Tenerife may have just found something rather interesting beneath its feet.
Deep drilling near Vilaflor has uncovered evidence of heat, water above 150°C and permeable rock at around 2,300 metres below the surface. Those three things together are important because they are the basic ingredients needed for a viable geothermal energy system.
And if further testing confirms what the initial results are suggesting, Tenerife could have access to a renewable source of electricity that works day and night, regardless of whether the sun is shining or the wind is blowing.
A promising discovery beneath Vilaflor
The drilling is part of a long-running investigation into Tenerife’s geothermal potential, carried out by British company Marriott Drilling Group through the public-private consortium Geothermal Energy of the Canary Islands (EGC).
The consortium includes the Cabildo de Tenerife and other energy companies.
The project has now gone beyond 2,500 metres, with further drilling planned in the same area and at another location around four kilometres to the east. The aim is to reach depths of around 3,000 metres over the coming months.
Until now, much of the research into geothermal energy on Tenerife has relied on studies of what is happening at the surface.
This is different.
For the first time, deep drilling has provided direct evidence of the conditions scientists have been looking for underground.
Could Tenerife generate electricity from it?
The initial tests point towards a natural geothermal recharge system, where underground water is heated by the high thermal flow beneath the island.
If the next stages confirm that the heat, water flow and permeability are suitable, that underground heat could potentially be used to generate electricity.
The initial assessment puts the likelihood of a suitable system at more than 60%.
That’s encouraging, although there is still a fair bit of work to do before anyone starts plugging Tenerife into a geothermal power station.
The important thing is that the basic ingredients appear to be there.
Why geothermal could be useful in Tenerife
Tenerife currently gets around 80% of its electricity from fossil fuels, with the remaining 20% coming from cleaner energy sources.
Solar and wind have obvious advantages, but they are dependent on the weather and time of day.
Geothermal is different. Once developed, it can provide a stable and continuous source of electricity, which could sit alongside existing renewable generation rather than replacing it.
That could make it particularly valuable for an island that still depends heavily on imported fossil fuels.
A geothermal plant producing 10 megawatts could potentially save Tenerife around €19 million a year in fossil fuel imports and avoid approximately 65,000 tonnes of CO₂ emissions annually.
That amount of generation could provide enough electricity for around 24,000 homes.
Tenerife isn’t the only island looking underground
The work in Tenerife forms part of a wider interest in geothermal energy across the Canary Islands.
Gran Canaria is developing its own pilot well, while La Palma is progressing more slowly due to administrative delays.
Tenerife now has something the other islands don’t have in quite the same way: direct evidence from deep drilling that suggests the conditions for geothermal energy may actually exist beneath the island.
There is still a long road between finding hot water underground and producing electricity commercially.
But after years of studies, drilling to more than two kilometres down and finding temperatures above 150°C is a pretty significant step.
For Tenerife, which is still importing huge amounts of fossil fuel to keep the lights on, it’s certainly something worth paying attention to.