Home The Long Haul Blog What Qualifies As An Alternative Fuel Vehicle

What Qualifies as an Alternative Fuel Vehicle?

September 29, 2023 Alternative Fuels Author: Rush Truck Centers Read Time: 9 Min

While petroleum gasoline- and diesel-powered engines are the mainstay of the commercial vehicle industry today, that may not be the case in the future. The demand for vehicles powered by alternative fuels continues to grow, especially as state and federal regulations are requiring manufacturers to meet stricter emissions standards and increase fuel efficiency across the board. Federal tax incentives and grants are also encouraging buyers to consider alternative fuel vehicles over conventional options.

There are many types of alternative fuels available today, each with its own benefits when it comes to reducing emissions and availability. Plus, continued research and investment in infrastructure guarantee that advancements and new options are on the horizon.

Types of Alternative Fuel Vehicles

The U.S. Department of Energy currently recognizes more than a dozen alternative fuels under the Energy Policy Act of 1992, which encourages the use of alternative fuels, aims to reduce dependence on petroleum gasoline and diesel fuels, and improve air quality. Alternative fuels defined in the Energy Policy Act include:

  • Electricity
  • Natural gas
  • Propane
  • Hydrogen
  • Biodiesel (B100)
  • Gasoline blends made up of 85% or more of methanol, denatured ethanol and other alcohols
  • Methanol, denatured ethanol and other alcohols
  • Coal-derived, domestically produced liquid fuels
  • Fuels derived from biological materials
  • P-Series fuels (blends of tetrahydrofuran, ethanol, and hydrocarbon)

These fuels are designed for use in alternative fuel vehicles and advanced technology vehicles (such as hybrid, fuel cell and specialized electric vehicles) and are currently primarily used by the government and commercial fleets. However, expect the usage of and demand for alternative fuels to increase in the coming years as stricter regulations are put into place regarding emissions from petroleum diesel and gasoline vehicles.

1. Electricity

Electric vehicles (EVs) are increasingly available and are considered alternative fuel vehicles under the Energy Policy Act of 1992. EVs can generally be broken into three categories: all-electric vehicles, plug-in hybrid electric vehicles (PHEVs) and hybrid electric vehicles (HEVs). All three typically produce lower tailpipe emissions than conventional vehicles, and zero tailpipe emissions when running only on electricity.

  • All-Electric Vehicles: Also called battery electric vehicles (BEVs), all-electric vehicles have a battery that is charged by plugging the vehicle into a charging station. Driving ranges vary from 150 to 400 miles.
  • Plug-In Hybrid Electric Vehicles: PHEVs have both an internal combustion engine and an electric motor that uses energy stored in a battery. To charge the battery, PHEVs must be plugged into an electric power source. They can travel between 20 and 40 miles on electricity alone and then will operate solely on gasoline.
  • Hybrid Electric Vehicles: HEVs have an internal combustion engine and one or more electric motors powered by a battery. Gasoline powers the internal combustion engine, and the battery is charged through regenerative braking, not by plugging it in.

Examples of commercial all-electric vehicles:

2. Natural Gas

Natural gas is a readily available fuel that is used in 175,000 vehicles in the U.S. and around 23 million vehicles worldwide. Whether produced naturally underground or man-made using methane, natural gas must be processed into compressed natural gas (CNG) or liquified natural gas (LNG) before being used in vehicles. Medium- and heavy-duty natural gas vehicles are currently available from OEMs, or qualified system retrofitters can convert many vehicles to run on natural gas using aftermarket conversion systems. Learn more about natural gas vehicles and engines here.

Both CNG and LNG are clean-burning and considered alternative fuels under the Energy Policy Act of 1992. When used as fuel, natural gas offers a small to moderate reduction in life cycle greenhouse gas (GHG) emissions when compared to conventional fuels. When comparing the life cycle emissions of the two types of natural gas, CNG and LNG are nearly identical.

Examples of commercial vehicles with natural gas capabilities:

3. Propane

Propane, also known as liquified petroleum gas, has been widely used worldwide for decades with the Propane Education & Research Council reporting nearly 60,000 certified propane vehicles in the U.S. today. Many propane vehicles are used in fleet applications, such as school buses, step vans and shuttles. Propane has a lower carbon content than gasoline and diesel fuels, and tailpipe emissions from propane vehicles are comparable to those of gasoline and diesel vehicles with modern emissions controls. Many propane engines also meet optional, more stringent low nitrogen oxide (NOx) emissions standards. The Argonne National Laboratory estimates that propane reduces GHG emissions by nearly 13% compared to petroleum gasoline or diesel vehicles.

There are two types of propane vehicles: dedicated and bi-fuel. Dedicated propane vehicles are designed to run only on propane whereas bi-fuel vehicles have two separate fueling systems that enable them to run on either propane or gasoline. Both types of vehicles can be purchased from an OEM, or a vehicle can be converted into a dedicated or bi-fuel propane vehicle.

Examples of commercial propane vehicles:

4. Ethanol and Flexible Fuel Vehicles

Ethanol is a colorless renewable fuel made from corn grain (primarily in the U.S.), sugar cane (primarily in Brazil) or cellulosic feedstocks such as wood chips or crop residues. More than 98% of gasoline in the U.S. contains some percentage of ethanol, with the most common blend being E10 (10% ethanol and 90% gasoline). E85, a blend containing 51–83% ethanol, is considered an alternative fuel under the Energy Policy Act of 1992. Also called flex fuel, E85 is used in flexible fuel vehicles (FFVs), which have internal combustion engines capable of operating on gasoline and any blend of ethanol up to 83%. As of 2021, there were more than 27 million FFVs on U.S. roads.

E85 decreases emissions of CO2 and other harmful pollutants such as benzene, when compared to traditional gasoline. The Argonne National Laboratory found that corn-based ethanol reduces life cycle GHG emissions by 40% on average when compared to traditional gasoline and cellulosic ethanol reduces emissions by 88–108%.

Examples of commercial vehicles capable of running on E85:

5. Biodiesel

Biodiesel is a renewable liquid fuel manufactured from vegetable oils, animal fats or recycled restaurant grease that has similar properties to petroleum diesel and can be used in vehicles that operate on diesel fuel. In its pure, unblended form biodiesel is often referred to as B100. Biodiesel can offer considerable GHG emissions benefits, with the Argonne National Laboratory reporting that life cycle emissions for B100 are 74% lower than those from petroleum diesel.

While traditional light-, medium- and heavy-duty diesel trucks and vehicles are not considered alternative fuel vehicles, almost all are capable of running on biodiesel blends. The most common blends are B20 (6–20% biodiesel blended with petroleum diesel) and B5 (5% biodiesel and 95% petroleum diesel), which can be used in many diesel vehicles without any engine modifications. All original equipment manufacturers approve the use of B5; however, it’s important to check if your specific engine warranty approves the use of higher-level blends like B20.

Examples of commercial vehicles capable of running on B20:

  • Hino L6 and L7 with Cummins ISB 6.7L Engine
  • Hino XL7 and XL8 with Cummins L9 Engine
  • Isuzu FTR and FVR with Cummins ISB 6.7L Engine
  • Isuzu NPR-HD, NPR-XD, NQR and NRR with the Isuzu 5.2L Engine
  • Ford ® F-750 and F-650 with Ford 6.7L V8 Engine
  • Ford® Super Duty® Chassis Cab F-600®, F-550®, F-450® and F-350® with Ford 6.7L V8 Engine
  • Ford® Super Duty® F-450®, F-350® and F-250® Pickups with Ford 6.7L V8 Engine

6. Hydrogen Fuel Cell Electric Vehicles

Fuel cell electric vehicles (FCEVs) are powered by hydrogen gas. They are more efficient than conventional combustion engine vehicles and produce no harmful tailpipe emissions, only emitting water vapor and warm air. FCEVs use a similar propulsion method as electric vehicles in that pure hydrogen gas stored in a tank is converted to electricity by the fuel cell.

FCEVs and the hydrogen infrastructure in the U.S. are still in the early stages of implementation and adoption, but research is underway to expand availability. Companies currently manufacturing FCEVs include ENC (transit buses), Global Environmental Products (heavy-duty street sweepers) and New Flyer (transit buses).

7. Renewable Diesel

Renewable diesel is fuel made from fats and oils, such as soybean or canola oil, and processed to be chemically equivalent to petroleum diesel. It can be used as a replacement for or blended with any amount of conventional diesel. It is different from biodiesel in that it is completely interchangeable with petroleum diesel and can be used in existing infrastructure and diesel engines, whereas biodiesel must be blended with conventional diesel fuel at lower levels.

According to the U.S. Department of Energy, most renewable diesel is used in California due to its benefits under the Low Carbon Fuel Standard. However, the Energy Information Agency predicts that production of renewable diesel will increase rapidly in the next few years.

Renewable diesel has been shown to reduce carbon emissions by 65% on average when compared to petroleum diesel.

Alternative Fuel Truck Sales, Service and Support at Rush Truck Centers

No one is more committed to alternative fuel vehicles than Rush Truck Centers. From trained sales experts to assistance with grants and funding to parts, service and aftermarket fuel system installations, we are your source for alternative fuel vehicle sales and support.

We’ve made extensive investments in technician training and facility upgrades to help ensure that our technicians can properly and safely maintain and repair natural gas vehicles. And we make it our business to keep up to date on all state and federal emissions regulations to ensure your trucks are in compliance with EPA, CARB, Port, and designated non-attainment and anti-idling area standards.

When it comes to engine repowers and alternative fuel system installations, our Custom Vehicle Solutions and Cummins Clean Fuel Technologies divisions are industry leaders and can help ensure your retrofit installations are done correctly and safely.

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