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Personal Carbon Footprint Spreadsheet

Are you - Then our spreadsheet might help. It helps you do an audit and find out where your emissions are piling up, which should give you an idea of where to try and make changes. You might find it quite enlightening, too.

Our Spreadsheet

The spreadsheet is a simple tool to help you measure the greenhouse gases generated to create and deliver all the resources you personally consume.  The "Intro" tab explains the details of using it.  The annual emissions figure you calculate will almost certainly be greater than the result provided by other carbon calculators due to the inclusion of food, consumer goods, government activities etc.

To put your number into context, you may like to compare it to the current global average per capita carbon emissions (around 6T), the 'safe' level of per capita emissions calculated by the IPCC (around 1.2T), and this set of consumption footprints calculated for 2001.  It is probably not helpful to compare it with the per-capita average emissions for your country unless your country has very few imports and exports.  The common values published for a country's emissions are for emissions produced within a particular country, not those emitted to produce the goods and services used there.

Without further ado, please download our spreadsheet:

(This spreadsheet is licenced under a Creative Commons Licence.) Creative Commons License

Help make it better

This spreadsheet is the result of only one couple's efforts!  There are many gaps in our data, and many of the emissions factors we have included are quite specific to the area in which we live.  Please contact us with any suggestions for improvements or to submit new emissions factors for inclusions in later versions of this spreadsheet.

The spreadsheet is current available for Microsoft Excel and Open Office.  We would be very happy if you took it to another level like putting a similarly detailed but friendly front-end onto a database like AMEE.

We have made this spreadsheet available under a creative commons license.  Feel free to share it, to improve on it and to include it in projects of your own.  We ask only that you 'share alike' and that you credit our work back to us.  If you wish to use it on other terms or think that we have misused your copyright then drop us a line.

We hope that you find this a useful tool to help you make informed choices about your carbon emissions.

Background - Why we made the spreadsheet

Our Thinking

We believe that carbon emissions must be addressed at the consumption end.  Production and provision of goods and services is driven by the consumer, so we think they also bear responsibility for any associated emissions. Sadly, the consumer cannot see how their choices impact on their emissions.

Most online carbon calculators measure your direct energy use:  the fuel you burn in your car, your utilities, and how much you fly.  Some include waste disposal, but we have not found any that include in detail the emissions associated with your food and other consumables, nor any that account for what the government does "on our behalf".  (Our favourite was Carbon Neutral. The worst said that we had no emissions at all, since we didn't own a car!)

Ideally, we wouldn't need these calculators anyhow—the information they provide would be embedded in our grocery bills. The planet's limited capacity to cope with greenhouse gases would be factored into prices alongside the limited supply of suitable land, water, skilled humans, and other resources required to produce the good or service.  Until we get a carbon price, and are confident that it is high enough to reflect the underlying environmental costs, concerned consumers will continue to seek out carbon calculators to guide their choices.

Heather and I needed a more detailed guide than we could find. We had already made many simple changes, and wanted to know which further efforts would be most valuable.  We also wanted to know how much we were living 'beyond our means'.  Inspired by the author of the now defunct blog Green With a Gun, we decided that a thorough audit of the carbon emitted to support every aspect of our lives was possible.

Our Audit

For three months, from March to May 2008, almost everything coming into or leaving the house was measured.  Martin weighed all the groceries, rubbish bags, and recycling.  Heather calculated distances driven by friends running errands for us, or travelled by purchases shipped to us and gifts we mailed away.  Luckily, the city council bills us for sewage volume and we were happy to use their estimate.

Heather also compiled tables listing the emissions associated with the production and disposal of the various goods we were recording, as well as services like transport and government.  Then we built a spreadsheet to apply her factors to our daily measurements and to split out our share of inputs to the wider household.

You can see here how our own emissions have changed over the time we have been using the spreadsheet, and here you can see a breakdown of the sources of our emissions along with a variety of other environmental footprints subsequently developed from the same ledger data. (If you are interested in calculating these other footprints for yourselves please contact us.)