Photo by Ivan Radic via Flickr

Global greenhouse gas emissions from passenger cars, trucks and buses made up almost three-quarters of total transport emissions in 2020, underscoring the importance of a rapid transition away from fossil-fuel-powered vehicles.

Passenger cars are on the way to decarbonization, but they need a push to keep us on track for a 1.5 degrees C world.

The world is on the cusp of a transformation in motor vehicles, with sales of electric vehicles (EVs) skyrocketing in 2022 in the key markets of China, Europe, and parts of the United States. If this trend continues, it will have broad ramifications for the global automobile industry and global transport sector emissions.

According to Bloomberg NEF, passenger EVs are projected to displace close to a million barrels of oil per day by 2025, with global gasoline demand projected to peak the following year. Under this scenario, the EV share of total passenger vehicle sales is projected to reach 23% by 2025, up from 10% in 2022. But more action is needed if sales are to reach 75-95% by 2030 — the range compatible with 1.5 degrees C (2.7 degrees F) climate goals.

Timeline showing Key milestones in the exponential growth of electric vehicle sales compared to the EV share of global new passenger vehicle sales

Progress on zero-emission trucks and buses needs a jolt, especially outside of China and Europe.

Progress on decarbonizing truck transport is not as advanced as it is with passenger cars, but there are promising signs. Several electric heavy-duty truck models are already commercially available or in an advanced stage of development, and electric medium-duty vehicles are starting to be rolled out in many corporate fleets.

Long-haul, heavy-duty trucks will be the most challenging class to decarbonize. Battery energy density for these models is currently a limiting factor, and recharge times affect corporate profitability. However, the newest trucks can travel 300 kilometers (km) on a single charge, and additional battery technology improvements are estimated to enable a 40 tonne truck to drive 400 km on a single charge by 2025, suggesting that there could be rapid technological change in even the heaviest vehicles.

Though hydrogen fuel cell models do not share the energy density challenges faced by battery electric models, they are still in the early stages of development and renewable hydrogen continues to be prohibitively expensive. In addition, hydrogen as a transport fuel must contend with the significant efficiency losses incurred through the production and transportation process — losses that are not a factor for battery electric models. Progress will require investments in hydrogen supply chains in addition to refueling infrastructure.

Progress on decarbonizing buses remains extremely uneven, with very high sales in China pushing the global sales share of zero-carbon models up significantly. The United States has seen a large increase in the past year thanks to a major deal for manufacturer SEA Electric to convert 10,000 of Midwest Transit Equipment’s buses to electric over the next five years. In the rest of the world, zero-carbon buses have yet to make large inroads. 

Tracking progress on global outcomes

Key enablers and barriers to change

Other shift Other shifts needed to transform the system

Guarantee reliable access to safe and modern mobility

All people deserve access to safe transport and mobility options. The transition of the world’s energy systems to decarbonized travel modes must be accomplished equitably in a way that provides opportunity for everyone.

Reduce avoidable vehicle and air travel

The most cost-effective means of reducing transport emissions is to avoid the need for motorized travel, utilizing city planning to bring opportunities closer to residents and encouraging less carbon-intensive modes of movement, such as public transport, walking and cycling.

Shift to public, shared and non-motorized transport

Achieving a sustainable, low-carbon transport system demands a comprehensive approach: avoiding unnecessary trips, shifting travel to more sustainable modes, improving transport technology and increasing access to jobs and opportunities.

Transition to zero-carbon shipping and aviation

Although both shipping and aviation are seen as “hard-to-decarbonize,” both sectors have pathways to a greener future. Decarbonizing shipping and aviation will require a combination of technological solutions, such as zero-emission fuels and batteries, alongside operational and efficiency improvements.