Impact of Driver Behaviour Management on the Energy Usage of Conventional, Hybrid and Electric Vehicles

  • Deepak Hari

Student thesis: Doctoral ThesisPhD


Rise in atmospheric CO2 emissions have sparked a global concern for environment and sustainability in the last few years. Strict regulations have forced automotive manufacturers to adopt newer technologies aimed at reducing tailpipe emissions. However, these technologies take time to be adopted by different manufacturers, and thus their effect can only be seen after a decade or so. A much cheaper and quicker method of reducing CO2 emissions (and also fuel consumption) from vehicles is to change the driving style of people, by reducing their aggressivity. The challenge is in ensuring that this improved driving behaviour persists over time to sustain the savings in fuel consumption.A driver advisory tool was developed to reduce aggressive driving behaviour. The device sits inside the vehicle and provides instantaneous audible and visual feedback to drivers on their driving style, on an ongoing basis. The device was tested on 15 vehicles and over 39,000kms worth of data was collected. An average improvement of 7.6% in fuel consumption was seen across the fleet, with drivers being 16.4% less aggressive using the device.The development and calibration of a low cost axial flux electric motor with a new Variable Air Gap technology is also discussed. Changing the air gap enabled mechanical field weakening that provided 45% increase in the maximum speed of the motor. This technology has the potential to be used in various applications, to work without the need for a gearbox.The electric motor was fitted in a fully electric vehicle used to test an updated version of the driver advisory tool. For this version of the device, drivers were also given feedback on their braking style. Effective braking enabled a 40% increase in recovering energy that would otherwise be wasted as heat. The device helped drivers achieve an increase of 32% in the distance travelled per kWh of net battery energy. This improvement was identified to be an effect of reduction in aggressive driving and increase in regenerative braking.
Date of Award12 Feb 2016
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorChris Brace (Supervisor) & Sam Akehurst (Supervisor)


  • hybrid
  • driver behavior
  • electric vehicles
  • energy use
  • engine
  • control strategy
  • axial flux
  • Motors
  • carbon dioxide
  • fuel consumption
  • testing
  • test development

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