On a barren, sun-baked plateau in southern Spain, row upon row of gleaming mirrors form one of the world's biggest solar power plants and harness the sun's power even after dark.
Near the town of Guadix, where summer temperatures often top 40 degrees Celsius, the main sound at the site is a whirring of motors to keep the mirrors - mounted on giant steel frames - tracking the sun as the Earth turns.
Solar power has massive potential - one U.N. study estimated the world's electricity needs could be generated by harvesting solar power from an area of the Sahara 800 km by 800 km.
And in 2014, a report by the International Energy Agency said the sun could - with a radical shift in investments - be the world's largest source of electricity by 2050, ahead of fossil fuels, wind, hydro and nuclear.
Capacity just from solar thermal plants like Andasol could expand to 1,000 gigawatts a year from 4 gigawatts at the end of 2013, the agency said.
But solar power has been risky for many companies and investors. Low-price Chinese exports have hit rivals in other parts of the world, especially those dependent on subsidies by governments, many of which have been cutting support. Still, a sharp fall in prices of photovoltaic panels and improved technology that captures more power from the sun has placed solar energy on the cusp of a global boom, analysts say.
The ‘Earthprints’ series are multimedia stories showing dramatic human impact on the planet in the last 30 years. Released ahead of the UN Climate Conference COP21: Cancun, Rio Pardo, Lake Nakuru, Aletsch Glacier, Leslie Street Spit, Lake Powell