Why Small Fleets Should Diversify Fuel — Even With Diesel Stable

Why does fuel diversification matter when diesel prices are stable?

Diesel prices eventually come back down after spikes. But for fleets running 1 to 50 trucks, the problem isn't just high prices — it's volatility, uncertainty, and how fast your fuel budget assumptions can break. Alternative fuels and electric trucks hedge different risks than diesel. Fleets with multiple fuel sources are less exposed to geopolitical oil shocks, Gulf Coast refinery disruptions, and OPEC production cuts than operations running diesel alone.

With the Trump administration pulling back federal EV and alternative-fuel mandates, fleets aren't feeling regulatory pressure to move away from diesel. But trucking companies that adopted alternative fuels early had reasons beyond compliance: corporate sustainability commitments, customer carbon-reporting demands, and now a third driver — preparing for the next oil shock. What used to be sustainability decisions are increasingly risk management decisions.

Diesel fuel prices track crude oil, a global commodity driven by wars, OPEC actions, refining capacity, and Gulf Coast hurricanes. Alternative fuels bring their own volatility, but the triggers are different. A fleet relying on a single fuel is more vulnerable to price spikes and shortages than a fleet with multiple fuel sources.

How do natural gas prices compare to diesel?

Compressed natural gas and renewable natural gas are largely produced in the U.S., which insulates them from global oil price swings. Domestic natural gas prices hover near $3 per MMBtu and are projected to stay stable due to abundant supply and pipeline infrastructure. High oil prices can encourage more oil drilling, and natural gas is a byproduct of that process.

Natural gas price spikes are driven by weather and storage, not geopolitics. The Henry Hub natural gas spot price spiked to all-time highs in late January 2026 during Winter Storm Fern, but the spike lasted about a week. Last October, compressed natural gas averaged $2.96 per gasoline gallon equivalent (GGE) while diesel was $3.74 per gallon, according to the Alternative Fuels Data Center.

One natural gas fuel provider offers fleet customers the option to lock in rates for up to seven years. That stability lets fleets approach shippers with long-term contracts without fuel surcharges — a selling point diesel operations can't match. The U.S. exports crude oil and diesel fuel, but natural gas is more local. It has to be liquefied to ship abroad. Most natural gas produced in the U.S. gets used here, and there's plenty of storage.

The new Cummins X15N engine is being called a game-changer, offering power and fuel efficiency comparable to over-the-road diesel engines. Natural gas fueling infrastructure has improved: the U.S. now has 1,385 stations dispensing CNG and 81 dispensing liquefied natural gas (LNG), according to The Transport Project. CNG stations increased 2% year-over-year.

What drives renewable diesel and biodiesel prices?

Renewable diesel is a drop-in fuel that doesn't require new equipment or maintenance facilities. U.S. renewable diesel production capacity grew from about 1 billion gallons in 2020 to more than 5 billion gallons last year, according to Donnell Rehagen, CEO of Clean Fuels Alliance America.

Renewable diesel prices are driven by feedstocks like soybean oil or animal fats, policy incentives including RIN credits through the EPA's Renewable Fuel Standard program, state low-carbon fuel standard programs, and blender tax credits. EPA's Renewable Fuel Standards for 2026 establish the highest blending volumes in history, expected to boost biodiesel and renewable diesel production by more than 60% compared to 2025. Prices are also influenced by overall diesel demand.

Volatile renewable diesel prices could happen if soybean oil prices swing sharply, if policy changes, or if supply bottlenecks develop. Biodiesel is getting attention as technology improves to allow higher percentage blends, even 100% using certain add-on equipment. Biodiesel prices are tied to similar factors as renewable diesel. Compared to renewable diesel, biodiesel has been around longer and is more widely available, especially in blends like B5, B10, or B20. It has more variability in cold weather performance and blending limits.

How stable are renewable natural gas and electricity prices?

Renewable natural gas (RNG) prices are driven by policy incentives, carbon markets, and feedstock availability. RNG pricing is tied not just to the fuel itself but to environmental credit markets and policy incentives. That means volatility is less about geopolitics and more about regulatory changes and credit pricing. In some cases, fleets can insulate themselves from volatility through long-term fuel contracts tied to specific projects.

Electricity prices are largely driven by regional supply, infrastructure, and regulation. Power is generated and consumed locally. Unlike diesel, which is tied to global oil markets and geopolitical upheavals, electricity depends on a regional mix of natural gas, coal, nuclear power, and renewables. Wind, solar, and nuclear power have high upfront costs, but once built, there's no reason for the electricity they generate to spike like crude oil and diesel.

Electricity pricing is built around long-term investments in power plants and grid infrastructure, which tends to smooth out short-term swings. For fleets, electricity can often be contracted at fixed rates, and charging can be managed to take advantage of lower-cost periods. Both natural gas and electricity can be contracted for longer terms than diesel fuel to help keep prices predictable.

What's changing with electric truck technology?

Battery technology appears to be accelerating to the point where it will soon become less expensive, lighter weight, and able to store more power. More than 1,710 solid-state battery patent applications were published globally in the first quarter, according to IP analysis firm KnowMade.

The Tesla Semi is reportedly being offered for significantly less than legacy OEM electric trucks, and with longer range. The International Council on Clean Transportation reported that in just over a year, Tesla's Semi racked up more tractor voucher applications under California's Clean Truck & Bus Voucher (HVIP) incentive program than every manufacturer combined over the previous four years.

What are the operational trade-offs for small fleets?

Alternative fuel vehicles — other than biodiesel or renewable diesel that are drop-in replacements — have a higher purchase price than diesel counterparts. But many states have their own programs to help fleets transition to lower-emission vehicles, not just California and New York. Texas and Florida have such programs too.

Your location and operations dictate what's feasible. Charging and fueling infrastructure, while improving, is not nearly as ubiquitous as diesel. For electric trucks, contingency plans must be made in case of power outages. Customer demands make a big difference. Infrastructure availability varies by region — a fleet running the I-5 corridor has more natural gas and charging options than one running rural routes in the Southeast.

Why diversification beats picking a winner

Diversifying fuels doesn't eliminate volatility, but it changes what you're exposed to. The fleets coming out ahead aren't the ones picking a winner. They're the ones building enough flexibility to adjust when things change. A 10-truck fleet running five diesel tractors, three CNG day-cabs, and two electric box trucks on local routes isn't hedging against one risk — it's hedging against three different sets of price triggers and supply disruptions.

If you've pushed fuel diversification plans to the back burner because of the freight recession or the change in federal policy, the case for alternatives isn't gone. It's shifted from compliance to risk management. Fleets that rely on a single fuel will be more vulnerable to the next price shock than fleets with multiple fuel sources.