BMW’s Hydrogen 7, which has garnered attention for being test-driven by a roster of celebrities, has been put through rigorous testing by the U.S. Department of Energy’s Argonne National Laboratory. Scientists at the facility have confirmed that the vehicle produces virtually zero emissions. The tests have shown that the Hydrogen 7’s engine operates at a level that exceeds the Super Ultra Low-Emission (SULEV) vehicle standard.

“The BMW Hydrogen 7’s emissions were only a fraction of SULEV level, making it one of the lowest emitting combustion engine vehicles that have been manufactured,” Thomas Wallner, the Argonne lab’s lead hydrogen vehicle testing engineer, told Science Daily Magazine. “Moreover, the car’s engine actively cleans the air. Argonne’s testing shows that the Hydrogen 7’s 12-cylinder engine actually shows emissions levels that, for certain components, are cleaner than the ambient air that comes into the car’s engine.”

Instead of using hydrogen to generate electricity in a fuel cell, the BMW Hydrogen 7— essentially a 7 Series sedan—burns hydrogen in its conventional V-12 engine. The version of the Hydrogen 7 tested by the Argonne Lab is a mono-fuel vehicle, only capable of running on hydrogen. Previous versions can switch to straight gasoline at the driver’s whim. Think of it as a dual-fuel gasoline-hydrogen hybrid. A full tank of liquid hydrogen will grant a vehicle range of more than 125 miles. Add a full tank of gasoline for another 300 miles of interstate driving. Put those two together and the BMW Hydrogen 7 can drive about 450 miles on a full supply of fuel.

There’s little hope that the BMW Hydrogen 7 will be put into production. Instead, the idea is for BMW to get more experience using hydrogen fuel in real world. The BMW Hydrogen 7 runs on liquid hydrogen, not gaseous hydrogen. There are only about 50 hydrogen fueling stations in the United States, and just a handful of those dispense liquid hydrogen. The temperature of hydrogen must be maintained at about 400 degrees below zero Fahrenheit to remain in a liquid state.

The findings of these independent tests will be presented on April 2 at the National Hydrogen Association Annual Hydrogen Conference in Sacramento, California.