Carbon Reporting: How to calculate a company’s emissions from employee commuting

Submitted by: Amanda Botes, Wednesday, May 2, 2012

Employee commuting emissions are those generated from employees travelling from their homes to work and back each day.   For many companies these emissions can form a large percentage of their emissions and should be recorded under their Scope Three emissions in their carbon reports.

This article provides guidance on how to calculate an organisation’s emissions from employee commuting in a carbon footprint report and is based on the Green House Gas Protocol and scope three supplement.

Calculating emissions from employee commuting

Employee commuting emissions are recorded under Scope Three emissions  as they are considered indirect emissions. According to the GHG Protocol it is not compulsory for organisations to report on their Scope Three emissions. However, it is recommended that those Scope Three emissions that are significant or relevant to a company’s operations are included in the report. In cases where companies have a large work force, recording emissions from employee commuting is advised.

Individual employees generally use the same mode of transport daily so extrapolations can be made for the year. However if greater accuracy is required a spreadsheet can be created where employees fill in their daily commuting. Ideally every employee should be included in the calculation but in the case of very large organisations a representative sample of the workforce can be taken.

To calculate the emissions from employee commuting the following information is required:

  1. Form of transport
  2. Distance travelled
  3. Emission factor for form of transport.  (The emission factor is the amount of CO2 equivalent emitted per km for that particular form of transport).

Example:  The example below is of a fictitious company, Dream Company.  The example shows two employees and the way that they travel to work daily.

Dream Company Employee Distance from home to work (one way) Mode of transport Comments
A 30km Bus  
B 15Km Medium diesel car Travels with a friend (therefore = two people in one car)

 

The following emission factors were used to determine the employee commuting emissions from Dream Company Employees A and B. Some emission factors have been worked out per passenger and others are per kilometre travelled. The emission factor for a bus is per passenger kilometres travelled whilst the emission factor for the diesel car is per kilometre travelled, therefore the distance travelled in the car should be divided by the number of people in the vehicle.

Mode of transport Emission factor
Bus 0.0863 kg of CO2 equivalent per passenger kilometres travelled
Medium diesel car 0.18095 kg of COequivalent per km

 

Daily employee commuting emissions

The calculations below demonstrate how to calculate the daily emissions associated with each employee.

Daily Employee Commuting Emissions from Dream Company Employee A:

(Distance travelled x2 [to account for the return distance]) x emissions factor = employee commuting emissions

(30km x2) x 0.0863 kg of CO2 equivalent per passenger kilometres travelled = 5.178 kgs of CO2 equivalent per day

Daily Employee Commuting Emissions from Dream Company Employee B:

(Distance travelled x2 [to account for the return distance]) /2 (Number of people in the vehicle) x emissions factor = employee commuting emissions

(15km x2)/2 x 0.18095 kg of CO2 equivalent per km = 2.71425 kgs of CO2 equivalent per day

Annual employee commuting emissions

To determine the total emissions produced by each employee for the year, daily travel must be multiplied by the number of working days in the year, taking into account leave and holidays. The number of leave days would be dependent on the actual organisation. The total number of working days for Dream Company is shown in the table below.

Number of weekdays in a year 260
Number of leave days 15
Number of sick days 10
Number of public holidays 10
Total number of working days for 2011 225
 

 

The total employee commuting emissions for 2011 for the sample is shown in the table below.

Dream Company Employee Total employee commuting emissions for 2011
A 5.178 x 225 = 1165.05 kgs of CO2 equivalent
B 2.71425 x 225 = 610.70625 kgs of CO2 equivalent
 

 

Each employee’s emissions would be calculated using the same method and added together to determine the total employee commuting emissions for Dream Company for the year.

Some common emission factors for employee commuting are recorded below:

Type of Transport Units kgs COe Source
Small petrol car Kilometres

0.17112

Defra 2011 guidelines
Medium petrol car Kilometres

0.21209

Defra 2011 guidelines
Large petrol car Kilometres

0.29907

Defra 2011 guidelines
Small diesel car Kilometres

0.14503

Defra 2011 guidelines
Medium diesel car Kilometres

0.18095

Defra 2011 guidelines
Large diesel car Kilometres

0.24329

Defra 2011 guidelines
Bus Passenger kilometres travelled

0.0863

Defra 2011 guidelines
Train Passenger kilometres travelled

0.05649

Defra 2011 guidelines
Minibus Taxi Kilometres

0.29907

Defra 2011 guidelines

As there is no emission factor for minibus taxi’s the Emission Factor for Large Petrol Cars above 2.0 litres in the UK can be used.

 

Amanda Botes