As record diesel prices squeeze truckers, farmers, new analysis identifies fuel-saving strategies

As diesel fuel prices climb to record highs across the U.S., raising costs for freight movement, agriculture, construction and other essential industries, the Engine Technology Forum has released new analysis based on current fuel prices identifying strategies to reduce fuel consumption and provide immediate and long-term relief from this period of higher prices.

According to the U.S. Energy Information Administration, the national average on-highway diesel price reached $6.285 per gallon Sept. 14, up nearly 69 cents per gallon in just two weeks, and almost $2.55 per gallon more—nearly 70 percent higher—than a year ago.

Industry analysts warn that tight global diesel supplies, low distillate inventories, refinery disruptions and growing seasonal demand are keeping upward pressure on diesel prices.

“Diesel is the lifeblood of the economy, powering 97 percent of the largest commercial trucks (Class 8), more than two-thirds of all farm and construction equipment, and nearly all locomotives and marine workboats,” said ETF Executive Director Allen Schaeffer. “Diesel prices have now exceeded the previous record set in 2022. At these prices, every gallon saved matters. Our new analysis—based on current fuel prices—highlights key factors that directly contribute to higher fuel costs and how to mitigate their impacts. In some cases, truckers can save over $10,000 in annual fuel costs.”

Vehicle speed

Fuel is typically the single largest operating expense for trucking companies.

A tractor-trailer-sized truck traveling at 70 miles per hour (mph) uses roughly 15 percent to 25 percent more fuel than the same truck traveling at 55 to 65 mph.

Assuming 100,000 miles annually, a truck averaging 6.6 miles per gallon (mpg) would use about 15,150 gallons, while a truck averaging 8 mpg would use about 12,500 gallons.

Higher speeds use more fuel—in this example, about 2,650 gallons more.

At today’s national average diesel fuel price of $6.28 per gallon, that translates into about $16,600 in additional annual fuel expense.

Engine idling

A heavy-duty truck engine burns one-half to 1 gallon of diesel fuel per hour at idle.

Idling for two hours a day at 0.8 gallons per hour translates into 1.6 gallons of fuel wasted, which at current fuel prices translates into $10.05.

When factoring in 2 hours a day of idling at 250 operating days a year, that amounts to about 400 gallons of fuel, or $2,512 in additional fuel costs.

According to Geotab, construction fleets commonly lose 30 percent to 40 percent of equipment productive time to idling, and telematics allows managers to identify high-idling machines, operators and jobsites.

Idling also increases engine wear and the need for more frequent maintenance.

Maintenance practices

Preventive maintenance—including oil changes, air-filter replacement and maintaining proper tire pressure—contributes to lower fuel consumption and more efficient vehicle and machine operation.

Low tire pressure is the most notorious contributor to inefficient engine operation and poor fuel economy.

According to the U.S. DOE, underinflated tires can reduce fuel economy by about 0.2 percent for every 1 pound per square inch (psi) drop in the average pressure of four tires. 

Equipment age

A new tractor-trailer-sized truck from model year 2010 or newer uses about 3 percent to 5 percent less fuel, thanks to advanced diesel engines that utilize selective catalytic reduction (SCR) and diesel exhaust fluid (DEF).

The same goes for farm machines and construction equipment from model year 2014 or newer.

While newer equipment typically costs more upfront, improved fuel efficiency and lower operating costs can help offset the initial investment.

Diversify fuels to include biodiesel, renewable diesel

Biodiesel and renewable diesel can help truckers and farmers in two ways.

First, biodiesel blends can be competitively priced with conventional diesel, particularly in regions with strong production and infrastructure.

Second, and perhaps more importantly, biomass-based diesel adds domestic fuel supply to the market, helping lessen some of the price volatility that affects diesel fuel users.

A 2022 study found that expanded biomass-based diesel production could lower diesel fuel prices by about 4 percent.

Many diesel engines can generally use biodiesel blends up to B20 (20 percent biodiesel/80 percent petroleum diesel), subject to manufacturer recommendations, and renewable diesel can be used in all diesel engines as a direct replacement for petroleum diesel.

Biodiesel and renewable diesel come from essentially the same feedstocks but are processed differently.

Some newer generations of farm equipment are able to use higher blends of biodiesel, up to B30.

At current diesel prices, using a 20 percent or higher biodiesel blend can translate into savings, depending on the price of the blend.

Biofuels also diversify the fuel supply and help cushion future volatility.

Use new technologies to work more efficiently

From artificial intelligence (AI)-based freight routing and driver-assistant technologies to telematics, connected construction machines and sites, and precision farming, a wide range of technologies can improve productivity, reduce inputs and labor costs, and improve equipment utilization—all of which can contribute to lower fuel consumption.

Explore alternatives to diesel

Natural gas and propane have not experienced the same price increases as gasoline and diesel and are readily available.

There are a growing number of options for commercial trucks, school and transit buses, and other equipment to convert to propane.

For heavy-duty trucks, natural gas offers an increasingly competitive option to diesel fuel, with increasing access to refueling facilities.

Limited electric-truck options are available, as are some models of construction equipment, both compact and medium-sized.

Factors such as access to charging infrastructure and suitable operating range are key considerations, as is the upfront cost of all-electric vehicles and equipment, which is generally higher than that of traditional engine-powered vehicles and equipment.

Electricity also has a cost that must be factored in, depending on its source and the mix of generating assets.

Learn more at enginetechforum.org.