Unlocking the Atacama Desert

 By Robin Wylie

Stretching for some 700 miles along the Pacific Coast of northern Chile, the Atacama Desert is the driest non-polar desert on Earth…

With barely any vegetation, the Atacama is in sharp contrast to the agricultural riches of Chile’s fertile south. But in recent years, the Atacama has started to produce a more modern crop: renewable energy.
Unsurprisingly for a desert, the most bountiful energy source in the Atacama is solar power. The air above the desert contains so little water vapor that the sun’s rays reach the surface virtually unimpeded, and as a result the Atacama experiences some of the most intense solar radiation on the planet.
Chile has been relatively slow to capitalize on the Atacama’s massive solar potential. But in the last few years solar power has finally begun to flourish in the desert.
In 2011, Chile had virtually no solar capacity, but a flurry of development, spurred on by huge reductions in the price of solar PV, has seen this figure soar. Today, the country has at least 1.8 GW of solar capacity, with a further 930 MW under construction and many times more in the development stages. The large majority of this development has taken place in the Atacama region. The rise of Chile’s solar program has been so rapid that Al Gore recently remarked that the country was “inspiring the world” in this regard.

Solar panels in the Atacama (Ministerio Bienes Nacionales, Flickr)

Chile’s new solar arsenal includes the 246 MW El Romero plant, located in the southern Atacama, which came online in 2016, at which time it was the largest solar plant in Latin America. The plant consists of 776,000 PV modules which track the passage of the sun, changing their angle to maximize the solar radiation they absorb.
Solar projects which are under construction in the Atacama include several solar thermal electric plants, which will be able produce energy 24 hours a day by using an array of mirrors to focusing the sun’s rays to heat a working fluid.
These include the Tamarugal solar project, a series of three, 150 MW solar thermal towers currently under construction near the city of Iquique in the far north of the Atacama, close to Chile’s border with Peru. The company that proposed this project, SolarReserve, has also proposed two others — one of 260 MW and another of 390 MW — elsewhere in the Atacama.
Its solar potential alone would make the Atacama an extraordinary renewable energy resource. But another source of heat, lying beneath the desert surface, is also starting to be harnessed.
The Atacama Desert region sits along the “Ring of Fire,” a zone of intense seismic and volcanic activity which fringes much of the Pacific Ocean. There are around 36 active volcanoes at the desert’s eastern fringes, in the Andes mountain range, which generate vast amounts of geothermal heat beneath its barren surface.
In fact, the Chilean Atacama represents one of the largest geothermal resources anywhere on Earth, with an estimated 16,000 MW of geothermal potential — enough to supply over 90 percent of Chile’s current electrical needs.
As with solar power, Chile has been relatively late to exploit the Atacama’s geothermal potential. It only opened its first geothermal plant at Cerro Pabellón, located at a height of 4,500 meters in the Andes, in September 2017.

El Tatio geyser, Atacama desert (Soulreaper, Wikimedia)

Chile’s relative lack of geothermal development sits is in contrast to other Latin American nations, such as Mexico and El Salvador, which already generate significant quantities of power from geothermal energy (in the case of El Salvador, 25 percent of its electricity needs are currently met by geothermal).
But there are reasons to be optimistic about Chile’s geothermal future. The success of the Cerro Pabellón plant (the first of its kind not just in Chile, but in the whole of South America) could encourage investors to back further projects in the Atacama. What’s more, the Chilean government are pushing a variety of initiatives that increase the competition in the energy sector and support the development of renewables, meaning that exploiting the Atacama’s untapped geothermal (as well as solar) potential, could be a natural choice in the future.
With the gigantic potential of solar energy, and the possible support of geothermal around the corner, the future of renewable energy in the Atacama looks extremely strong. The success of renewables in this region could serve as an example to follow for other nations with similar resources — notably with the upcoming deployment of solar thermal plants, a relatively under-tested technology in the solar market. But the most immediate effect of will be for the 18 million Chileans who stand to benefit from the Atacama’s newly tapped resources.
So far, the majority of the renewable energy generated in the Atacama desert has been used for nearby industry. However later this year, Chile’s northern power grid is expected to be linked to the larger central grid, which serves the large majority of the country’s residential consumers. As well as slicing Chile’s carbon output, this move should also reduce the country’s notoriously high energy costs, by reducing its reliance on imported hydrocarbons from neighboring Argentina. The Atacama desert is finally beginning to bear fruit.

READ MORE: The sea in the desert by Sara Sangermani

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.