Canadian researchers uncover what they think is the real driver of transport demand

Commuters are seen in a Seoul, South Korea subway station in this April 6, 2012 file photo. (AP Photo/Lee Jin-man)

A new global study suggests that people everywhere, regardless of country or wealth, spend almost the same amount of time travelling each day — about 78 minutes.

This consistent “travel-time budget” may be the key to predicting and reducing future transport-energy demands, according to the study.

Published in the Environmental Research Letters, the research — led by the Institute of Environmental Science and Technology at the Universitat Autònoma de Barcelona, in collaboration with Canada’s McGill University — observed mobility data from 43 countries representing, more than half of the world’s population.

Despite vast differences in transportation systems, urban design and income, the study found that daily travel time varies only within a narrow 12-minute range.

Researchers say this fixed-time budget overturns longstanding assumptions about how societies use energy for movement. Traditional models often focus on reducing kilometres travelled or improving fuel efficiency per mile. But the new study argues that the more important metric is energy used per hour of travel.

Eric Galbraith, Earth and planetary sciences McGill professor, said in an interview with CTVNews.ca that the consistency was striking.

“There wasn’t much difference in how much time people were travelling ... it just really shows surprisingly little variation,” Galbraith said.

He added that when individuals can travel four or five hours a day, ”you don’t see it on average," because there are natural limits to how much time people can or are willing to spend in transit.

He noted that the remarkable part wasn’t the upper limit, but rather how few countries fell below it.

“The more surprising thing is that you don’t find very low values ... people like to get out and move around, and see their local environment, for at least 40 minutes a day.”

When these human tendencies combine with practical time constraints, Galbraith said populations “just tend to travel for about 1.3 hours per day.”

According to Galbraith, the stability stretches across wealth levels.

“It’s remarkable how consistent it is and how little it varies with wealth,” he said. ”It’s pretty safe to bet that people in the future are going to travel for about 70 to 85 minutes per day, not too far off.”

Energy use, emissions

The implications are significant, the study suggests. A city structured around walking or cycling uses vastly less energy per person than one built around gasoline-powered vehicles, even if those cars become more efficient.

Since total travel time stays roughly constant, the study suggests that shifting travellers into low-energy-per-hour modes becomes essential for meeting climate and energy consumption goals.

Galbraith explained the core of the study’s argument: “Often we think about energy in terms of litres per kilometers ... but what we find is that isn’t really relevant,” he said.

Distances travelled vary enormously across cultures and incomes, he said, but the time stays stable.

“You can really predict how much energy people use from the amount of energy they’re using per hour, rather than per distance.”

He offered an example of a fast, high-speed train that’s efficient per distance, but still uses a lot of energy per hour. By contrast, walking or biking uses dramatically less energy each hour, even though the travel time remains similar.

“Transport energy can vary by a factor 40 (times more) between the least amount of energy per person and the most,” he said.

Galbraith adds that the U.S. was the highest in this category with Canada being a close second.

Urban policy, next steps

The findings also point to a strategic pivot for government and urban, transportation, energy planners. Instead of prioritizing faster travel or longer distances, the study says cities should concentrate on lower-energy mobility options, such as high-quality public transport, cycling infrastructure and compact, walkable neighbourhoods.

Without such shifts, the researchers warn energy demand from transportation could continue to rise, even as vehicles become cleaner or more efficient.

“The most effective way to reduce future travel energy is to change the built environment through urban policy,” Galbraith said, stressing planners should make it “easy and convenient and enjoyable” for people to choose modes that use little energy per hour.

While the study provides a global overview, the authors note that local factors, such as urban form and cultural travel habits, still matter. Galbraith confirmed that the lowest travel-time average was Pakistan and the highest was South Korea.

As for limitations, the authors note that the analysis is statistical and broad, rather than focused on specific cities and regions.

Still, the study says the central message is clear: If people everywhere spend about 78 minutes moving each day, the most effective way to cut transport energy use is to reduce how much energy is consumed during those minutes, rather than the distance covered.

As for what comes next, Galbraith said this discovery emerged from a larger project examining how humans spend their time globally. While he isn’t continuing this specific line of transport research, he said it underscores a crucial insight policymakers can now act on.