Field Trials for a Sustainable Fuel Paired with a Game-Changing Engine

June 13, 2023

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As pioneers in the renewable energy sector, Trillium Energy Solutions (Trillium) is providing solutions for innovative fleets operating across the country. In this spirit, Trillium recently announced that it is supplying renewable natural gas (RNG) to Werner Enterprises, a truckload transportation and logistics service provider, for field trials of the new Cummins X15N engine in two states. 

This marks a significant step forward in Trillium’s mission to contribute to a more sustainable future. By supplying RNG to Werner during these trials, Trillium is supporting the real-world validation of this game-changing engine paired with a dependable fuel. 

The Cummins X15N engine represents a pivotal moment for emissions reductions across the heaviest weight class vehicles and for situations where battery-electric vehicles (BEVs) may not be suitable or commercially available. Not only is this a powerful engine, offering an output of up to 500 hp, but it is also paired with the Cummins Clean Fuel Technologies fuel delivery system. Trillium and Cummins announced a collaboration in 2022 to assist customers that want to integrate alternative fuel technologies, including RNG, into their fleets by providing the information, technology, and infrastructure needed for reduced operational costs and time savings.  

The significance of the X15N engine extends beyond its technical specifications to its environmental and economic impact. This engine plays a crucial role in helping customers achieve net-zero greenhouse gas emissions, a critical target in the fight against climate change. The combination of the X15N engine and RNG is expected to drive meaningful growth of the heavy-duty natural gas truck market and provide both significant economic and environmental benefits to fleets. RNG cost savings are primarily attainable in California, although according to the State of Sustainable Fleets report, more states are adopting Low Carbon Fuel Standard (LCFS) programs that can help RNG achieve diesel parity or better. This cost-effectiveness, combined with Cummins’ 30 years of experience with natural gas, gives fleet owners the confidence to transition towards sustainable technologies without compromising operational efficiency. 

RNG offers a significantly lower-carbon option for any fleet operating natural gas vehicles. Fleets can use this sustainable, low-carbon and carbon-negative fuel as an easy replacement for fossil CNG (compressed natural gas) across vehicle types. This allows for significant reductions in lifecycle greenhouse gas emissions when operating trucks fueled with RNG, including trucks with the X15N engine. In some cases, the operation can even be carbon negative, depending on the bio-source and waste feedstock used to produce the RNG fuel.  

In addition to the advantages of RNG, the X15N offers a path towards lower emissions while also reducing the cost of adopting such technologies for fleet owners. The engine is expected to meet future emission standards, capable of achieving lower NOx levels than the 2027 U.S. Environmental Protection Agency (EPA) and 2024 California Air Resources Board (CARB) standards, while also improving efficiency by 10-15% compared to the current 12-liter engine, nearly closing the efficiency gap with diesel engines. 

The RNG that Trillium is supplying will fuel Werner’s Peterbilt Model 579 field trial truck, powered by the Cummins X15N natural gas engine, from Trillium stations in both Illinois and Nebraska. This strategic partnership and use of RNG in the Cummins X15N engine aims to lower fleet emissions, enhance performance, and reduce downtime. 

Our relationship with Werner Enterprises is essential in our long-term goal of embracing innovative fuel types. As one of the first fleets to test RNG in the Cummins X15N engine, Werner is providing valuable real-world data that will help the wider industry validate these engines before their adoption. The use of low-and even negative-carbon fuel is an essential component for any fleet to meet sustainability goals. As Love’s and Trillium continue a successful relationship with Werner, we are dedicated to expanding our retail CNG station footprint by adding more locations for customers in 2023 and beyond in several markets in the U.S. We welcome the opportunity to work with other customers considering RNG in the future to help plan successful fueling routes and even new CNG station locations. 

For more than 20 years, Trillium Energy Solutions has exceeded customer expectations by delivering superior quality, reliability, and dependability at alternative fueling stations nationwide. Trillium supplies both low-carbon and carbon-negative RNG to fleet operators throughout the U.S., currently providing RNG across 26 states. More than 65 of these locations are public-access stations and can enable fleet operators to achieve low- or negative-carbon operations today. To learn more about existing and future CNG infrastructure and utilizing or transitioning your fleet to RNG, please visit or