The theme for this year’s Los Angeles Auto Show Design Challenge was a Highway Patrol Vehicle for 2025, and Mercedes-Benz‘s entry was a reworking of the automaker’s iconic G-Class. The resulting concept, dubbed the Ener-G-Force, is an off-road vehicle for the California Highway Patrol that’s eco-friendly. It uses an onboard “hydro-tech converter” to use hydrogen from recycled water (which can be collected from the roof rack) to power fuel cells, with batteries housed in the Ener-G-Force’s side skirts. Four independent wheel hub motors drive the vehicle, with a driving range rated at 500 miles. Finally, a roof-mounted “Terra Scan” device scopes the topography ahead and adjusts the suspension and ground clearance accordingly. The Ener-G-Force is one of six entries for the 2012 LA Design Challenge, with the winning design set to be announced November 29th.