As the most common petroleum-based fuel used in commercial delivery, diesel attracts a great deal of scrutiny when it comes to sustainability. Although many beverage distribution operations continue to integrate alternative fuels and electric vehicles into their fleets, diesel remains — and will remain for quite some time — the most pervasive option for Class 3 to 8 trucks, with the fuel powering nearly 80% of medium- and heavy-duty equipment, according to the Engine Technology Forum.

With a greater focus on efficiency and emissions reduction, and advanced engine technology, diesel-powered vehicles continue to play a role in the industry’s sustainability goals.

In terms of modern engine technology, Cummins in March debuted its new B7.2 diesel engine designed for medium-duty functions like beverage delivery. The engine is automatic-engine-shutdown and stop-start-enabled to help reduce greenhouse gas emissions.

That followed Cummins’ recent introduction of the 2027 X15 engine for heavier-duty operations, which was designed to be compliant with the EPA’s and California Air Resources Board’s 2027 emissions regulations. The 2027 X15 improves on the 2024 version — compliant with the corresponding clean-air regulations for 2024 — by offering up to 4% fuel efficiency and a sculpted engine block that reduces the engine’s weight.

There’s also been an increase in use of renewable diesel, which serves a similar purpose to biodiesel as a replacement for standard diesel but differs significantly from biodiesel.

Where biodiesel is produced through a chemical reaction when fats and oils interact with methanol or other alcohols (a process known as transesterification), makers of renewable diesel achieve their objective through a process of adding hydrogen to the feedstock to strip out oxygen and other undesirable compounds. The result of that process (known as hydrotreating) is a fuel that’s chemically identical to petroleum-based diesel. That is not the case with biodiesel, which means that biodiesel might not be compatible with all engines.

Renewable diesel, on the other hand, can be used with any existing diesel engine without having to modify the engine. It also has a lower freezing point than biodiesel, which means it’s ideal for use in regions known for their harsh winters. The main drawback to renewable diesel is that it tends to be more expensive than biodiesel. But that cost could be a wash if your existing engines require modification for biodiesel and not for renewable.

Beyond the fuel and equipment themselves, efficiency and sustainability really begin with the end user. Most federal and state agencies, as well as industry trade groups, note that there are practices that fleets can and should be implementing right away. Dynamic route planning, through technology and optimal strategies is one part of that effort, as are enforcing anti-idling initiatives and strict maintenance schedules.

Additionally, fuel efficiency should be a key facet of any driver training program. Aside from idling reduction, the fleet team should be trained on topics such as optimal speed regulation, smoother, more gradual acceleration, and proper tire pressure — not to mention the fleet’s use of auto-inflation systems and low rolling resistance tires. All of those impact fuel usage.

And they eventually will impact your bottom line.