Don’t lean against the light switch at the Synlight building in Jülich, Germany—if you do, things might get rather hotter than you can cope with.

The new facility is home to what researchers at the German Aerospace Center, known as DLR, have called the “world's largest artificial Sun.” Across a single wall in the building sit a series of Xenon short-arc lamps—the kind used in large cinemas to project movies. But in a huge cinema there would be one lamp. Here, spread across a surface 45 feet high and 52 feet wide, there are 140.

When all those lamps are switched on and focused on the same 20 by 20 centimeter spot, they create light that’s 10,000 times more intense than solar radiation anywhere on Earth. At the center, temperatures reach over 3,000 °C.

The setup is being used to mimic large concentrated solar power plants, which use a field full of adjustable mirrors to focus sunlight into a small incredibly hot area, where it melts salt that is then used to create steam and generate electricity.

Researchers at DLR, though, think that a similar mirror setup could be used to power a high-energy reaction where hydrogen is extracted from water vapor. In theory, that process could supply a constant and affordable source of liquid hydrogen fuel—something that clean energy researchers continue to lust after, because it creates no carbon emissions when burned.

Trouble is, folks at DLR don’t quite yet know how to make it happen. So they built a laboratory rig to allow them to tinker with the process using artificial light instead of reflected sunlight—a setup which, as Gizmodo notes, uses the equivalent of a household's entire year of electricity during just four hours of operation, somewhat belying its green aspirations.

Of course, it’s far from the first project to aim to create hydrogen fuel cheaply: artificial photosynthesis, seawater electrolysis, biomass reactions, and many other projects have all tried—and so far failed—to make it a cost-effective exercise. So now it’s over to the Sun. Or a fake one, for now.

(Read more: DLR, Gizmodo, “World’s Largest Solar Thermal Power Plant Delivers Power for the First Time,” “A Big Leap for an Artificial Leaf,” "A New Source of Hydrogen for Fuel-Cell Vehicles")