The Earth’s natural power plant — the sun — bathes the planet with more than enough green energy to fulfill all our power needs. However, while we have managed to harness some of it through solar panels, most of its potential remains untapped. Finding new ways to capture more of this unlimited sustainable energy has proven tricky given that the sun doesn’t work at night, often hides behind clouds, and in some areas of the world, disappears altogether for months at a time. Now, scientists and engineers at the German Space Center (DLR) in Jülich have built a more reliable and controllable substitute to enable researchers to discover new ways to capture the sun’s energy.