A recent report from The International Council on Clean Transportation (ICCT), based in Washington, DC, summarized data on commercial vehicle sales and real world fuel consumption of heavy-duty tractor-trailers in three regions—China, U.S. and the European Union (EU)—which together represent more than 70% of heavy-duty vehicles sales worldwide.

The review found that average fuel consumption in the U.S. was about 39 litres/100 kilometers (l/100 km), but for the newest models, fuel consumption was lower (between 33 and 36 l/100 km).

In the EU, estimates were roughly 31 l/100 km, while tests of individual vehicles done by trucking magazines showed higher fuel consumption (36 to 38 l/100 km).

In China, chassis dynamometer testing performed as part of the regulatory development process in China showed higher fuel consumption rates, averaging 44 l/100 km.

Because the U.S. has mandatory HDV efficiency standards in place, the rate of technology development and deployment will likely be faster, the report said.

The study used national and regional fuel consumption data, aggregate data across a number of fleets, road-test data for individual vehicles and chassis dynamometer data. It was found that “[t]he data available in each category for each region varied widely, and there is a general scarcity of data on real-world fuel consumption of tractor-trailers.”

The U.S. made the most data available, followed by the E.U. China, however, had very little data available other than chassis dynamometer results. One of the main objectives of the review was to illustrate the need for more data collection and synthesis of publicly available data, as the data on HDV fuel efficiency are much less abundant than on passenger cars.

The authors also note that heavy-duty vehicles are a much larger contributor to greenhouse gas emissions than may be popularly believed. “Despite their relatively small numbers, on-road commercial vehicles are responsible for a disproportionately large percentage of transport sector fuel consumption and GHG emissions due to their heavier weight and greater number of miles traveled.”

They said that a number of other studies “suggest that in the 2020 to 2030 time frame, heavy-duty vehicles are estimated to overtake passenger cars as the largest global contributor to fuel consumption and GHG emissions within the transport sector.”