A Leap Forward in Sustainable Trucking – the X15N Is Here

For months and months, the heavy-duty truck industry were teased “the X15N is coming, the X15N is coming! And when it does, it will be a game changer”. Well, the new Cummins X15N natural gas engine has arrived, and it’s proving true to the hype and is not disappointing. It is the first purpose-built natural gas engine from Cummins.

Technically the engine is not commercially available in Peterbilt and Kenworth trucks until this fall and Freightliner Cascadia sleeper and day cab trucks until mid-2025, but a select number of fleet operators, like Werner, Knight, Walmart and Amazon have already been putting the new engine through a tough road test over the last several months.

Those operators – and the drivers – who have been testing the new engine are impressed with what they have experienced so far with the 15-liter engine, which delivers up to 500 horsepower and 1850 lb.-ft of torque with a standard 700+ mile range. Fuel efficiency is racking up better scores than its 12-liter counterpart too, making it a powerhouse fuel agnostic platform and the first big load natural gas engine capable of handling the most demanding applications.

What is all the hype about?

Well, for starters it’s an engine that can be fueled with renewable natural gas (RNG) instead of diesel. The X15N allows for the ease of fueling a diesel truck, but with an ultra-clean alternative fuel which companies like Clean Energy provide through their 600+ stations across North America. This versatility is crucial for trucking fleets looking to transition to cleaner fuels without compromising on performance or convenient access to fuel.

RNG is a fuel made entirely from organic waste. Companies like Clean Energy work with dairy farmers to collect waste like cow manure, which is processed and turned into RNG. It’s a transportation fuel with the same properties as regular natural gas.  By capturing and processing the manure’s harmful methane emissions, RNG production at dairies prevents potent greenhouse gases from ever entering the atmosphere. And to top it off, when RNG is used as a fuel, it can reduce carbon emissions by over 300% and NOx emissions by 90% compared to diesel. This can make a significant impact in trucking companies’ Scope 1 greenhouse gas (GHG) emission reduction goals, as well as their customers’ Scope 3 emissions in transportation.

To showcase the capabilities of the new Cummins X15N engine before it becomes commercially available, Clean Energy is leasing a Peterbilt 579-day cab tractor equipped with the X15N. We are launching a “demo truck program” which allows fleets across the country to test drive the truck and experience first-hand its highly praised power and range capabilities, impressive torque and on-road performance, while of course, accessing all Clean Energy’s fueling stations to experience the ease and efficiency of fueling an RNG-powered truck.

We already know the best use for RNG is in the transportation industry. It’s an industry grappling to find effective, meaningful solutions to decarbonize not only for sustainability conscious customers in the supply chain, but to move towards alternatives which are future-proof and ensure cleaner air and a healthier planet. Now that the X15N is here, it really is the holy grail for fleet operators. It operates great, the fuel cost is less, it has lower maintenance costs, and it provides a lower carbon-intensity rating for a vehicle which usually struggles with the complete opposite. It’s the best viable option here today for those looking to move away from diesel which is already being phased out by government agencies across the country.

Feedback from early adopters and testers has been overwhelmingly positive. Drivers have praised the engine's smooth power delivery and impressive torque which make hauling heavy loads more manageable. Fleet managers are happy with the engine's fuel efficiency which ultimately translates into lower operating costs, and that drivers are finding it seamless to transition to driving a natural gas truck.

At a recent Biogas Americas conference, Patrick Campbell, Regional Sales Manager at Cummins summarized it nicely, “The 12-liter didn’t quite have enough oomph to get Cummins into most applications, the 15L does. Most over the road fleets are running 450-475 or 1650-1850 lb. feet of torque so the X15N gets us right in the ballpark. There really is no excuse anymore for fleets to say, “well this doesn’t have the performance I need, or the drivers won’t like it” that’s off the table now as it really does work well. Our trials when comparing the diesel versus natural gas torque curve is exactly the same which just reiterates the fact that this new engine really has what people need.”

Experience the power first-hand and be amongst the first to make the switch to a sustainable clean fuel. Transitioning to RNG is now more accessible and attractive than ever. Clean Energy’s X15N demo truck is available for fleets to test drive from now until 2026 – visit www.cleanenergyfuels.com/x15n to find out more.