100% renewable targets will require power storage to manage flows on the net
Electrolysers utilise these intermittent power flows to produce H2 gas from water
H2 gas can be stored in large quantities underground and transported via existing gas pipelines
H2 vehicles recharge faster and are more durable than battery powered transport
Growing H2 demand in industrial processes will reduce costs and increase supply

The Zero Emission Bus (ZBus) regulation is designed to encourage the operation and use of zero emission buses in California urban bus fleets. The ZBus Regulation is part of the Fleet Rule for Transit Agencies, which is also referred to as the Public Transit Agencies Regulation.

The Air Resources Board held a workshop on December 3, 2013 at the Metropolitan Transportation Commission. The workshop summarized the four panels (fuel cell electric bus, battery electric bus, ZBus infrastructure, and transit fleets operating ZBuses) from the first workshop on September 17, 2013, and the common themes expressed during the individual stakeholder meetings staff have been conducting. This work shop focussed on the potential regulatory concepts and options under consideration for ZBus deployment and will include a discussion of a planned broader look at the transit fleet rule that will occur in 2014.

More information here.