All new city buses to be electric by 2029 in California

New regulation expected to cut greenhouse gas emissions by about 17 million metric tonnes between 2020 and 2050

All new mass transit buses in California will have to be fully electric by 2029, according to a new rule adopted by the California Air Resources Board (CARB).

The new rule also mandates all municipal bus fleets in the state must become fully electric by 2040.

According to CARB, the new regulation should cut greenhouse gas emissions by about 17 million metric tonnes between 2020 and 2050. It will also help reduce emissions of nitrogen oxides (NOx) and particulate matter by about 6,250 tonnes and 36 tonnes, respectively, over the same period, CARB claims.

California's public transport sector is responsible for nearly 40 per cent of the greenhouse gas emissions and 80-90 per cent of smog-forming pollutants

"[A zero-emission public bus fleet] dramatically reduces tailpipe pollution from buses in low-income communities and provides multiple benefits especially for transit-dependent riders," CARB chairwoman Mary Nichols said in an official statement.

The Innovative Clean Transit regulation approved by CARB is the first of its kind in the US. California's public transport sector is responsible for nearly 40 per cent of the greenhouse gas emissions and 80-90 per cent of smog-forming pollutants in the state.

At the moment, California has just 153 electric buses running on its roads, out of approximately 12,000 in the state.

Over the next two years, about 1,000 more electric buses are expected to be brought into service by 200 mass transit agencies operating in California.

Starting in 2029, all agencies will only be allowed to purchase zero-emission buses for their fleet. However, starting in 2023, at least 25 per cent of their new buses must be electric and the requirement will rise to 50 per cent by 2026.

While, transition to fully electric buses will be a costly affair for the state and the public transit agencies, the local communities would be able to save about $1.5 billion in fuel, maintenance, and other costs by 2050, as per CARB estimates.

Some environmentalists also hope that state's new regulation would also spur electrification of other types of vehicles, including trucks, forklifts, and UPS trucks, in California.