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CARB Releases Proposed Regulations for Innovative Clean Transit

The California Air Resources Board (CARB) is developing strategies to transition the heavy-duty trucks and other mobile sources of emissions to zero and near-zero emission technologies to meet air quality, climate, and public health protection goals. The long-term vision of the Innovative Clean Transit (ICT) effort is to achieve a zero-emission transit system by 2040 as a key step in that transition.

Transit agencies have been leaders in addressing air quality through their role in providing sustainable transportation options for the public, especially for their service to low-income and disadvantaged community residents. Transit agencies have also been at the forefront in the adoption of new technology such as natural gas engines, and those powered by renewable natural gas, to reduce emissions and in addressing barriers to their implementation.

The proposal is intended to provide flexibility and to encourage transit agencies to implement plans that are best suited for their own situation. Key elements of the proposal relevant to the natural gas vehicle industry include the purchase of renewable fuels when natural gas contracts are renewed, and the purchase of low NOx engines if available for bus purchases.

Starting January 1, 2020, small and large transit agencies must purchase low NOx engines when new conventional bus purchases are made:

  • The requirement applies to engines that have been commercially available for at least two years.
  • The engine must be certified to the lowest level of NOx emissions that is suitable for the bus and fuel type being
  • The requirement does not apply to buses that are dispatched from areas defined as NOx exempt
  • Any early low NOx engine purchases will count towards compliance with the low NOx engine

Starting January 1, 2020, large transit agencies will be required to use renewable fuels for CNG buses when fuel contracts are renewed to support existing programs. Transit agencies’ use of renewable natural gas (RNG) will not produce additional emission reduction outside of the Low Carbon Fuel Standard (LCFS) program. However, such requirement will help stimulate the LCFS market.

In addition, each year starting in March 31, 2021, all transit agencies will be required to report their fleet information for the prior compliance year and will need to meet record keeping requirements. For the initial report, transit agencies will need to report information on all active buses in the fleet as of December 31, 2017 that are in the scope of the regulation with a GVWR greater than 14,000 lbs. to determine fleet size. All transit agencies are required to report bus type, engine, powertrain information, number of bus purchases, leases, conversion, and dates that buses are added or retired from the active fleet. Large transit agencies will also need to report purchases of renewable fuels.

A copy of the full draft proposal is available for review here.