February 2023
Why is the Transportation Energy Institute so focused on identifying paths to lower transportation carbon emissions? Because that is the direction global leaders in government, finance and business are driving the market (yes, pun intended). At this point, whether you agree with the direction or not is increasingly irrelevant. Policymakers, investment houses, vehicle manufacturers, energy producers – they are all exploring options to decarbonize transportation. Yet, their preferred approaches often differ dramatically and those who blindly adhere to a single idea can impede meaningful progress. If the market is to successfully reduce carbon emissions and preserve consumer access to affordable and reliable transportation, we should be pursuing and adopting a variety of solutions that build upon one another and help us transition to a future transportation system that benefits everyone.
Carbon Cycle
First, it is very important to understand what nut we are trying to crack. Atmospheric concentrations of greenhouse gases (GHGs) have been steadily rising since the 1960s and global emissions are up more than 60% since 1990.
Why do we care? Because there is evidence to demonstrate that GHG (most often referred to collectively in the common discussions as carbon dioxide equivalent, or CO2e) concentrations in the atmosphere can influence the world’s climate in ways that may be detrimental. CO2e emissions caused by human activity (a.k.a., anthropogenic) is estimated by the United Nation’s International Panel on Climate Change to account for 5% of CO2e emissions and, of that share, the U.S. is responsible for 13.9% of which 33% comes from transportation. While 5% may not seem like much to some, most scientists consider that level of emissions to be a big deal and this perspective is leading the development of decarbonization policies and strategies.
With respect to these policies and strategies, time is of the essence. This is largely because when these GHGs enter the atmosphere they settle in for a long winter’s nap. When we consider the fact that CO2 can remain in the atmosphere for 100 years, we begin to understand its significance. If we mitigate a ton of CO2 emissions now, it will have a longer-term benefit to the environment than waiting 10 years to do so, which is why taking a multi-pronged approach to transportation carbon mitigation is important.
ZEVs – A Critical Component of a Strategy
In the effort to reduce transportation-generated carbon emissions, many have chosen to pursue the market’s transition to zero emission vehicles, or ZEVs. These are most often defined as battery electric vehicles (BEVs), fuel cell electric vehicles (FCEVs) and in some cases plug-in hybrid electric vehicles (PHEVs). In the first two cases, these vehicles emit no GHGs during their operation, which has earned them the label of ZEV. They derive their power from the electricity grid or hydrogen, both of which have the potential to emit very small amounts of carbon on a life cycle basis depending upon their method of generation.
Strong advocates for BEVs are confident the electricity grid will transition away from fossil fuels like coal and natural gas and rely much more heavily on wind and solar, thereby reducing the life cycle carbon emissions that could be attributed to BEVs. And while they are most likely right, today this is not necessarily the case and electric power contributes 31% to the U.S. inventory of anthropogenic CO2e emissions. Once electricity generation does transition and dramatically reduces its CO2e emissions, BEVs will be a significant factor in reducing transportation GHG emissions. You can see in this graphic the promise of BEVs operating in low carbon electricity markets today.
However, it will take decades for ZEVs to gain sufficient market share to leverage this cleaner energy to mitigate transportation CO2e emissions. As the following chart shows, in a hypothetical scenario in which all U.S. light duty vehicle sales are required to be ZEV in 2035, the market would likely only convert 16.5% of vehicles in operation to ZEV by that time. This would leave 83.5% of vehicles in 2035 still operating primarily on liquid fuels used in combustion engines with a potential life expectancy of longer than 20 years. This means that BEVs and a cleaner electricity grid will not be able to significantly cut transportation-related CO2e emissions for many years to come, resulting in increased atmospheric concentrations that will linger for another 100-plus years. Near-term reduction tools are absolutely essential while ZEVs gain market share.
Liquid Fuels as a Strategy
The promise of ZEV technologies and their ability to reduce CO2e emissions should not be underestimated – the vehicle technology is exceptional and when these vehicles gain market share and are able to leverage a lower carbon energy source, they will contribute tremendous value to decarbonizing transportation. In the meantime, however, the sector must make strides to reduce carbon from the existing vehicle and energy system. And the best way to reduce carbon emissions from the transportation sector is to address the carbon intensity of the fuel – which will benefit both new to market vehicles as well as those already in operation.
And the opportunities to achieve meaningful carbon reductions from the lifecycle of the fuel are significant. The following chart demonstrates the possibilities when we simply consider existing biofuels and their ability to reduce CO2e emissions.
But it does not stop there. There are a variety of other fuel options that can reduce carbon emissions, as well as process improvements upstream that can lower the final fuels’ carbon intensity. From leveraging renewable energy to power petroleum and biofuels refineries to reduced carbon land use management practices for biofuel energy crops to carbon capture utilization and sequestration – there is a lot of carbon that can be removed from the system which will positively affect GHG emissions from transportation.
In fact, according to an upcoming Transportation Energy Institute report, through 2050 biofueled internal combustion engine vehicles are projected to account for as much as 76% of cumulative U.S. vehicle GHG reductions, even with the increase in market share of ZEVs. This is a significant contribution to lower remissions from the transportation sector and could be even more impactful if changes were made to capitalize on upstream carbon mitigation strategies, increase the contributions of biofuels to the fuel pool and encourage engine manufacturers to continue leveraging new techniques to improve their fuel efficiencies.
Together for One Purpose
There seems to have developed a bifurcation in the world – you are either pro-BEV or pro-ICEV. You are either for a rapid transition to electrification and against liquid fuels or the exact opposite. The problem with this situation is that it should not be an either/or situation – we need both.
Lower carbon fuels coupled with improved efficiency internal combustion engines can deliver near term and meaningful reductions in transportation-related carbon emissions. Increasing the market share for ZEVs while lowering the carbon intensity of electricity generation and increasing the production and availability of green hydrogen is critical to address the carbon emissions that cannot be mitigated by liquid fuel and engine improvements. We must play the short game and the long game – mitigate carbon where we can when we can as efficiently as we can, plan for technological advances in the future and not vilify strategies that don’t fit neatly into our bifurcated buckets.
This new report to be released by the Transportation Energy Institute in the coming months dives deep into the importance and opportunities to reduce carbon emissions from combustion engine vehicles. It will serve as a basis for meaningful dialogue within industry and government to identify strategies that will simultaneously reduce emissions while ensuring continued access to affordable and reliable transportation for all consumers within all communities.
We can make great progress if we set aside our pre-conceived notions about what is “the answer” and open our minds to collaboration, cooperation and innovation – it will be amazing what we can accomplish together in pursuit of a common objective.