Important note

For the calculators on this page to work you must allow active content. (Some browsers give the option of blocking active content.)

Personal greenhouse impact calculator

This page was created on 2005/01/02 (January 2nd 2005); last edited 2022/08/04
Contact: David K. Clarke – ©

I decided to calculate my personal greenhouse impact, and to record the data and equations I used to do it.

There are a number of components to consider in calculating one's greenhouse impact, such things as:

  • Your household greenhouse gas impact;
  • The use of your car(s);
  • Flying
  • Travel on public transport:
    • Bus;
    • Air;
    • Train;
  • Indirect greenhouse gas production: from the manufacturing of the things you buy, the production of the food you eat, and their transport to the shop where you buy them;
  • Greenhouse abating activities, such as growing trees;
I hope that you will find this page useful. Any suggestions on how the page might be improved would be appreciated; email address is above. I believe the conversion factors that I have used are approximately correct; in many cases it is imposible to have exact figures (eg. brown coal has a highly variable composition and power stations that burn brown coal vary in their efficiencies). Obviously I'd like to be informed of any errors that I might have made.

Personal greenhouse impact calculation

Please note that this page deals only with the greenhouse gas Carbon dioxide (CO2)

CO2 is the most important man-made greenhouse gas because of the very long time that it remains in the atmosphere. There are other significant man-made greenhouse gasses.

All these calculators depend on some asumptions, you should take the results as being a guide rather than being exact.

Use this calculator to find out how much carbon dioxide is released into the atmosphere following a known amount of electricity consumption. You could get your consumption from your electricity bills.

CO2 emission calculated from electricity consumpton

Where the electricity was generated in a fossil fuel fired power station

Enter values in the top three boxes and click on the 'Calculate' button.
Electrical consumption
A = KiloWatt hours
Conversion factor
B = Enter 0.45 for natural gas, 0.5 for oil, 0.8 for black coal, 1.2 for brown coal
Percentage transmission loss:
C = eg. if there is 10% loss, then enter 10
D = A * B / (1 - (C/100))
Carbon dioxide produced, D = Kg
Example calculation: A=3718, B=1.2, C=10, D=5577
This was based on my household electricity consumption in one year; 3718kWh generated by a brown coal fired power station, resulting in 4957kg (about 5 tonnes) of CO2 being released into the atmosphere.
Also, for boiling a litre of water starting at 25 degrees, A=0.118, B=1.2, C=10, D=0.18kg (or 180g).
Notes: The conversion factor depends on how your power is generated; natural gas releases the least carbon dioxide per unit of electricity generated, oil is next best, then black coal, with brown coal worst of all.

The transmission loss is the percentage of the electricity generated that is lost before it gets to your home; in general, the further you are from the power station the greater the transmission loss. For example the Queensland (Australia) Government in its Net page Energy Losses in the Transmission and Distribution Systems, states that the annual, weighted average transmission and distribution loss factor in Queensland is about 10%, and that the loss factor would be higher when demand is higher, lower when demand is lower.

More on boiling water: The minimum amount of water that a typical cordless electric jug can heat is 480mL. Every time one of these is used to heat a mug of water (about 280mL) for tea or coffee, starting from 25 degrees Celcius, I calculate that 0.018 kWhs is wasted in boiling that extra 200mL. Assuming that this electricity is from a brown coal fired power station 23g of unnecessary CO2 is released to the atmosphere. If this is done twice a day for a year we have 17kg of CO2. Who is carefull to fill a jug exactly to the minimum mark? If the jug is filled 20% above the minimum (576mL rather than 480mL), then the figure becomes 24kg of unnecessary CO2 per year - just from making two mugs of tea each day!

CO2 calculated from fuel used

If you know (or can estimate) how much vehicle fuel you have used you can use this calculator to convert that into released atomospheric carbon dioxide. Alternatively you can use another calculator to work out your CO2 based on distance travelled.

CO2 emission calculated from the fuel you use

Enter values in the top three boxes and click on the 'Calculate' button.
Fuel consumption
A = in litres
Specific gravity
B =
Enter 0.52 for LPG, 0.74 for petrol (gas) or 0.85 for diesel
Proportion of carbon in fuel
C =
Enter 0.83 for LPG, 0.84 for petrol (gas) or 0.85 for diesel
D = A * B * C * 3.6667
Carbon dioxide produced, Kg
Example calculation: A=2200, B=0.74, C=0.84, D=5014

Note: The constant 3.6667 is for converting kg of carbon to kg of CO2. One kg of carbon combines with 2.6667kg of oxygen to form 3.6667kg of CO2.

CO2 calculated from distance travelled

Use this calculator to compare driving your car with using public transport.

CO2 emission calculated from the distance you travel

For travel by aircraft, train, tram, bus, or various sized cars

Enter values in the top two boxes and click on the 'Calculate' button
Distance travelled
A = Kilometres
Emission rate
B = kg CO2/person km
Enter 0.183 for commercial jet, 0.248 for light aircraft, 0.04 for bus or 0.027 for train or tram.
(Or 0.14 for big 4WD [SUV], 0.10 for medium car, 0.06 for mini car - if three people in car;
Or 0.20 for big 4WD, 0.15 for medium car, 0.09 for mini car - if two people in car;
Or 0.41 for big 4WD, 0.30 for medium car, 0.18 for mini car - if the driver is alone.)
C = A * B
Carbon dioxide produced, C = Kg
Example calculation: A=10000, B=0.183, C=1830
BBC Science gave the following figures:
Domestic flights: 0.133 CO2 kg/km + 0.121 non-CO2 secondary effects emissions and
Long haul flights: 0.102 CO2 kg/km + 0.93 non-CO2 secondary effects emissions
This calculator works out each passenger's share of the total CO2 from each 'vehicle'.

The figures from this calculator depend on assumptions made about the number of passengers in the particular mode of transport (that is, the 'load factor'). Obviously a 40 passenger bus with only half a dozen people in it is not an efficient form of transport.

Kg CO2 per passenger Km for various vehicles and numbers of passengers
Graph - Kg of CO2 per passenger Km
This graph shows how the amount of CO2 released from a car, when figured on a per passenger basis, varies depending on the size of the vehicle and the number of passengers. (In this the driver is considered to be a passenger.)

The tall purple bar in the back row indicates that in a big 4WD (SUV) with only one passenger about 0.4kg (400 grams) of CO2 is released every kilometre travelled.

The short blue bar in the front row shows that at the other end of the scale, in a mini car with four passengers, only 0.045kg (45 grams) of CO2 is released every passenger-kilometre travelled.

CO2 abatement

Use this calculator to get an approximate figure of how much CO2 will be taken from the atmosphere by a stand of growing trees.

There is an example of the use of this calculator on About Me

CO2 taken from atmosphere by growing trees

Enter values in the top three boxes and click on the 'Calculate' button
Number of trees
A =
Average mass of each tree
B = Kg
Annual percentage growth rate (mass)
C =
Eg. if the trees will increase in mass by 30% in a year then enter 30
Note that if they increase in height by 10% they may well also increase by 10% in the two horizontal dimensions; the resulting increase in mass would probably be about 33%.
D = A * B * (C/100) * 0.25 * 3.6667
Carbon dioxide sequested, D = Kg
Example calculation: A=100, B=50, C=30, D=1375
A figure of 50% (0.5) for the carbon content of oven-dry wood (and other tree matter, eg. leaves) has been used in the calculation above. I have also used 50% for the water content of the trees. (50% of 50% = 25% carbon content of the standing trees, therefore the factor of 0.25 in the equation.) Of course these figures are very much approximations. The figure 3.6667 reflects the fact that when a tree builds 1kg of carbon into itself, 3.6667kg of carbon dioxide is removed from the atmosphere.

On my own property at Clare in South Australia, with an annual rainfall of about 600mm, I have estimated that eucalypt trees gain something like 200% increase in mass annually from about year 1 to year 5, then perhaps 100% annually to year 10. This supposes that they are not competing with their neighbours.

Greenhouse emissions by transport type

Some figures on greenhouse gas emissions from vehicles are given on this EPA Victoria page. I have reproduced these below:

In the first table I have added the third column; in that column 3 passengers are assumed, including the driver.

Carskg CO2/vehicle km kg CO2/person km
V8 car or large 4WD (SUV)0.41 0.14
Large 6 cylinder car0.35 0.12
Medium 4 cylinder car0.30 0.10
Small 4 cylinder car0.23 0.08
Mini car0.18 0.06

In this table I have also added the third column, in that column I have assumed two-thirds of a full passenger load.

Public transportkg CO2/vehicle km kg CO2/person km
40-50 seat bus (diesel)1.30 0.043
17-25 seat bus (diesel)0.50 0.036
 9-11 seat bus (diesel)0.32 0.046
 9-11 seat bus (petrol)0.40 0.057
Tram (100 passengers)1.80 0.027
Train (6 carriages, 600 passengers)11.10 0.028
Train (3 carriages, 300 passengers)5.40 0.027

Useful links and references

No longer available. An Australian greenhouse calculator, from the EPA of Victoria, Australia. This claims to be able to calculate the greenhouse impact of your home. It seemed to me to be unnecessarily complicated. I believe it to be simpler to use electrical (and gas and heating oil, if applicable) consumption records.

No longer available. A useful 'intercity transport emissions calculator' is at Climate Change Solutions.

No longer available. Relating to the carbon content of wood, "Analysis of Wood Product Accounting Options for the National Carbon Accounting System" report of the Australian Greenhouse Office.

Some of the figures used here for specific gravity were obtained from List of common conversion factors (University of California-Berkeley Astronomy Department).

No longer available. CO2 from air travel, Air Travel Emissions (Rocky Mountain Institute).

Derivation of conversion factors - technical

Coal-fired power stations burning:
  • black coal, about 1.2MWh electricity is produced from 1 tonne of coal;
  • brown coal, about 0.8MWh electricity is produced from 1 tonne of coal;

Calculation of kg of CO2 released from burning a litre of liquid fuel:
  • Specific gravity of LPG is 0.52;
  • Formula of LPG is approximately C4H10;
    Molecular weight = 58;
    Atomic weight of 4 carbon atoms = 48;
    Proportion of carbon in molecule = 48/58 = 0.83;
Petrol (gas in USA)
  • Specific gravity of petrol is 0.74;
  • Formula of petrol is approximately C8H18;
    Molecular weight = 114;
    Atomic weight of 8 carbon atoms = 96;
    Proportion of carbon in molecule = 96/114 = 0.84;
  • Specific gravity of diesel is 0.85;
  • Formula of diesel is approximately C16H34;
    Molecular weight = 226;
    Atomic weight of 16 carbon atoms = 192;
    Proportion of carbon in molecule = 192/226 = 0.85;

Conversion of carbon to CO2
  • Molecular weight of CO2 = 44;
  • Atomic weight of carbon = 12;
44/12 = 3.67; ie. 1kg of carbon combined with oxygen becomes 3.67kg of CO2.