France-Presse.
That isolation means El Hierro had to create a Plan B in the event of insufficient wind or surplus energy needs. To that end, engineers built a large reservoir in synchrony with the wind farm; should the turbines fail, energy reserves will get a second wind as water is released from the reservoir with the dregs of wind-generated power. As with hydroelectric dams, gravity-induced water pressure creates kinetic energy that powers turbines as the water flows past.
The wind farm is co-owned by El Hierro and Spain, which has had success incorporating wind power into its own energy mix.
Wind and water power are just the beginning. The island has partnered with the Renault-Nissan alliance with the goal of running its 6,000 vehicles entirely on electricity by 2020.