In February 2000, ARB established a new transit fleet rule for transit agencies which included the zero emission bus (ZBus) regulation. Each transit agency was required to select a compliance path—either the “diesel” path or the “alternative fuel” path—by 1 January 2001. Path selection set the fuel type for new urban bus acquisitions through model year 2015. Transit agencies on either path were required to achieve fleet reduction requirements for NO_x and PM emissions.

The zero emission bus portion of the rule promoted advanced technologies—battery-electric, electric trolley, or fuel cell—by adopting ZBus demonstrations, applicable to diesel path agencies, and ZBus acquisition requirements applicable to transit agencies on both fuel paths. There was a 15% ZBus purchase requirement affecting only large agencies (>200 buses).

In June 2004, ARB staff proposed amendments to the demonstration project requirements. After reviewing the status of technology and meeting with bus manufacturers and transit agencies, ARB staff concluded that an adequate number of ZBuses, particularly fuel cell buses, were not available. The Board amended the demonstration project requirements by reducing the number of buses required to three per demonstration project, instead of three per transit agency. The Board also extended the date that demonstration buses were to be in operation to the end of February 2006.

The regulation was amended in 2006, the Board pushed off the purchase requirement to 2010, but gave the executive officer (EO) the ability to suspend the requirement so long as cost, durability and performance remained issues. The EO has suspended the purchase requirement indefinitely since 2010.

The Board will now be be considering changes or amendments to regulation which may affect the 15% purchase requirement.

At the workshop, ARB will establish the continued need for ZBus technology development. ZBus manufacturers and technology providers will discuss the current state of zero-emission bus technology and where they anticipate this technology will be in the near, and medium-term future. In addition, transit agencies will share their experiences with procuring zero emission buses, operating within urban fleets, and maintenance challenges and opportunities.

Staff plans to hold additional workshops following this workshop to explore regulatory options and to take comments on draft amendments prior to taking the regulatory package to the Board in May 2014.