Fleet owners around the world continue to search for ways to reduce their environmental impact while maintaining operational efficiency, and equipment fleets at ports are no different. As critical hubs for global trade, ports rely on a variety of vehicles and cargo handling equipment — from terminal tractors to forklifts and trucks — to load, unload, and move massive containers around the clock. Historically, port operators have relied on diesel to power operations, but as air quality and emissions regulations have tightened, many ports have upgraded to alternative fuels like propane.
The Challenge of Emissions in Ports
Historically, ports consume a lot of energy and emit a large amount of greenhouse gases. In addition to massive container ships coming and going, there are large cranes and cargo handling equipment being used to load, unload, and transport containers, such as forklifts and terminal tractors. Diesel emissions from this equipment can present problems by contributing to large-scale greenhouse gas emissions and harming air quality for workers and the surrounding communities.
As port operators strive to meet stricter emissions standards and sustainability goals, a broad mix of clean, reliable energy sources is needed to maintain operational efficiency. In recent years, propane has proven itself to be an ideal energy solution for port operators to accomplish this goal.
Propane Fleet Applications at Ports
One of propane’s biggest strengths is its versatility across applications. At ports, propane can be used in terminal tractors and forklifts to move containers, as well as in light-duty vehicles to move equipment and personnel around the facility. Historically, these vehicles have all been powered by diesel engines, which have provided operations with reliable power. However, this diesel equipment also generates significant air pollution, including carbon monoxide (CO), particulate matter (PM), and nitrogen oxides (NOx). Propane engines deliver the same power and reliability with significantly reduced emissions.
Terminal tractors, also known as port tractors or yard trucks, are used at ports, distribution centers, rail terminals, and large warehouses to move semi-trailers and shipping containers. One of the most advanced propane-powered terminal tractors today is built by MAFI and is powered by PSI’s 8.8-liter engine. These propane tractors not only deliver 270 horsepower and 565 foot-pounds of torque, but they’re also certified by the U.S. Environmental Protection Agency (EPA) and California Air Resources Board (CARB) for use in mobile, off-road applications. The PSI 8.8-liter engine is certified to 0.02 grams of NOx per brake horsepower-hour, making it one of the cleanest propane engines currently available.
Propane forklifts have been a workhorse for various material handling applications for decades — and for good reason. Propane forklifts produce 94 percent fewer hydrocarbon and nitrogen oxide emissions compared to diesel and 16% fewer greenhouse gases compared to gasoline-powered forklifts (without any drop-off in payload or power). NOx emissions from propane-powered forklift engines can be less than half that of battery-electric forklifts powered by coal-powered electric grids, which are still common in many states.
Propane serves in a wide array of other vehicle applications as well, especially in light- and medium-duty vehicles like trucks that are used for day-to-day operations and transporting equipment or personnel. Today’s propane autogas engines produce 96% fewer harmful NOx emissions than diesel and have near-zero particulate matter emissions. Likewise, they are 90 percent cleaner than EPA standards and certified to the “ultra-low NOx” emissions standard defined by CARB.
Propane-Powered Microgrids
In addition to cleaner vehicles, port operators are also turning to propane to add resiliency and redundancy to their electric grid infrastructure with the help of propane-powered microgrids. Also known as “shore power” or “cold ironing”, these independent microgrids provide electrical power from the shoreline to a docked ship, allowing the vessel to maintain fundamental functions without running auxiliary engines and burning diesel fuel while in port. Microgrids can also be used to distribute electricity to port facilities and buildings.
These independent grids are also critical in case the main electric grid goes down during severe weather events or natural disasters. Microgrids ensure operational uptime, offering the flexibility to function independently or in conjunction with the main grid. Microgrids help reduce electricity transmission and distribution (T&D) losses, which average 5 percent in the U.S. And by replacing diesel generators, propane-powered microgrids significantly reduce NOx and particulate matter emissions, improving air quality in and around the port.
For light commercial microgrids (<100kW generation system), propane fuel cells can lead to near-zero nitrogen oxide and carbon monoxide emissions, as well as a 24 percent reduction in carbon dioxide emissions. For large commercial microgrids (>100kW generation system), propane fuel cells can also lead to near-zero nitrogen oxide, carbon monoxide, and hydrocarbon emissions, as well as a 16 percent reduction in carbon dioxide emissions.
Lower Fuel and Maintenance Costs
While many clean energy solutions can be costly for a business, the transition to propane is also cost effective. Historically, the price per gallon of propane has been as much as 50% less than the cost of diesel per gallon. Likewise, the upfront cost of propane terminal tractors can be significantly lower.
In terms of refueling infrastructure, propane provides even more savings. Propane refueling stations can be installed without extensive redesign, reconfiguration, or operational disruptions. Since propane is a clean energy source, the engine doesn’t require the expensive exhaust after-treatment systems diesel engines need to meet emissions standards. Propane has fewer residual contaminants in the oil that can damage engines and less carbon build-up on the valves. Users enjoy a longer lifecycle with lower maintenance costs when equipment is properly maintained.
The Dollars and Sense of Sustainability
As port operators continue to cut emissions while managing costs and maximizing operational efficiency, propane-powered terminal tractors, forklifts, light- and medium-duty vehicles, and microgrids are attractive solutions. Propane is a cost-effective, versatile, and reliable alternative to diesel power; and by integrating propane into their operation, port operators can achieve their emissions goals without slowing down operations or cutting into their bottom line. To learn more about propane power at ports, visit propane.com/material-handling-for-ports.
Jim Bunsey is the senior manager of material handling business development at the Propane Education & Research Council. He can be reached at jim.bunsey@propane.com. For more information, visit Propane.com.
