The Truth on Why Diesel Is Still the Best Option for Heavy Duty Trucking


heavy duty trucking

MANY OF US who work in the transportation and logistics industry are perplexed by the federal sustainability mandates for 2028 and beyond, the burden these initiatives will place on trucking and freight delivery in the United States, and the hype surrounding the many technological advancements planned for meeting these requirements. Those announcements cover a range of proposed solutions to global warming, aimed directly at diesel engines, heavy truck powertrains and aerodynamics.

Terms such as electrification, net-zero carbon emissions, hydrogen, and natural gas fueling seem to occupy increasing editorial space as though they are within near-term reach as universal solutions. For long-haul, Class 8 trucks, they are NOT, and those trucks burn more than 90% of the diesel fuel used in U.S. transportation. So, what are the realistic, near-term solutions for the transportation industry that delivers more than 80% of the freight in the U.S?

in u.s. greehouse gas emissions

It is heartening that Chevron Corporation announced1 that they are investing in Low Carbon, High Fuel Economy through the 2030s and NOT in the unrealistic Net-Zero Carbon myth that has been touted as achievable in that timeframe. Their investment allocations do include research on hydrogen fueling as the lowest of their priorities. The word “unrealistic” is included in their assessment of the potential solutions touted for 2040. Finally, we have clarity in a direction that makes sense. Why is that the case?

The reality of delivering long-haul, highway-traversed freight is that the primary consideration is MOTIVE POWER. How often do we see that discussed in the average alternative fuel announcement? These proposed breakthrough solutions, in many cases, lack the long-term fuel economy and power output necessary for U.S. long-haul deliveries. Let’s look at where to get that power and get it in a sustainable, environmentally friendly way. The U.S. Department of Energy has given us some assistance in answering those questions.

energy density of fuels


The graph illustrating the Energy Density of Fuels is the primary indicator of the energy sources’ power potential. D2 diesel fuel has the highest energy density— 400% higher than compressed natural gas (CNG) and liquid hydrogen (H2). Also, not shown here, diesel engines are the most efficient power generators, delivering more horsepower than any other internal combustion engine. No wonder diesel is the most logical choice for long-haul trucks. It provides the required motive power at a reasonable cost, its fuel is readily available, and it has a high power-to-weight ratio. Now, how do we meet the mandate for sustainable power?

According to Google, sustainability means “meeting our own needs without compromising the ability of future generations to meet their own needs.” In other words, we can use the resources necessary to accomplish work if we do so in a manner that is efficient and that does not have lasting, harmful effects in the future. In the combustion of fossil fuels, we haven’t been doing so. As Chevron has announced, we CAN do so by focusing on lower carbon consumption and improved fuel economy. At SPI.Systems Corporation, we achieve those goals NOW.

average annual diesel fuel use for transportation

SPI has introduced a new diesel engine induction and combustion system called SPIER, pronounced spear, that releases enormous internal energy in diesel fuel that has been locked, unused, and wasted since the invention of the diesel. It does so in retrofits of existing engines (there are about 92 million of them in North America) and in new diesel engine applications. Its reasonably priced return on investment is expected in less than a year from fuel savings alone, plus double that amount when including maintenance reductions from cleaner combustion. It is already in use by long-haul fleets, with a two-year successful track record. In addition, it can be used on any diesel having emission controls from 2010 forward. It delivers these benefits through a new application of chemical engineering to diesel combustion, never before widely applied but now tested and proven over the past two years.

our energy and emissions proposition

The availability of SPIER is beginning to spread across the trucking industry. For 3PL providers and their transportation partners that use SPIER, both parties adopt green technology of the highest order available in volume usage without any changes in OEM designs or need for infrastructure change.

Alternative fuels will, no doubt, continue to make headlines. But the stark reality is that we are at least 20 years from a world where diesel is no longer the primary fuel for heavy-duty trucking. So, for now, SPI.Systems is focused on making diesel engine performance as clean and green as possible. We hope the transportation and logistics industry will join us on this exciting journey as we expand to include highway, rail, and nautical applications worldwide.

To learn more, please visit

Jack Schickler is President of SPI. Systems and inventor of the SPI Exhaust Reaction System.


1 Chevron triples low-carbon investment, but avoids 2050 net-zero goals. September 15, 2021. Reuters.