Carbon Emission Calculation and Reporting
The carbon calculator uses commuting information supplied by Council staff to calculate the volume of carbon emissions associated with staff commuting to and from work. The results display valuable insights on commuting habits, preferred transport types, and emissions generated. These insights can help inform Council's 2026 goal to increase the use of Active, Public, and shared commute methods to 20% or more.
We use the responses collected from the two week-long survey on how employees travelled to work to estimate how much CO2 is emitted by employees’ commutes in one typical work week.
162 employees responded to the survey, sharing their mode of transport, the distance of their commute, and what days they worked on site or from home. People who carpooled also told us how many passengers were in the car with them.
Since we only have answers for one week for a portion of employees, we can’t say what the whole council’s emissions would be, but we can better understand commute patterns and the emissions that are associated with them.
CO2e emissions from employee travel =
To calculate each employee’s commute emissions, we looked at how far they travelled by each mode of transport, and used this emissions table to calculate the emissions from that travel¹:
| Mode of Transport | Emissions Factor (kg of CO2 emitted per person km travelled) |
|---|---|
| Car | 0.244 |
| Motorbike | 0.12 |
| Bus | 0.018 |
| Train/Tram | 0.029 |
| Bicycle /Walk /Run | 0 |
The total emissions caused by each vehicle by each employee during their typical work week is calculated as:
T x 2 x N x E / P
where:
T = daily one-way distance between home and work (km)
2 = multiplies T to capture the return trip to home from work
N = number of days travelled by this mode of transport in a week
E = the “emissions factor” of that mode of transport (as per the table above)
P = the number of people in the car (for carpoolers only)
Example 1 – single mode:
Employee A lives 10km from the office, and travelled by car to work 5 days a week. Their emissions would be:
Car = 10 km x 2 ways x 5 days x 0.244 kg/km = 24.4 kg
Total emissions = 24.4kg Co2 produced in the week
Example 2 – carpool:
Employee B lives 10km from the office, and travelled by car to work 5 days a week, with 1 other person in the car.
Car = 10 km x 2 way x 5 days x 0.244 kg/km / 2 passengers = 12.2 kg
Total emissions = 12.2 kg Co2 produced in the week
Example 3 – mixed mode:
Employee C lives 20km from the office, and travelled by train 2 days/week, and by car 1 day/week.
Train/tram = 20 km x 2 ways x 2 days x 0.029 kg/km = 2.32 kg
Car = 20 km x 2 ways x 1 day x 0.15 kg/km = 9.76 kg
Total emissions = 12.08kg Co2 produced in the week
¹ 2018. Transport Strategy Refresh: Transport, Greenhouse Gas Emissions and Air Quality. [ebook] Melbourne: City of Melbourne, p.4. Available at: <https://s3.ap-southeast-2.amazonaws.com/hdp.au.prod.app.com-participate.files/6615/2948/1938/Transport_Strategy_Refresh__Zero_Net_Emissions_Strategy_-_Greenhouse_Gas_Emissions_and_Air_Quality.pdf> [Accessed 11 August 2022].
What can you achieve with the Calculator?
The results from the carbon calculator provide a point-in-time snapshot of a Council's staff commute emissions. Analysing trends and patterns relating to transport modes and daily emissions will allow Council to devise strategies such as ridesharing, incentivised modes of transport, or flexible work arrangements, to name just a few.
While the formula was developed by the Greenhouse Gas Protocol Centre of Excellence, the survey and results page were built by a volunteer group of problem solvers, Civic Makers, trying to solve the question of “How can we make our communities better?” using civic-tech. We can not solve every problem related to our community at once, so we decided to build tools that support Council sustainability initiatives. Civic Makers is run by Code for Australia, an organisation that builds tech stuff that matters for all levels of government.
Why did we make this calculator?
Due to climate change, we want to use our technical skills for the public good by supporting governments in responding to the climate crisis. We believe assisting them with this calculator would be an excellent place to direct our efforts while council budgets and resources are under pressure.