Concept: Automated Fuel Efficiency Tracker/Calculator

This would either be a feature on a GPS unit, or an application for a GPS-enabled Smartphone (Windows Mobile, Symbian, Blackberry, Palm, etc), a PDA, or even a stand-alone device

User Experience

  • The user would start the application prior to departing, and would stop the application upon arriving at his/her destination
    • This process could possibly be automated by tracking whether the vehicle is moving or not, but due to restrictions such as battery life, and possible inaccuracy due to other conditions (idling, the user taking the unit with him/her, etc) this would probably be an option turned off by default
  • The user would enter the number of gallons at each fill-up, and if this filled the tank entirely or not
  • The user would get a report of calculated fuel efficiency, and estimated fuel efficiency
  • Multiple cars can be specified, in case the user drives multiple vehicles (a small car and a pick-up truck, or a truck and an ATV). This could even apply to boats.
  • The user can add additional sensors (ODB pick-up, temp sensors) to improve the accuracy of the reading
  • The user can also add in additional details every so often to track other factors of vehicle’s operation
    • The user could specify how much they spent at every fill-up, and what grade of gasoline they purchased, so that this fill-up can be compared to others in the past as far as performance and cost is concerned
    • The user can also enter in maintenance data, such as oil changes, filter replacements, spark plugs, even tire inflation, to compare pre- and post-maintenance efficiency, and perhaps even track the point where any gains seem to drop off.
  • If the device is Internet Enabled, and the user allows Internet access, the user can allow found gas prices to be uploaded to the Internet (to sites such as Gas Price Watch and Gas Buddy)
    • The converse can also happen, where the unit can list the most nearby stations and their prices
  • Perhaps a social/community service can be available on the Internet, where vehicle efficiency statistics can be uploaded and anonymously compared to other drivers in the area (in general), other drivers with the same make/model/year of vehicle (nationwide, and locally).


  • The software would keep an internal trip odometer for each trip, and an overall tank odometer for driving since last fill-up
  • The software would do some easy math to determine efficiency
  • There would be various “education” modes where if the unit detects the person has not driven more than 35-40 MPH since last fill-up, it can estimate city driving fuel efficiency
    • Same can be said for highway efficiency, or even more complex scenarios, such as driving up or down hills, or being stuck in rush-hour traffic.
    • The software could also determine fuel lost idling, by tracking when the vehicle isn’t moving for a certain amount of time (to determine if the vehicle is idling, or parked)
    • With GPS doing the tracking, there doesn’t need to be any user interaction for this.
  • With more and more accrued data, the software could also begin to estimate fuel efficiency before the person fills up, and when the software actually gets a fill-up, it can offer a comparison between its theoretical model and the vehicle’s actual performance
  • An option would be to identify added weight or number of passengers, to offer a more informed model
    • Information can also be added after the fact
    • An intelligent weight option can also be specified in software
      • The GPS unit can determine if it’s gone to, say, the grocery store, and then assume that the average weight of a person’s groceries have been added to the vehicle
  • The GPS unit can also be linked to weather service information (either by adding optional sensors, utilizing sensors already installed in the car, or information from the Internet) to develop a model of fuel efficiency versus various environmental factors.
  • The unit could also have an interface for the car’s internal hardware
    • The car’s existing on-board diagnostics port can be utilized to gather a significant number of additional details, either by way of a capture device, where data can be added in after the fact, or by way of a custom dongle which would allow wireless communication of this data (perhaps via Bluetooth)
    • Cooperation with automotive manufacturers could find cars with on-board Bluetooth offering ODB data via that Bluetooth link (if this already doesn’t exist)
  • Data could be exported to a full computer to allow additional analytical data to be presented to the user
  • The use of GPS in the software should allow for the software to determine a reasonable measure of efficiency, without any additional hardware
    • Furthermore, the software should be intelligent enough to operate with a minimum of user interaction
  • Perhaps the unit can detect if the vehicle hasn’t been moving for a certain amount of time (>5 minutes) that it has stopped, and therefore should no longer track information
    • The converse can also be used to determine when the vehicle actually begins to move.

When integrated into a navigation software (perhaps as a part of a stand-alone GPS unit, or navigation software for a smartphone), it could even be used to predict fuel consumption en route, or give an estimation of the distance capable of being traveled under current conditions (Granted, some vehicles already have this feature, but perhaps they aren’t as complex, and is a feature that many people may wish to retrofit into their existing vehicles.

This is just a brief overiew of my idea, I’m still scratching out some details. The nice thing about this, is that with some coding knowledge, someone could design a software prototype in something as easy to learn as Python and load it onto a Smartphone pretty quickly. The purpose of this post, however, is to establish a record of the concept, in the hopes that no one should appropriate it.