Rising temperatures and their impact on road transport costs

The time an engine spends idling is equivalent to the amount of fuel it consumes; the more idling, the higher the fuel expenditure

The beginning of September has not halted the high temperatures, and as they rise, so do costs in the road transport sector. According to data shared by FleetOwner, the transport platform Samsara reveals that engine idling increases with temperatures above average, which can lead to higher fuel costs.

Samsara analysts studied commercial vehicle data during three heat waves in Oregon, Arizona, and Washington, as well as in nine northeastern states, between June and August 2023 and June and July 2024. Using daily temperature data from the National Oceanic and Atmospheric Administration, they found that the proportion of time spent idling increases with high temperatures. In Arizona, temperature explains 84% of the variation in idling time, and in the Northeast, 88%. During a heat wave in the Pacific Northwest in 2023, idling and high temperatures showed a strong correlation, and in June this year in the Northeast, the trend was similar.

Idling costs during heat waves

The time an engine spends idling is equivalent to the amount of fuel it consumes; the more idling, the higher the fuel expenditure. Based on Samsara’s analysis, it was estimated that major carriers in the Pacific Northwest incurred an additional million dollars in fuel costs during a heat wave in August of last year, assuming an average price of $4 per gallon of diesel, with a consumption of 0.85 gallons of fuel per hour of idling during an 8-hour shift.

By the same measure, Samsara estimated that during the heatwave of June 2024, road transport companies in the Northeast spent over $4.5 million on additional fuel in just one week.

Aside from the increased fuel consumption due to extended idling times, trucks emitted more greenhouse gasses into the atmosphere. In the Pacific Northwest, commercial vehicles emitted 5.9 million pounds of CO2 more than usual. Commercial vehicles in the Northeast contributed a staggering 24.4 million pounds of emissions.

Preparing for a future with high temperatures

With the rise in heat episodes, many organizations are prioritizing adaptation: from using real-time data to develop strategies that minimize the impact of heat, to technology that provides specific solutions for idling, improving employee safety while reducing fleet emissions. Similarly, the public and nonprofit sectors are also active in planning for extreme heat; for example, the State of Arizona has appointed a Heat Protection Chief, and the Adrienne Arsht-Rockefeller Foundation provides resources for developing action plans.

Although it is still early to determine if 2024 will be the hottest year on record, organizations can act now to understand and mitigate the effects of heat on fuel efficiency. For instance, they might consider implementing lighter paint on tractors to reduce heat absorption, improving cabin insulation, using auxiliary power units to power HVAC systems, among other measures.