Two slim towers rise from the fields 20 miles west of Seville, each bathed in the rays of an otherworldly glow. Though they look like portals to another dimension, they serve a much more practical purpose: They are the "power towers" of Solucar, the largest solar energy complex in Europe.
The towers, named PS10 and PS20, began operating in 2007 and 2009. Each is surrounded by a field of angled mirrors known as heliostats, which reflect solar radiation onto a receiver located at the top of each tower. This reflected sunlight illuminates dust and water vapor in the air, resulting in the brilliant glowing rays.