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About
Carbon Footprint Calculator - version 3
Complete this questionnaire to estimate / calculate your CO
2
emissions
.
Do either a quick estimation (no bills needed) or a more accurate calculation of the CO
2
and other greenhouse gas emissions that you are responsible for, as an individual, over a 12 month period.
In section 1
, you enter household data, so that items such as household heating and car use are shared between the members of your household.
In section 2
, you enter personal lifestyle and travel choices that apply to you as an individual.
This is version 3 of the calculator, superseded in 2019 by version 4, but preserved so that like-for-like comparisons are possible with previous estimates using version 3.
Read more.
Section 1
(household)
q1.
How many people are there in your household?
Notes
:
This is needed for sharing out your gas, electricity and car use between the members of your household.
You can enter a decimal, e.g. 3.5, if you have a family member who is away from home for part of the year.
more ...
q2.
How much electricity is used in your household?
Select one option:
Small house / flat (3,000 kWh)
Medium (4,800 kWh)
Large house (7,000 kWh)
Enter actual amount used from your bills
Latest reading (kWh)
Reading 12 months before
Tick the box if your electricity comes from one of the green tariffs:
Good Energy; Equipower; Green Energy Dark Green and Pale Green; LoCO
2
Energy Planet, Energy Pocket+ and Energy Pocket; Ecotricity New Energy + and New Energy; Ovo Green Energy and New Energy
kWh
tonnes CO
2
Notes
:
Electricity use is measured in kilowatt-hours (abbreviated to kWh).
To make an accurate calculation, you need to find your latest bill and the reading (in kWh) at the end of the last quarter.
Then find the bill 12 months before it and the corresponding reading.
The CO
2
emission factor for electricity is taken to be 0.527 kg / kWh [
read more
]
There is a reduction of 25% in CO
2
emissions for the green tariffs listed [
read more
]
q3.
How much gas is used in your household?
Select one option:
Small house / flat (12,000 kWh)
Medium (18,000 kWh)
Large house (27,000 kWh)
Enter actual kWh used
Amount (kWh)
Calculate amount used from your bills
Select how your gas is measured:
Cubic metres (newer meters)
100's of cubic feet (older meters)
Latest meter reading
Reading 12 months before
Difference
kWh used
kWh
tonnes CO
2
Notes
:
Gas consumption is generally measured in units of volume, and this is converted on gas bills into units of energy i.e. kilowatt-hours (kWh) - see Sources page.
To make an accurate calculation of the CO
2
generated, you can enter the annual kWh used (if you know this), or you can calculate it from your bills.
To calculate from your bills, first select how your gas is measured. If your bills don't say what the units are, you can probably find the units on the meter. Recently installed meters measure gas in cubic metres (m
3
), but older meters measure in hundreds of cubic feet - or you may have the kWh already calculated.
Enter the meter reading at the end of the last quarter from the latest bill and then the reading from 12 months before.
The CO
2
factor for natural gas is 0.203 kg / kWh ...[
more
]
q4.
Is heating oil, coal, wood or bottled gas used in your household?
No
Yes
Enter your use over the last year:
The number of litres of
heating oil
:
The number of kilograms of
coal
:
The number of kilograms of
wood
:
The number of kilograms of
bottled gas
:
Then select 'Calculate'
tonnes CO
2
Notes
:
The following CO
2
factors are used.
For oil: 2.96 kg / litre
For coal: 3.26 kg / kg
For wood: 0.10 kg / kg
For bottled gas: 3.68 kg / kg
...[
more
]
q5.
How many cars are used by your household?
Select one option:
0
1
2
3
4
Car 1
Select car size:
Small car (37 mpg)
Medium car (33 mpg)
Large car (24 mpg)
Enter actual mpg:
Select 12-month car mileage:
Low (6,000 miles)
Average (9,000 miles)
High (12,000 miles)
Enter actual milage:
tonnes CO
2
Car 2
Select car size:
Small car (37 mpg)
Medium car (33 mpg)
Large car (24 mpg)
Enter actual mpg:
Select 12-month car mileage:
Low (6,000 miles)
Average (9,000 miles)
High (12,000 miles)
Enter actual milage:
tonnes CO
2
Car 3
Select car size:
Small car (37 mpg)
Medium car (33 mpg)
Large car (24 mpg)
Enter actual mpg:
Select 12-month car mileage:
Low (6,000 miles)
Average (9,000 miles)
High (12,000 miles)
Enter actual milage:
tonnes CO
2
Car 4
Select car size:
Small car (37 mpg)
Medium car (33 mpg)
Large car (24 mpg)
Enter actual mpg:
Select 12-month car mileage:
Low (6,000 miles)
Average (9,000 miles)
High (12,000 miles)
Enter actual milage:
tonnes CO
2
Notes
:
Select the size of car according to:
Small: < 1.5 litres
Medium: 1.5 - 2.0 litres
Large: > 2.0 litres
Or if you know the fuel consumption accurately, enter it in the appropriate box.
(You can obtain official fuel consumption figures from
vcacarfueldata.org.uk
. After entering Manufacturer, Model, etc, we suggest you select 'More Info...', and take the 'Imperial Combined' figure, but you then need to subtract 15% from the mpg to allow for 'real world' conditions)
To work out your annual mileage:
• If you have owned the car from new, divide the total mileage by the number of years
• For an older car, you can take the difference between the mileage shown on your last two MOT certificates.
Emissions are taken to be 14.3 kg CO
2
per gallon ...[
more
]
Section 2
(personal)
q6.
FOOD
How much of the food that you eat is organic?
None
Some
Most
All
tonnes CO
2
MEAT: How much meat/dairy do you eat personally?
Above-average meat/dairy
Average meat/dairy
Below-average meat/dairy
Lacto-vegetarian
Vegan
tonnes CO
2
FOOD MILES: How much of your food is produced locally?
Very little (much foreign / out of season food)
Average
Above average
Almost all
tonnes CO
2
FOOD PACKAGING AND PROCESSING: How much of your food is packaged / processed (e.g. 'ready meals', tins)?
Above average
Average
Below average
Very little
tonnes CO
2
COMPOSTING: How much do you compost potato peelings, leftover and unused food etc?
None
Some
All
tonnes CO
2
WASTE: How much food do you waste (on average, over one fifth of edible food is thrown away)?
Above average (50% more)
Average
Below average (50% less)
Very little (90% less)
FOOD TOTAL
including almost unavoidable 0.2 tonnes
tonnes CO
2
Notes
:
Non-farmed fish counts as organic.
The fertilizer used in growing food that is not organic causes greenhouse gas emissions through nitrous oxide released from the soil, and through CO
2
emissions from the manufacture and transport of fertilizer.
Meat and dairy production generates methane from animals and slurry, and CO
2
from the energy used in farm operations.
Food transport, packaging and processing all require energy, releasing CO
2
.
Food decomposition in landfill sites releases methane.
Edible food can be wasted because too much is prepared, or because it has gone past its use-by date and so on.
Some greenhouse gas emissions are currently almost impossible to avoid: methane from tilling and soil management, and CO
2
from arable farms and the operation of retail stores. These amount to around 0.2 tonnes per person.
...[
more
]
q7.
Health, education, etc :
tonnes CO
2
Notes
:
Carbon dioxide is generated by the health service, schools, social services, the armed forces and so on .
This amounts to 1.1 tonnes per person per year for the UK.
You have no direct control over this amount, which is generated on your behalf, but you can join campaigns to make public services more energy efficient, especially if you work within one of them.
q8.
Journeys by bus
Enter the number of miles travelled in the last year (or leave blank) and select 'Calculate':
Enter your regular mileage each week:
Enter your regular mileage each month:
Enter your other mileage in the year:
miles
tonnes CO
2
Notes
:
You can estimate your mileage by:
• estimate the average journey time
• multiply by average bus speeds
(roughly 15mph for urban journeys and 20mph for rural journeys).
If you are a regular bus traveller, enter a typical week and/or month and these will be multiplied up (by 48 and 12 respectively) and added to your other mileage.
The CO
2
emission factor for bus travel is taken to be 100 g/mile ...[
more
]
q9.
Journeys by train
Enter the number of miles travelled in the last year (or leave blank) and select 'Calculate':
Enter your regular mileage each week:
Enter your regular mileage each month:
Enter your other mileage in the year:
miles
tonnes CO
2
Notes
:
You can estimate your mileage by:
• list the train journeys
• add up the total journey time
(remembering to double if return)
• multiply by average train speeds
(roughly 20mph if suburban
45mph if cross-country
70mph if intercity ).
If you are a regular train traveller, enter a typical week and/or month and these will be multiplied up (by 48 and 12 respectively) and added to your other mileage.
The CO
2
emission factor for rail travel is taken to be 100 g/mile ...[
more
]
q10.
Flights:
Any flights from the UK to Europe and/or Africa?
No
Yes
Enter the number of
return
flights:
Ireland, N. France, Netherlands
Germany, Denmark
S. France, Switzerland, Italy, Norway
Spain, Croatia, Hungary, Poland
Malta, Sicily, Albania
Madeira, Canaries, Morocco, Bulgaria, Greece, Moscow
Azores, Cyprus, Egypt
Kenya
Zambia
Southern Africa, Mauritius
hours flying
Any flights from the UK to North & South America ?
No
Yes
Enter the number of
return
flights:
New York, Boston
Florida
The Caribbean, The Rockies, Western USA
Central America, Ecuador
Hawaii, Peru, Chile
hours flying
Any flights from the UK to Asia & Australasia ?
No
Yes
Enter the number of
return
flights:
Turkey
Jordan
Pakistan
India
Nepal, Bhutan
Sri Lanka, Thailand, China, Japan
Australia, New Zealand
hours flying
Any other flights e.g. between UK airports or between airports outside the UK?
No
Yes
Enter the number of hours spent flying:
total hours flying
tonnes CO
2
Notes
:
Enter the
number
of international return trips from the UK that you personally made in the last year.
Then the
hours
spent on flights within the UK, or in flights between airports outside the UK.
For example, if you went on one return trip with two friends to Spain, enter a "1" in the Spain box.
The calculator assumes emissions of ¼ tonne CO
2
equivalent per hour flying
(roughly 500 g per mile)...[
more
]
q11.
Miscellaneous personal lifestyle choices:
What is your miscellaneous spending?
Above-average (5 tonnes CO
2
)
Average (3.4 tonnes CO
2
)
Below-average (2.4 tonnes CO
2
)
Much below-average (1.4 tonnes CO
2
)
Do you recycle paper, glass and metal?
No
Yes
Do you recycle plastic apart from bags?
No
Yes
tonnes CO
2
Notes
:
Your miscellaneous spending is all your other spending i.e. on:
• recreation and leisure facilities
• housing
• household appliances
• hygiene
• hotels and other holidays
• furnishings
• clothing & footwear
• alcohol & tobacco
• post and telecommunications
• books, newspapers & magazines
and so on.
Almost all of this spending will be associated with greenhouse gas emissions to some degree. Spending on these tends to follow size of income.
Your total
tonnes CO
2
What to do now:
• Compare your total with the world and national averages in the chart below
• View/print a summary chart - click:
• Consider whether you want to set a target to reduce your total for the coming 12 months - we have found that a 10% reduction year on year is easily achievable.
Read more...
How your total compares to the rest of the world
Your total
World average
4
UK average*
13.4
USA
20
Sweden, Switzerland
6.1
China
3.2
India
1.2
Tanzania
0.1
Sustainable
1.5 ?
*The figure for the UK includes adjustments for greenhouse gases other than CO
2
and for imports - but the figures for the other countries do not, as these are not so readily available.
Notes
The calculator is based around a family household unit, where car travel is done to bring in income for the family or to travel for family leisure, and so CO
2
emissions need to be shared between all members of the household. If your circumstances are different, you may need to adapt the calculator, e.g. enter the household size as 1, and share out household electricity and gas before entering it.
Some travel may be carried out as part of your job e.g. international aid workers may have to fly in order to do their jobs effectively. Enter in the calculator just what you choose to do, not what you cannot avoid.
The 'sustainable' figure of 1.5 tonnes per year is uncertain - an amount that the world's oceans may be able to absorb. In this sense, it is sustainable - but stores of fossil fuels are finite, and so no emission level is sustainable in the very long term.
First published: Feb 2007
Last updated: 27 Jan 2019