While hydrogen is the most common element in the universe, it is rarely found in its pure state on earth. Instead, it is bound up in compounds such as water or methane (natural gas). It takes energy and a production facility to produce hydrogen from these compounds.

Rather than trucking or piping pure hydrogen over long distances, the National Academy of Engineering recommends building small-scale hydrogen production facilities at the sites where hydrogen will be used.

Two of the most promising options for small-scale, onsite production are electrolysis---breaking water into hydrogen and oxygen-and steam methane reformation. At AC Transit, we're doing both.

At our Oakland Seminary Division, Chevron Corporation has built an energy station that produces hydrogen from natural gas. The station entered service at the beginning of 2006. It can dispense up to 150 kilograms of hydrogen daily-enough to fuel our three fuel cell buses, along with a fleet of light-duty fuel cell cars. The facility has the potential to expand to match the demand of a growing fleet.

From 2002 through 2007, AC Transit operated an electrolysis station built and maintained by Stuart Energy and Hydrogenics in partnership with the California Fuel Cell Partnership (CaFCP). This station produced up to 24 kilograms of hydrogen daily from the electrolysis of water. The station could fuel as many as five cars within eight minutes and was the primary fueling station for AC Transit's prototype 30' bus and light-duty vehicles in the CaFCP. The station was critical to the launch of AC Transit's hydrogen program.

This station's usefulness was eclipsed by the opening of the steam-methane reformer at AC Transit's Oakland Division. While electrolysis remains a promising technology, it is not currently the most cost-effective means of producing hydrogen.

In partnership with Avalence, LLC of Connecticut, and the US Department of Energy, AC Transit is exploring the possibility of installing a solar-powered, high-pressure electrolyzer. This station would use the sun's energy to produce hydrogen from water, and could go into service within the next year, producing from 5 to 10 kg of hydrogen per day.