The American trucking industry, and the larger transportation sector, are the biggest contributors to carbon emissions in the United States. Almost $105 billion is spent on diesel fuel each year for the trucking industry, and while there have been many efforts to curb usage, the demand is still high. Even with the dramatic social and economic impacts of COVID-19 during this year, transportation and logistics demand has been booming with online orders rising across many business sectors.
The standard heavy-duty trucks on the road today can only achieve a fuel efficiency of 7 miles per gallon (MPG). Even with new aerodynamic technology, fleet efficiencies, and improvements in driver behavior, there is still a lot of room for improvement. The desire for cleaner and more environmentally friendly alternatives to petrochemicals has pushed interest in alternative fuels to an all-time high. In addition, many local, state, and federal mandates and incentives are being created to foster greater change among businesses and consumers alike.
In order to better understand how the trucking industry may adopt some of these new capabilities, we’ll take a deep dive into six of the most promising alternative fuel sources. Each has its own strengths, challenges, and unique value propositions to offer the industry. These alternative fuel sources and technologies have the true potential to dramatically shift the trucking industry toward a cleaner future.
In this guide, we’ll discuss:
The Energy Policy Act was passed in 1992 and sought to define alternative fuel types within the United States. This was done as part of an effort to reduce the reliance on petroleum, and since this time a number of potential alternative fuel sources have been introduced. These fuels include the use of:
Some of these fuels have already started being implemented in commercial trucking vehicles, while many others are in the early stages of development. A number of challenges arise when converting heavy-duty truck engines and equipment for use with alternative fuels. Since many of the technologies required to make a shift are unproven, a great deal of research and testing is being done to better understand the impact that new fuels and hardware would have on truck fleet operations. Some of these considerations include:
Because many of these factors can only be fully understood during large-scale testing with an actual fleet of vehicles, many truck manufacturers and fleet operators have taken an active role in assessing new fuel types.
While greater efficiencies and lower operational costs are a high priority for any fleet operator, there are also many guidelines and regulations that are driving change within the trucking industry. Federal agencies such as the Department of Transportation (DOT) and Environmental Protection Agency (EPA) play a significant role in influencing policies related to the use of fuels in the trucking industry. In addition, there are many state governments that are taking an active stance in developing novel energy policies.
In particular, the Energy Independence and Security Act of 2007 has been a major driver in furthering debate about the use of alternative fuels and the potential social, economic, and environmental impacts. These are a few of the public policy topics that are of particular interest to the trucking industry.
With policies that seek to reduce US dependence on foreign oil sources, there is a significant benefit to considering alternative fuels. These fuels can directly decrease oil demand by replacing the fuel source outright or reducing the need by utilizing a blend of fuel materials. There are also many opportunities for locally sourcing alternative fuels that can reinforce a domestic supply chain. This helps reduce global influences and can give fleet operators more control over their fuel costs and risk management.
There is a limited amount of oil and many other natural resources on the planet, and alternative fuels represent an opportunity to use renewable resources. A renewable resource must be derived from renewable biomass that is derived from lands that have already been cultivated. Fuels such as biodiesel and ethanol fit into this category and help promote sustainability and a reduced environmental impact for the industry.
With recent understandings in the science of global warming, nearly every major country is seeking to reduce its greenhouse gas emissions. Many government agencies have created targets for reduction that must be met before a new fuel production facility can be opened. Recent updates to these regulations have started to focus on specific targets based on each type of alternative fuel. For example, the second Renewable Fuels Standard (RFS 2) calls for a 60% reduction in emissions for cellulosic biofuels as compared to petroleum-based fuels.
These public policy mandates have certainly gotten the attention of industry experts and truck manufacturers. As you will see in the remaining sections of this guide, a number of promising alternative fuels are being developed for widespread use in the trucking industry.
One of the most widely established alternative fuels in the trucking industry is ethanol. Also referred to as grain alcohol, ethanol can be generated from plant materials such as corn. More than 98% of gasoline in the U.S. already contains some amount of ethanol. There are several ethanol-gasoline blends that are available, the most common being E10, E15, and E85, with the number referring to the percentage of ethanol content.
One major benefit of ethanol is that it contains a higher octane rating than gasoline, leading to excellent engine performance. It is also renewable with a production output that can be supported domestically. Ethanol would have a major impact on the trucking industry if there was the widespread adoption of higher-concentration ethanol blends. In order to do so, much greater amounts of farmland would need to be dedicated to the production of corn and other feedstocks that could be used for ethanol production. These economics are currently the major reason why it is hard to expand ethanol use far beyond its current rate.
Biodiesel, which is a blend of soybean methyl esters, has many of the same supply chain benefits as ethanol. It can be produced from domestically grown soybeans and reduces the carbon output of engines when blended with traditional diesel fuel. The biodiesel also helps to lubricate an engine, which can help extend equipment lifetime and performance.
The biggest challenge to a large-scale biodiesel conversion is the storage and delivery of the fuel. At temperatures below 45°F, biodiesel can develop the consistency of a thick gel and clog supply lines and fuel filters. For comparison, traditional diesel fuels have a cold filter plugging point below 0°F, providing a much larger buffer for potential clogging issues. This makes biodiesel a suitable fuel in regions with temperate climates and in other small-scale applications but would require significant technology improvements to be viable for heavy-duty truck fleets.
The interest in electric heavy-duty trucks is gaining significant momentum after recent announcements from Tesla and other leading vehicle manufacturers. There are two basic types of electric vehicles (EVs) that are of interest to the trucking industry: battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs). Within the consumer car industry, PHEVs have become very popular, and there are now new light-duty truck models entering the market.
Battery electric vehicles, which are considered all-electric, would not have a diesel or gasoline fuel component but would run completely on electricity. This technology benefits from greater energy efficiency and comparable power output when compared to current diesel powertrains. The biggest challenge facing manufacturers is the limited range of current BEVs, especially for heavy-duty applications. For widespread adoption of BEVs to occur, there will need to be advancements in battery technology combined with a nationwide infrastructure of charging stations. Given the major investments committed by leading manufacturers, we are likely to see a major increase in electric trucks on our roadways in the near future.
Hydrogen gas is an abundant natural resource that is highly flammable and used in many industrial applications. Another type of all-electric transportation is the fuel cell electric vehicle (FCEV), with cells that are fueled with hydrogen. Since hydrogen is readily available, supply is not a major issue and fuel cells could be refilled quite easily in many locations.
The major drawbacks here are safety and reduced efficiency when compared to BEVs. While BEVs have an estimated 95% drive efficiency, FCEVs come in at around 59%. This gives major pause to industry executives and lawmakers when considering the major infrastructure requirements that would be needed to transport and dispense hydrogen gas as a domestic transportation fuel safely. Some states, such as California, are already using FCEVs to further determine the feasibility of using them on a larger scale.
Natural gas is used throughout the US for commercial and consumer applications and comes in two common forms: liquified natural gas (LNG) and compressed natural gas (CNG). Given the widespread use of natural gas and the fact that there are already over 1,000 fueling stations supporting natural gas trucks across the US, the fuel cost is about $2 per gallon cheaper than diesel. In addition, natural gas is a much cleaner fuel than petrochemicals with a reduced greenhouse gas output of up to 90% for some compounds.
A barrier to transition is the significantly increased cost that is required to retrofit heavy-duty trucks for natural gas consumption. The vehicle cost can nearly double, which makes long-term operation a major concern. In addition, natural gas leaks can be costly and toxic, which makes handling and transportation another important consideration. Even with these challenges, the number of available natural gas fuel stations throughout the US is growing. Some estimates show that nearly a third of all vehicles sold may use natural gas as a fuel within the next 25 years.
Propone, derived as a byproduct of natural gas and petroleum production, is used as a combustion fuel in many industries. This material offers similar benefits to natural gas and the other fuels mentioned in this guide. There is a plentiful supply of propane gas, which has a lower cost-per-gallon versus diesel or gasoline, with reduced output of greenhouse gasses. This is especially true for nitrogen oxide (NOx), which many state governments and the EPA are looking to reduce from current levels.
The potential adoption of propane as a widespread fuel for the trucking industry suffers from a lack of differentiation. It simply does not offer significant cost or efficiency benefits from other alternative fuels. Propane also has a lower power energy density when compared to diesel, which offsets some of the fuel cost benefits. For some local applications, such as the operation of school bus fleets, propane has proven to be a popular and viable fuel source. There are still some barriers to adoption in the trucking industry, but certainly enough potential remains to keep this alternative fuel on the radar.
With several promising alternative fuel sources in the pipeline, it’s likely that the trucking industry will start to experience a major overhaul within the next few years. The alternative fuel of choice, however, remains to be determined.
For more information on alternative fuel sources and technology for the trucking industry, visit the following resources: