Rising more than 200 metres above the vast, deserted plains of the Atacama desert, the second tallest building in Chile sits in such a remote location that it looks, from a distance, like the sanctuary of a reclusive prophet, a temple to ancient gods or the giant folly of a wealthy eccentric. Instead, this extraordinary structure is a solar power tower that is being built to harvest the energy of the sun via a growing field of giant mirrors that radiate out for more than a kilometre across the ground below with a geometric precision that is reminiscent of contemporary art or the stone circles of the druids.
Still under construction, the Atacama 1 Concentrated Solar Power plant is a symbol of the shift from dirty fossil fuels to a cleaner, smarter way to generate electricity in Chile which is leading the charge for solar in Latin America thanks to its expanses of wilderness and some of the most intense sunlight on Earth.
Following the global climate change deal signed in Paris earlier this month, the $1.1bn project is a source of hope because it demonstrates how far renewable technology has come. But – amid reports of its Spanish owner Abengoa’s financial difficulties – it is also a reminder of how the energy transition is increasingly challenged more by financing uncertainties than engineering obstacles.
The main structure – which is already taller than London’s Gherkin or New York’s Trump Tower – is almost finished. The next big challenge will be to lift one of the heaviest slabs of steel ever made – the 2,000-tonne solar receiver – to the top with hydraulic jacks. This will be used to heat a pool of 50,000 tonnes of molten salt up to temperatures of 565C during the day so it can continue to drive turbines through the night. All that is needed after that is to polish the 10,600 heliostatic mirrors so that they can reflect sunlight up to the tower. The end result will be the dream of sustainable energy supporters – a solar facility that can provide baseload power generation of 110 megawatts (MW) for 24 hours a day.
Read more on solar power from The Guardian