Road Transport Emission Factors

October 28, 2015
Main Image: 

The first working high level working group meeting for India Specific Road emission factor was held on Friday, 27th June 2014 at the ITC Grand Chola, Chennai. The meeting was administered by India GHG Program Secretariat and was attended by 17 members.

The meeting started with the introduction of the India GHG program. A brief presentation was made by Kiran Ananth to set the background and purpose of the meeting. This was followed by a quick round of introductions of the individual participants and their background.

The importance of emission factors for estimating the GHG emission, specific to the transport sector was highlighted. The background, objective and methodology discussed during the meeting are summarized below -

  • Background: This meeting is an initiative of the India GHG program, to arrive at country specific emission factor for transport sector, thus strengthening the Scope 3 GHG accounting. Presently, no country specific emission factors are available for road transport sector and companies are following their own indigenous approach to arrive at emission factor or using emission factor available internationally.
  • Objective:  The objective of the High Level Working Group is to arrive at Country Specific Emission Factors for emissions resulting from transport through road ways.
  • Outcome of the working group’s efforts:

Emission factor for each vehicle type as:

  • Kg CO2/lit
  • Kg CO2/km
  • Kg CO2/ ton km (where appropriate)
  • Kg CO2/pax km (where appropriate)

-  A comprehensive methodology for calculating emissions for each vehicle type

  • Methodology: In this first working group meeting, the IGHGP secretariat proposed a simple methodology for arriving at emission factors specific to the Indian environment. The methodology considers the classification of vehicle based on type, sub classification based on engine and assumption on fuel efficiency. Various challenges of adopting the methodology such as fuel efficiency, among many others was discussed in detail as summarized below.

The summary of the views and comments made by participants on various aspects of the methodology is outlined below.


The proposed methodology largely depends on the assumed fuel efficiency. This is a significant challenge and a grey area of understanding. Participants put forward their views on various points, concerns and possible alternatives for the assumption of fuel efficiency of vehicles. 

  1. Various participants stressed that the arriving on fuel efficiency values (assumption) could be very difficult, as the fuel efficiency is dictated by a number of factors such as type of road, driving habits, traffic management, etc.
  2.  The variation between the actual fuel efficiency and the published values (by manufacturers) can be anywhere between 20-80%. This is primarily because the published values are based on test conditions and vary significantly from the actual road conditions. Assumptions thus, should be made by deliberating with stakeholders and considering an uplift factor (of 20-30%) over standard values reported by automobile manufacturers.
  3. Some participants also highlighted that road conditions should also be considered for arriving at fuel efficiency for vehicles.
  4. It was also mentioned that the government is working towards arriving at a fuel efficiency standard and this will be published in the near future.
  5. The participants were also in agreement that there is a necessity to consider uplift factors for fuel efficiency, as the real driving conditions have significant variation than the testing conditions for vehicles.
  6. It was agreed upon that the fuel efficiency assumed for the vehicles should be as close as possible to the real road conditions in contrast to the ideal test driving conditions.   


  1. It was agreed that companies cannot completely rely on existing emission factors (which are based on western and European driving conditions) as the driving cycles are different for India and there can be significant deviation from the actual values. The need to determine emission factors specific to the Indian scenario was realized and participants agreed to pool in efforts to support this initiative.
  2. It was noted that various organizations such as PPAC, Central Institute of Road Transport, State Transport Corporation, India Road Congress, etc. may have worked in this space and may have data pertaining to fuel consumption by type, type of roads, etc; which could be useful for arriving at road transport emission factors.
  3.  It was also mentioned that there are various websites and automobile manufacturers who publish the fuel efficiency and thus can be referred.  


  1. It was decided that publically available data such as published average mileage for different vehicles, from various sources, such as automobile manufacturer websites, publishing houses, etc must be referred.
  2. Consensus was also reached to work with the stakeholders in order to arrive at appropriate uplift factors, which should be considered for estimating fuel efficiency.
  3. India GHG Program is to prepare a working paper outlining the proposed simple methodology based on vehicle type, engine capacity, fuel efficiency, etc.


During the meeting further action on the initiative was also discussed and following are the proposed next steps for the study -

  1. The IGHGP Secretariat will prepare a working paper on the methodology for arriving at emission factors for different categories of vehicles .
  2. The IGHGP secretariat is to refer to different sources suggested at the first working group meeting for arriving at fuel mileage for vehicles. The IGHGP secretariat will also deliberate with various stakeholders for arriving at appropriate uplift factors.
  3. The methodology, in the form of the working paper will be circulated to the working group members and the comments will be invited from different stakeholders.
  4.  The next working group meeting will be organized as a web-meeting to facilitate further deliberations on the methodology.


List of Participants

  1. Mr. Rao K N, ACC
  2. Mr. Sriram T, Ashok Leyland
  3. Mr. Sathyanandan M, Ashok Leyland
  4. Mr. Munkundan, Flexol TVS
  5. Mr. Begur R, Mahindra Logistics
  6. Mr. Singh Kulvaibhav, Shree Cement
  7. Mr. Gandhi K K, SIAM
  8. Mr. D Souza P, Tata Motors
  9. Mr. Kulkarni M B, Tata Motors
  10. Mr. Pathak Abhay, Tata Motors
  11. Mr. Subramanian, Transport Corporation of India Limited (TCIL)
  12. Mr. Himanshu, Aditya Birla Group

India GHG Program (IGHGP) Secretariat 

  1. Mr. Vivek Adhia, WRI
  2. Mr. P V Kiran Ananth, CII-Godrej GBC
  3. Ms. Preethi Gopalan Deshmukh, CII-Godrej GBC
  4. Ms. Rajni Chada, CII-Godrej GBC
  5. Mr. Atik Sheikh, CII-Godrej GBC

The India specific transport emission factors was released on 25 August 2015 and can be accessed here.