Study suggests eco-driving techniques could reduce public transit fleet fuel consumption by up to 18.7%
Transit fleets could reduce fuel consumption on average by as much as 18.7% by engaging in fuel-efficient, eco-driving best practices, according to a Public Transit Fuel Efficiency Study released by SmartDrive Systems, a provider of fleet management and driver safety systems and services.
Eco-driving best practices for public transit include smooth acceleration and deceleration; reducing excess idling; avoiding hard turning (anticipating turns and smoothly decelerating into the turn to take advantage of the bus’s forward momentum and smoothly accelerating out of it); and maintaining constant vehicle speed.
The study evaluated several hundred transit buses and drivers in multiple US locations and from various manufacturers, including Eldorado, Flxible, Gillig, New Flyer, Orion, Prevost, Nova Bus, and Thomas Built to assess the effect of driving performance on fuel consumption and determine the impact of training and in-vehicle instant feedback on improving fuel economy. Study data was compiled by SmartDrive sensors and recorders, then analyzed and training recommendations provided.
The study measured at several key indicators and driving maneuvers known to impact fuel use and economy:
- Actual fuel use: as measured in miles per gallon from the Engine Control Unit (ECU)
- Idling time: how much time was spent with the engine running while no movement was recorded for greater than three minutes
- Acceleration: the incidence, frequency and severity of quick starts and sudden acceleration during travel as measured by accelerometer and ECU
- Braking: hard braking defined by speed from the ECU, duration of deceleration and G-force effect measured by the accelerometer
- Turning: hard turning/cornering measured by speed from the ECU and G-force from the accelerometer
During the control period, the SmartDrive system recorded the following inefficient driving maneuvers:
- 17.8 hard accelerations performed on average per hour;
- 9.5 hard braking events performed on average per hour; and
- 3.9 hard turns performed on average per hour.
Real-time in-vehicle feedback on driving maneuvers and idling gave drivers the ability to adjust driving performance as it happened. Post-training performance was measured showing substantial reductions in the number and severity of hard accelerations, hard decelerations and hard turns.
With the volatility of fuel prices, reducing fuel consumption is increasingly important in controlling operating expenses for public transit fleets. Our study documented a significant opportunity to increase fuel efficiency by addressing the 84.8% of fuel waste that can be improved through softer driving. The study also shows that training and real-time in-cab feedback combine to dramatically lower the incidence of wasteful maneuvers.
Within one month, the top 25% of drivers improved their fuel economy from 3.87MPG to 4.59MPG, or 18.7%.—SmartDrive President Jason Palmer
Conclusions and recommendations for public transit fleets resulting from the study include:
The greatest opportunity in fuel efficiency comes from the way a vehicle is operated, particularly hard driving maneuvers. Identifying inefficient driving habits and reinforcing best practices leads directly to improved performance and reduced operating costs.
Providing drivers with immediate feedback in the vehicle allows them to make quick corrections and learn over time how to most efficiently operate their vehicle. Substantial week-to-week improvements indicate that drivers are adopting and adhering to eco-driving techniques that improve fuel efficiency.
For quick results, deliver additional training with constructive guidance to the drivers that show the highest number of inefficient driving events. The combination of real-time feedback and focused training drives significant and immediate impact on overall fleet fuel consumption. In this study, in less than a month, the top 25% of drivers with the greatest improvement in fuel economy reduced fuel use by an average of 18.7%, resulting in an annual average fuel savings of $3,392 per vehicle.
To further help drivers improve their fuel efficiency, SmartDrive has released a short Eco-Driving Training Video, designed specifically for public transit.