Natural gas is the least expensive internal combustion engine fuel available and has the smallest carbon footprint. However, these advantages are offset in some drive/duty cycle applications by both high conversion and infrastructure costs. If you already have natural gas fueling infrastructure, or if the quantity of fuel consumed at a given location is enough to justify the investment required for a captive facility, natural gas can generate major savings.
Credit: Paul Abelson Natural gas is the least expensive internal combustion engine fuel available and has the smallest carbon footprint. However, these advantages are offset in some drive/duty cycle applications by both high conversion and infrastructure costs. If you already have natural gas fueling infrastructure, or if the quantity of fuel consumed at a given location is enough to justify the investment required for a captive facility, natural gas can generate major savings.

Energy/fuel accounts for much of fleets’ total operating budget, so you’re probably always looking for ways to reduce energy costs. Fortunately, you have basically two options: consume less energy or switch to a lower-cost source.

Unfortunately, implementing the latter is complex due to the nearly limitless configurations and uses.

First, you have to maintain service during any conversion process. You also may have to relocate vehicles on an emergency, short-term, or permanent basis.

Funding is another potential hurdle.

Converting to different fuel could require significant capital expenditures, one-time expense payouts, and/or ongoing supplemental maintenance and operating costs. Even if funding is readily available, you might need to prove an acceptable return on investment (ROI) within a reasonable payback period.

Here’s how to maximize your fleet’s energy budget:

1. Analyze Drive and Duty Cycles

Most of the processes and technologies for lowering fuel costs are sensitive to drive and duty cycles. The terms are often used interchangeably, but they’re actually two separate measurements.

Drive cycle is how much a vehicle or piece of equipment is used:

  • Average speed
  • Amount of incidental idling time
  • Power export time (PTO operation, etc.)
  • Number of starts and stops per cycle
  • Longest average continuous running time per cycle.

Duty cycle is how the vehicle or equipment is used, and looks at:

  • Length of average operating cycle
  • Number of operating cycles per period
  • Total miles driven per measurement period
  • Percentage of loaded versus empty operation
  • Percentage of on-road versus off-road operation.

Generally, the effectiveness of energy reduction technology is closely related to a fleet’s drive cycles. Therefore, you can use drive cycle data to identify appropriate technologies. Then, use duty cycle data to determine if the projected savings associated with an alternative will cover the investment and provide the desired ROI.