Rightsizing Your Vehicle Fleet to Conserve Fuel

Photo of a vehicle fleet

Denver International Airport in Colorado optimized its fleet composition to include more similar types of vehicles. This reduced the number of vehicles in its fleet by 16, saving $2.2 million in replacement costs.

Fleet rightsizing is a management practice that can help vehicle fleet managers build and maintain sustainable, fuel-efficient fleets. Fleet inventories often grow over time to include vehicles that are highly specialized, rarely used, or unsuitable for current applications. By optimizing fleet size and composition, managers can minimize vehicle use, conserve fuel, reduce emissions, and save money on fuel and maintenance.

Evaluate Vehicle Needs and Use

Fleet managers should understand their fleet's daily vehicle use and needs. Most fleet managers already have a handle on their number and type of vehicles, average mileage, payloads, and fuel economy. Fleet rightsizing combines this information with a critical look at fleet operations to identify opportunities to reduce fuel use. When rightsizing, fleet managers should evaluate how important each vehicle is to the fleet’s performance by asking themselves:

  • What tasks are accomplished by each vehicle? Or, what is the drive cycle?

  • What is the daily, weekly, or monthly mileage of each vehicle? Or, what is the duty cycle?

  • Are fleet vehicles the optimal vehicle type, class, and size for the job?

  • Are there any vehicles that are no longer cost effective to operate or are no longer fulfilling their purpose?

  • Are there any vehicles that are no longer being used or have experienced a lot of downtime?

  • Can any vehicles be replaced by lighter, more fuel-efficient vehicles?

  • Are there any alternatives to owning or leasing a vehicle, such as shuttle bus services, motor pool vehicles, sharing vehicles with other offices/agencies, public transportation, or short-term rentals when needed?

  • Considering the answers to the previous questions, what is the optimal number of vehicles required to properly support the fleet’s needs?

Fleet managers should consider soliciting input from drivers when conducting a rightsizing review, as they can be very knowledgeable about how vehicles are being used to support operations. Gathering this input also gives drivers a stake in the development of rightsizing recommendations. Fleet managers can solicit input through driver surveys or face-to-face meetings to establish consensus.

A fleet rightsizing strategy should evaluate the business case of each vehicle to determine whether reassigning, replacing, or eliminating the vehicle would reduce fuel and maintenance costs without compromising fleet activities. Fleet managers often need to define evaluation criteria and rank vehicles to complete this analysis. A fleet dominated by sport utility vehicles, for example, may find that mid-size sedans can suffice with a significant reduction in fuel costs.

Fleet managers may develop their own analysis or use existing evaluation tools. The Vehicle Allocation Methodology developed by the U.S. General Services Administration is an evaluation framework that federal agency fleets use to ensure fleets are cost-effective and contain the appropriate number and type of vehicles. Learn more about this methodology in the Comprehensive Federal Fleet Management Handbook.

Make Smart Vehicle Purchases

State and Local Laws

Maine has a law requiring fleets to purchase fuel-efficient vehicles to help the state fleet conserve fuel, save money, and reduce emissions.

Fort Lauderdale, Florida, also developed fleet rightsizing and idle reduction policies to ensure that their fleet uses the most fuel-efficient vehicles while still meeting their fleet needs.

Fleet managers may decide to replace older vehicles with more fuel-efficient or alternative fuel vehicles. These purchasing strategies may help fleet managers make decisions that meet operational needs and conserve fuel:

  • Transition to Smaller, More Efficient Engines: Using smaller engines can help fleets meet operational needs without downgrading vehicle class. Some fleets choose to switch from 6-cylinder to 4-cylinder engines to help reduce fuel use and emissions. In many cases, the new, smaller engine can have nearly the same horsepower as the old, larger engine. Fleet managers can also improve fuel efficiency by selecting smaller engines with optional gearing for their application.

  • Choose Lighter Vehicles: When purchasing new vehicles, look for opportunities to reduce vehicle weight. Lightweight materials, such as aluminum frames, and smaller components can reduce a vehicle’s fuel consumption. For example, a 10% reduction in vehicle weight can improve fuel economy by 6%–8%. Also, try to avoid unnecessarily large body configurations and heavy accessories.

  • Use Alternative Fuels and Vehicles: Alternative fuel and fuel-efficient advanced vehicles can reduce a fleet's fuel use, making them economical options for many fleets. Cost savings from vehicle maintenance, operation, and fuel use often offset higher purchase prices.

Fleet managers can blend the strategies that will provide them the greatest benefit.