Biodiesel Production Rebounds After RFS Volume Rule Finalized
Trucking firms can cut fuel costs with biodiesel as production picks back up following federal renewable fuel mandate clarity.
How much can biodiesel cut fuel costs for small fleets?
Biodiesel production is climbing again after the EPA finalized Renewable Fuel Standard volume requirements, giving trucking firms a lower-cost alternative to diesel at a time when pump prices remain elevated. The federal mandate sets annual blending targets for renewable fuels, and the finalized volumes give refiners and blenders the certainty they need to ramp up output.
For a small fleet, the math is straightforward: biodiesel typically trades at a discount to petroleum diesel when production is steady and supply chains are running. The RFS volume rule removes the uncertainty that had kept some producers on the sidelines earlier in the year. More supply means more competitive pricing at the rack, which flows through to what you pay at the pump or through a fuel card.
Biodiesel blends (B5, B10, B20) burn in most modern diesel engines without modification. The fuel delivers slightly lower energy density than straight diesel, so expect a 1-3% MPG hit on B20, but the per-gallon cost advantage often more than covers the efficiency loss. Mack's EPA 2027 MP13 approves B20 biodiesel, signaling OEM confidence in higher blends for newer powertrains.
The RFS finalization matters because it locks in the volume targets refiners and blenders use to plan production runs. When those targets sit in limbo, biodiesel output stalls and prices spike. With the rule now published, producers can commit capital to production, which stabilizes supply and keeps the fuel flowing to truck stops and cardlock networks.
What the RFS volume rule does
The Renewable Fuel Standard requires refiners and importers to blend a minimum volume of renewable fuels into the national fuel supply each year. The EPA sets the annual targets, and biodiesel counts toward the advanced biofuel category within the mandate. When the agency delays or revises those targets, producers hold back investment and output drops. The finalized rule removes that friction.
Biodiesel production had softened in late 2025 and early 2026 as the industry waited for EPA to publish the volume requirements. Producers need those numbers to secure financing, lock in feedstock contracts, and schedule production. The rebound follows the rule's publication, not a sudden shift in feedstock costs or refining economics.
For fleets, the practical effect is more biodiesel availability at competitive prices. Truck stops in the Midwest and Southeast, where biodiesel infrastructure is densest, are seeing steadier supply. West Coast and Northeast availability lags but is improving as production ramps.
Fuel cost relief in a high-price environment
Diesel prices remain elevated compared to pre-2025 levels, even as crude has pulled back from the $110 spike earlier this spring. Renewable diesel and RNG gained traction when Brent crude topped $110, and biodiesel is following the same pattern. When petroleum diesel sits above $4.00 per gallon in most markets, a 10-15 cent per gallon discount on B20 adds up fast for a fleet burning 5,000 gallons a month.
The fuel cost advantage varies by region and blend level. B5 and B10 trade closer to petroleum diesel because the blend ratio is low. B20 offers the widest discount but requires confirming your engine warranty covers the blend. Most post-2010 engines handle B20 without issue, but check your OEM's fuel spec before filling.
Biodiesel also qualifies for federal and state tax credits in some jurisdictions, which can lower the effective cost further. The credits flow to the blender, not the end user, but competitive fuel markets pass most of the savings through to the pump price. If you're buying fuel on contract, ask your supplier whether the biodiesel blend includes any passed-through credit value.
What changes for small fleets
If you run 5 to 50 trucks and you're not already buying biodiesel blends, now is the time to ask your fuel supplier what's available. Production is climbing, supply is stabilizing, and the per-gallon discount is real. The RFS volume rule removes the regulatory uncertainty that kept some suppliers cautious earlier in the year.
For owner-operators, biodiesel availability at truck stops is improving but still uneven. Pilot, Love's, and TA carry B20 at select locations, mostly in the Midwest. If your lanes run through Iowa, Illinois, Indiana, or Missouri, you'll find it. If you're running the I-5 corridor or the Northeast, availability is spottier. Call ahead or check the fuel finder on your truck stop app before counting on a biodiesel fill.
The fuel cost savings are modest but consistent. A 10-truck fleet burning 50,000 gallons a month saves $5,000 to $7,500 per month if biodiesel trades 10 to 15 cents under petroleum diesel. That's $60,000 to $90,000 per year, enough to cover a driver's salary or a truck payment. The savings scale with your fuel burn, so larger fleets see proportionally larger relief.
Biodiesel won't solve the rate problem, but it takes a bite out of the fuel line on your settlement statement. With production rebounding and the RFS rule locked in, the fuel is more reliable and more competitively priced than it was six months ago. If your supplier offers it, run the numbers.
