GHG emissions primarily drive the massive changes in the earth’s climate. The impacts we are already experiencing twill only increase in years to come – more frequent precipitation, more intense wind, heat waves, flooding, wildfires, drought, ocean warming, acidification, retreating snow and ice packs, large-scale biodiversity loss, and sea-level rise.
Transportation of freight and people is the largest source of GHG in the U.S. MHD trucks represent a significant portion of that system, and we must get cleaner.
The controversy lies in deciding what a cleaner supply chain can and should include. One side touts the growth in biodiesel and truck aerodynamics as the answer. The other side just as enthusiastically endorses Zero Emission Vehicle (ZEV) MHDs (by another name: electric trucks).
Diesel and electric trucks co-existing in a cleaner supply chain is the happy medium. It’s the compromise we need to achieve a healthy future for both the supply chain industry and the planet.
Clean Diesel and Biodiesel
Clean diesel, or ultra-low sulfur diesel, is the only petroleum-based diesel gas sold in the U.S. since 2010. This type of diesel fuel emits 97% less sulfur than the traditional formulation. Sulfur is a leading contributor to air pollution.
Alternative fuels, notably biodiesel blends called “B5” and “B20” (5% to 20% diesel derived from corn or soybeans, blended with 80% to 95% clean diesel), have been used by North American truck fleets for more than two decades. An estimated 18% of truck fleets were using biodiesel in 2018 and that is expected to double by 2023.
The least expensive, lowest-emission gallon of fuel is the one that sits around. Fuel management includes optimizing the purchase of fuel at the lowest cost possible over each freight movement or maximizing the use of intermodal. Logistics organizations and shippers need to use methods that harness data to determine actual costs versus simple fuel surcharges.
Aerodynamic drag is responsible for much of fuel consumption at speed by commercial trucks. Each slight improvement in aerodynamics makes a significant difference, considering many trucks drive 125,000+ miles annually. Each 2% reduction in drag improves fuel efficiency by 1% or more.
Near-term improvements that can make significant reductions in drag include:
Trailer skirts and boat tail fairings can reduce aerodynamic drag by 25%; the skirts can increase fuel savings by more than 4 percent and the tails by more than 5%
Changing from two-tire configurations to wider tires can create another 10% gain, with additional efficiencies from tire pressure monitoring and auto-inflation systems
The American Trucking Association has found that efficient driving techniques consume 35% less fuel than inefficient techniques. Even one day of specialized driver training can make a substantial difference in fuel consumption.
ZEV MHD (Electric Trucks)
In Washington and 14 other states, 85% of heavy-duty trucks and 93% of medium-duty trucks must be electric by 2050. Of course, the #1 advantage of electric vehicles is that they have zero tailpipe emissions.
Most MHD trucks – local delivery trucks to 18-wheelers – still run on primarily fossil fuel. Research firm Wood Mackenzie estimates that at the end of 2019, just over 2,000 electric big rigs were in service and that there will be 54,000 in service by 2025.
More attention must be paid to the lithium-ion batteries used to power most electric vehicles, including trucks. Their essential ingredient is cobalt, which helps maintain charge capacity and reduce overheating. Cobalt is scarce, with 70% of the world’s supply produced in The Democratic Republic of Congo.
Experts believe that eleven million tons of spent lithium-ion batteries will find their way to discard piles by 2030. Designing batteries for re-usability is critical at this point. If not, we will run out of suitable material to meet global demand before many more years have passed. A circular economy for ZEV batteries is also necessary to ensure climate protection.
Diesel + Electric = Powering a Bright Future
Carriers and shippers alike see the benefits of moving to more efficient, even hybridized, fleets. By acknowledging that diesel and electric trucks can and should co-exist in this fuel-efficient future, both carriers and shippers will be able to meet or surpass their sustainability goals while maximizing their profitability.