Personal greenhouse impact calculator
This page was created on 2005/01/02
(January 2^{nd} 2005); modified 2015/08/03
For comments please email daveclarkecb@yahoo.com
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:
 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 (CO_{2})
CO_{2} is the most important manmade greenhouse gas because
of the very long time that it remains in the atmosphere. There are
other significant manmade 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.
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!
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.
Note: The constant 3.6667 is for converting kg of carbon to kg
of CO_{2}. One kg of carbon combines with 2.6667kg of oxygen
to form 3.6667kg of CO_{2}.
Use this calculator to compare driving your car with using public transport.
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 CO_{2} per passenger Km for various vehicles and
numbers of passengers

This graph shows how the amount of CO_{2} released from a car,
when figured on a per passenger basis, varies
depending on the size of the vehicle and the number of passengers.
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 CO_{2} 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
CO_{2} is released every passengerkilometre travelled.

Use this calculator to get an approximate figure of how much
CO_{2} 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
A figure of 50% (0.5) for the carbon content of ovendry
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.
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.
Cars  kg CO_{2}/vehicle km 
kg CO_{2}/person km 
V8 car or large 4WD (SUV)  0.41
 0.14
 Large 6 cylinder car  0.35
 0.12
 Medium 4 cylinder car  0.30
 0.10
 Small 4 cylinder car  0.23
 0.08
 Mini car  0.18
 0.06

In this table I have also added the third column, in that
column I have assumed twothirds of a full passenger load.
Public transport  kg CO_{2}/vehicle km 
kg CO_{2}/person km 
4050 seat bus (diesel)  1.30
 0.043
 1725 seat bus (diesel)  0.50
 0.036
 911 seat bus (diesel)  0.32
 0.046
 911 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


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.
A useful 'intercity transport emissions calculator' is at
Climate Change Solutions.
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
CaliforniaBerkeley Astronomy Department).
CO_{2} from air travel,
Air Travel Emissions (Rocky Mountain Institute).
Coalfired 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 CO_{2} released from burning a
litre of liquid fuel:
LPG
 Specific gravity of LPG is 0.52;
 Formula of LPG is approximately C_{4}H_{10};
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 C_{8}H_{18};
Molecular weight = 114;
Atomic weight of 8 carbon atoms = 96;
Proportion of carbon in molecule = 96/114 = 0.84;

Diesel
 Specific gravity of diesel is 0.85;
 Formula of diesel is approximately C_{16}H_{34};
Molecular weight = 226;
Atomic weight of 16 carbon atoms = 192;
Proportion of carbon in molecule = 192/226 = 0.85;

Conversion of carbon to CO_{2}
 Molecular weight of CO_{2} = 44;
 Atomic weight of carbon = 12;
44/12 = 3.67; ie. 1kg of carbon combined with oxygen
becomes 3.67kg of CO_{2}.
