At General Motors, development on fuel cell vehicles stretches back more than half a century. The 1966 Electrovan, a converted GMC Handi-Bus with hydrogen-oxygen power, could reportedly do 70 mph and travel 150 miles.

Their immediate potential may wax and wane, but hopes remain high for fuel cell vehicles. They offer the cleanest power available—if and when the obstacles can be overcome. The Electrovan, a General Motors project from 1966, is generally credited as the industry’s first working fuel cell vehicle.

A spinoff of GM’s fuel cell work with NASA, the Electrovan was based on a production GMC Handi-Bus platform, but with all the necessary equipment on board, the compact van weighed a hefty 7,100 lbs. The gear included two cryogenic tanks, one for oxygen and one for hydrogen, while 32 thin-electrode fuel cell modules connected in series lined the floorpan. A 45-gallon reservoir and 550 feet of plastic tubing handled the potassium hydroxide electrolyte, which itself accounted for 550 lbs. The layout and components shown in the GM cutaway below.

There’s an energetic controversy these days between the advocates of fuel-cell and battery-electric vehicles. But as EV consultant and engineer Ryan Maughan of AVID Technology points out, it’s sort of a lopsided debate, insofar as the auto industry is concerned. In truth, both fuel-cell and battery vehicles are electric, with many of the same component systems and challenges. The difference is simply in the source of the energy.

Despite the considerable weight and other limitations of the technology, the Electovan could do 0-to-60 mph in 30 seconds, reach a top speed of 70 mph, and travel 150 miles, according to GM. When the project was concluded, the little bus disappeared for several decades before it was rediscovered in a GM warehouse in Pontiac, Michigan in 2001. GM’s fuel cell development work is still carried out in Pontiac, while the Electrovan, polished and looking like new, lives in the GM Heritage Collection of historic vehicles in nearby Sterling Heights. The short clip below shows the Electrovan tooling around the streets of the GM Technical Center circa 1966, which is fun to see in itself. While we’re at it, check out the tasteful customizing performed on the Handi-Bus by GM Styling VP Bill Mitchell and crew. Video below.