There's a direct correlation between vehicle weight, fuel consumption, and greenhouse gas (GHG) emissions. Every pound of extra weight requires an engine to work harder, increasing fuel consumption and, as a consequence, increasing tailpipe emissions. If you reduce fuel consumption, by default, you will decrease emissions. For instance, an extra 100 lbs. in vehicle weight can reduce mpg up to 2 percent. In addition, every pound deleted from curb weight is converted into revenue-generating payload.

Decreasing the weight of vehicles is a difficult challenge for OEMs, especially when mandated to comply with ever-stricter safety regulations, which require new onboard equipment, such as stability control or stiffer bodies that can withstand tougher roof crash standards. In fact, the average weight of a vehicle in the U.S. and Japan has increased by 10 to 20 percent in the last 10 years, due to safety enhancements and increased onboard content.

The new 2016 and 2025 CAFE standards are forcing OEMs to refocus on vehicle weight reduction to meet these fuel economy standards. A recent survey of the members of the Society of Automotive Engineers asked how the auto industry will meet the new CAFE regulations. The majority (61 percent) said it will primarily involve engine downsizing with power-boost technologies. Other top responses included: hybrid and electric powertrains (51 percent), downsizing vehicles (32 percent), and greater use of lightweight materials (28 percent).

Eliminating 'Rolling Warehouses'

Until these new lighter-weight vehicles enter the market, fleet managers can do their share by requiring drivers to eliminate weight that accumulates inside a vehicle. Fleet managers should institute a program to instruct drivers on a quarterly basis to remove all unnecessary items (weight) from their vehicles. Ask field managers to enforce these fuel-saving tips and discourage drivers from using their vehicles as "rolling warehouses" to carry everything they may possibly need - just in case. Over the course of a vehicle assignment, drivers accumulate a "cargo" of dated sales materials; point of sale demos; and seldom-used tools carried in trunks, storage bins, and back seats. You'd be surprised how quickly pounds add up, especially when heavy tools and materials are carried.
As an aside, In an online post, one driver wrote: "This past weekend, I cleaned out just the trunk of my car and removed the following items - golf clubs and golf shoes (18 lbs.), two large CD cases (20 lbs.), and five library books (6 lbs.). By removing these items from the trunk, I reduced my car's weight by 44 lbs., which should improve my gas mileage and fuel economy by 0.88 percent." While this may not seem like much, it all adds up, especially when coupled with other fuel economy practices.

In terms of trucks, not only are they filled with work-related materials, but they are also sometimes used for personal storage. Ask drivers to unload all excess equipment, tools, and shelving, and carry only needed items. If given leeway, drivers will carry everything they can conceivably fit into a vehicle. It is important to develop guidelines as to what may be carried in vehicles relative to tools, sales material, and payload. Not only does unnecessary weight consume additional fuel, it poses a potential safety risk and causes unnecessary vehicle wear and tear.

Although there is little fleet managers can do about this, it is interesting to note that fuel consumption has increased as U.S. workers have become heavier, according to studies by the University of Illinois at Urbana-Champaign and Virginia Commonwealth University. Americans are using 938 million more gallons of fuel annually than they were in 1960 as a result of extra body weight. Increased body weight is directly linked to decreased fuel economy. At $4 per gallon, the cost for overweight people driving vehicles amounts to $3.6 billion a year.

Other Ways to Decrease Fuel Consumption

Another strategy to reduce tailpipe emissions is to minimize idling. The worst mileage a vehicle can get is 0 miles per gallon, which occurs when it idles. Idling for long periods of time, whether at a railroad crossing or pulling off the road to make a cell phone call, consumes gas that could be saved by simply turning off the engine. Restarting an engine uses about the same amount of gas as idling for 30 seconds.

In Snow Belt regions, during winter months, ask drivers to remove snow and ice left on the vehicle, which decreases gas mileage by disrupting air flow and increasing vehicle weight. Flying snow and ice are also dangerous for those driving behind. Similarly, roof-top racks and carriers disrupt air flow and decrease fuel efficiency. Take these items off when not in use, and, whenever possible, carry necessary items to the job, inside the vehicle.

To paraphrase a cliché, it takes a "village" to reduce fleet emissions. It is critical that you make drivers energy conscious. Similar to the habit of turning lights off in unoccupied rooms, drivers should practice comparable energy conservation habits with their vehicles. If drivers cleared their vehicle of unnecessary cargo, there would be less demand on the engine, it would increase fuel economy, and reduce tailpipe emissions.
Let me know what you think.

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About the author
Mike Antich

Mike Antich

Former Editor and Associate Publisher

Mike Antich covered fleet management and remarketing for more than 20 years and was inducted into the Fleet Hall of Fame in 2010 and the Global Fleet of Hal in 2022. He also won the Industry Icon Award, presented jointly by the IARA and NAAA industry associations.

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