It’s getting increasingly challenging to write about alternative fuels without mentioning electric vehicles (EVs) ― see, we’ve already failed. But there are still many viable options that don’t involve charging a battery and there’s been quite a bit of progress on many of those fronts.

Propane

Back in the spring, a new propane direct-injection fuel system made its debut in a GM Silverado pickup at the annual ACT Expo in Anaheim, Calif. The system was developed through a partnership among fuel systems technology supplier Stanadyne, Katech Engineering and the Propane Education & Research Council (PERC).

The system marries Stanadyne’s direct-inject fuel pump with vapor lock technology and injector system with Katech’s vapor lock inhibitor, creating what PERC says is the industry’s first medium-duty engine capable of delivering propane Autogas up to 200-bar pressure directly into the combustion chamber.

During a lengthy performance and durability test, the system effectively demonstrated its compatibility with existing engines. When compared with diesel, propane can reduce nitrogen oxide emissions by up to 96% and can lower carbon dioxide emissions by 5 to 10%, according to PERC.

In the U.S. Department of Energy’s most recent Alternative Fuel Price Report, the price for propane was $3.33 a gallon, versus $3.55 for diesel. The average price for gasoline was a bit lower at $3.06 per gallon.

Natural Gas

We’ve been talking about compressed natural gas (CNG) and, to a lesser extent, liquid natural gas (LNG) for many years now, but the latest buzz has been around renewable natural gas (RNG).

RNG, as its name suggests, is a renewable fuel produced from methane that’s released when organic waste breaks down. Essentially, production facilities capture methane that would otherwise be released into the atmosphere as a greenhouse gas. The origin points for the organic materials that are ultimately converted into RNG can be, for instance, landfills, wastewater treatment plants, livestock farms, organic waste management operations and food production facilities. The conventional forms of natural gas are extracted from underground sources, usually through fracking. RNG can be used as a substitute for CNG or LNG, or blended with them.

One of the big providers of CNG and RNG has been Trillium, which recently rebranded as Love’s Alternative Energy. It’s part of the Love’s Family of Companies, known for the Love’s roadside travel centers across the country.  

Biodiesel and Other Biofuels

In June the U.S. Environmental Protection Agency (EPA) introduced a set of new renewable standards to enhance American energy security and help support the country’s farmers.

The EPA measures volume requirements in terms of renewable identification numbers (RINs), with one RIN equating to one ethanol-equivalent gallon of renewable fuel. For cellulosic biofuel — the type of fuel produced from the cellulose, hemicellulose and lignin present in plant matter — EPA has posted a requirement of 1.3 billion RINs for 2026. That escalates to 1.36 RINs for 2027.

For biomass-based diesel — diesel made from organic matter like vegetable oil, animal fats or recycled grease — the goal is 7.12 billion RIN for 2026 and 7.5 billion RIN for 2027. And, for advanced biofuel — fuel created from non-food sources such as algae and forestry waste — it’s 9.02 billion RIN for 2026 and 9.46 billion RIN for 2026.

The next few years should be critical in terms of the adoption of alternative fuel technologies, and it'll be worth checking back before the end of the decade to gauge what kind of progress our industry is making toward a greener future.