Transportation efficiency in 2030

Transportation of people and goods currently contributes about a quarter of the world’s greenhouse gas emissions, and this share is growing. Unprecedented income and population growth in the developing world is driving demand for both passenger cars and freight shipment of consumer goods. In China alone, for instance, automobile ownership was twenty times higher in 2010 than in 2000, and is expected to double again by 2030 to nearly 600 million vehicles[1] –  350 million more than the US’s current vehicle fleet.[2]  In India, the number of cars on the road tripled between 1990 and 2006 and will continue to grow.[3]  It is no wonder that global emissions from transportation have grown 30% since 2000.

In the course of our work on vehicle regulation the ICCT does some modeling of different transportation scenarios, both globally and on a national or regional scale. The chart here shows our estimate of the likely trajectory of GHG emissions from transport through 2030 under what we call the “policy pipeline” scenario in the seven largest vehicle markets. This scenario is based on policies that have either already been enacted or are under active discussion by regulatory agencies. Neither a business-as-usual projection nor a pure assessment of technology potential, it is intended to reflect the political and regulatory context.

ICCT chart

The size of each bubble represents that country’s total greenhouse gas emissions in 2000 (solid bubble) and its projected emissions in 2030 (translucent bubble) assuming the adoption of policies in the pipeline. The x and y axes represent the efficiency of passenger and freight transportation systems, respectively. In other words, it represents the amount of CO2 that is emitted to move one passenger or one ton of goods by one kilometer. As vehicle fleets become more fuel efficient (more distance traveled or freight shipped per unit of fuel), and more activity is shifted to energy-efficient modes, the bubbles move closer to the origin.

With the recent adoption of new fuel economy standards for new passenger vehicles manufactured between 2017 and 2025, the US will see the most dramatic efficiency improvements, catching up to the EU’s present-day CO2 per passenger kilometer levels and reducing its total emissions more than 8 percent. The other OECD countries will also see modest drops in total emissions.

However, in developing countries, market growth outweighs the effect of stronger policies.  China, for example – now the world’s largest vehicle market – has pledged to reduce economy-wide carbon intensity 40 to 45% by 2020 and has adopted policies towards this goal, including fuel economy standards for new passenger and light commercial vehicles. India and Mexico plan first-ever mandatory fuel economy standards by 2012/2013. Nonetheless, the enormous boom in car ownership means the bubbles still get bigger by 2030. Overall, the growth in emissions from emerging markets outweighs the drop from the OECD countries.

How do the trends above compare to projections in other sectors? A March 2012 report from the OECD projects that emissions from deforestation and other land use changes will decrease by 2050, total energy emissions will increase by 50%, but transport emissions will double. This is consistent with a World Bank estimate that transportation will become the single largest source of global greenhouse emissions by 2035, and by 2050 will reach 80% of the total.

The potential impact on climate would be far worse without the important improvements already made in vehicle efficiency standards and technology. 70% of the world’s transportation emissions have come under regulation over the past three decades. And technology already exists that could make vehicles 35–50% more efficient by 2020. 

The scientific consensus is that preventing major destabilization of Earth’s climate will require much more drastic emissions reductions than we are currently on track to make. Cutting emissions from transportation will become even more important in the near future, not only because of the growth discussed above but because the sector is relatively more flexible. The International Energy Agency considers 80% of power plant emissions in 2020 to be already “locked in.”   Both because of its relatively greater flexibility and responsiveness to policy and because of the growth modeled above, the transportation sector must become a major focus of climate change efforts.



[2] USDOE Transportation Energy Data Book, Table 3:

[3] Urban Transport Trends and Policies in China and India: Impacts of Rapid Economic Growth