Field Operations Program staff at NREL are evaluating SunLine Transit Agency's experience as it adds state-of-the-art hydrogen fuel cell buses to its fleet and sets up infrastructure facilities for fueling and maintenance. Because fuel cell buses aren't yet commercially available, this prototype fuel cell bus demonstration project will help increase understanding of the technology and plan for future evaluations.

In 1994, SunLine converted its entire bus fleet to run on CNG. Today, the fleet boasts 46 CNG, one hydrogen fuel cell, two hythane (80% CNG, 20% hydrogen), and three battery-electric buses, with more advanced vehicles on the way. In 2000, SunLine opened the first hydrogen generation, fueling, storage, and education facility ever built by a public transit agency. Hydrogen is produced at the site using solar-powered electrolysis and natural gas reforming.