Every year, each person in the UK is, on average, responsible for about 14 tonnes of greenhouse gas emissions. (The government's published figures suggest a lower amount, but they omit things such as international aviation.) So, if we want to make a genuine cut of 10% across the board, we need to reduce our emissions by about 1.4 tonnes each. Let's call it 1.5 tonnes, just to be sure.

To aid the process, I have broken the average citizen's lifestyle-related emissions into 10 distinct categories. Some emissions, of course, we can't do much about ourselves, as they arise from energy use outside our control. However, about two-thirds of that 14-tonne annual total comes from the way we run our homes, our personal transport and the things we buy.

To be clear: the figures I'm using are only averages. People lead very different lives; a person living in a small, city-centre flat without a car may have half the emissions of someone who flies every month and lives in a large, detached house. My suggestions for CO 2 savings are intended simply as a yardstick for where best to focus your attention (the annual projected savings are all calculated for an "average" energy consumer using the latest widely accepted figures). The choice of how to achieve a 10% cut in your emissions next year is down to you.

Domestic gas

(Responsible for just under two tonnes of CO 2 per person)

The amount of gas used at home is the most significant component of most people's carbon footprint. Gas use is largely driven by home heating, so it is the size of your house and how well insulated it is that determines how much energy you use. (Heating the hot water and running the cooker aren't anywhere near as important.)

In a year, the average home uses about 20,000 units (kilowatt hours) of energy via gas use. Your gas bills should give a figure for your usage each quarter – but remember you use very little in the summer months, so you'll need to add up the total across all four quarters. In our estimates, we've used the gas consumption habits of the typical UK home, lived in by the average 2.3 people, and assumed the house is on the mains gas network.

Annual savings in tonnes of CO 2

Major improvement in your home's insulation 0.4

New boiler if yours is more than 10 years old 0.3

Cavity wall insulation 0.3

Double glazing if you don't have it 0.2

Solar hot water 0.2

Increase loft insulation, seal doors

and skirting boards, etc 0.2

Better controls for boiler, hot water tank

and radiators 0.2

Buy a wood-burning stove 0.2

Reduce your thermostat temp by 1 degree 0.2

Heat one less room 0.1

Slow-flow showers, not baths 0.1

Electricity

(One tonne of CO 2 )

The average home uses about 4,000 units of electricity a year. Using this figure, and knowing that that there are an average of 2.3 people in each household, we can calculate that domestic electricity use accounts for about a tonne of CO 2 per person per year. The most significant users of domestic electricity are tumble dryers, fridges and large televisions, particularly plasma TVs.

The level of emissions produced in generating your electricity depends, of course, on the fuel used in the power station, which is why the government is encouraging the development of renewable power sources such as wind. In addition, recent changes to the subsidy scheme now make it more financially attractive to generate your own power from the sun or wind.

Annual savings in tonnes of CO 2

Install 2 kilowatt solar PV panels 0.4

Buy a new A++ refrigerator if yours is more than 4 years old, and only use a small-screen TV 0.1

Use LED or fluorescent lights where you currently have halogen lights installed 0.1

Buy an automated system to turn off appliances when not in use; get a meter that shows actual energy use and use it to monitor your household 0.1

Only use your washing machine and dishwasher

when full to capacity and at lowest temperature 0.1

Never use the tumble dryer 0.1

Get rid of the freezer if you can, and replace your small appliances with "eco" varieties 0.1

Car

(1.5 tonnes of CO 2 )

There is one car for every two people in the UK, and each one travels an average of about 9,000 miles a year. Old MOT certificates usually have a mileage figure on them, so you can use them to estimate the annual mileage of your household cars. Emissions are directly related to the amount of fuel you buy, and smaller, newer cars are about twice as energy-efficient as older, four-wheel drive vehicles.

For many city dwellers, a car-share scheme may be the best way of reducing emissions. Those who must have their own car can reduce their petrol bills by a surprising amount by taking a one-day eco-driving course that shows how our bad driving habits increase the amount of fuel we use.

Annual savings in tonnes of CO 2

Cut your annual mileage in half 0.7

Sell the second car 0.7

Buy a new car with emissions in car tax bands A or B, then scrap the old one 0.5

Join a car club or set up an effective local car-sharing scheme 0.4

Share car to work 0.3

Go on a day's eco-driving course, fit low-resistance tyres and check air pressure every month 0.2

Don't ever use a car for shopping. Buy online 0.1

Work from home one day a week rather than commuting by car 0.1

Air travel

(1.2 tonnes of CO 2 )

Almost half the people in the UK won't travel by air this year. Those who do fly take an average of about two trips a year. Nevertheless, this is an important source of emissions because of the long distances involved. One flight to Los Angeles and back is further than most people travel in their car during the entire year. I've also adjusted the figures to reflect the detrimental effect of aircraft emissions other than C0 2 , though there is still fierce scientific debate about the exact impact of these other pollutants.

Annual savings in tonnes of CO 2

Never fly 1.2

Restrict yourself to one short-haul return flight a year on a carrier with a fuel-efficient fleet 0.3

Consumer electronics

(0.5 tonnes of CO 2 )

The gadgets we love to buy are another major source of carbon emissions, albeit "hidden" because almost all our living-room appliances are made in the Far East. Our mobile phones, computers, games consoles and DVD players are packed with components from all over the world, often containing trace amounts of precious metals that have taken huge amounts of energy to refine. The best study on the footprint of home computers was carried out by Apple; it showed that a single new desktop machine created emissions of almost half a tonne during its manufacture. The simple rule is: buy less stuff, keep it longer and then ensure it is properly recycled; there are many organisations that will do this for you.

Annual savings in tonnes of CO 2

Buy secondhand mobile phones and ensure that three of your electronic devices are recycled 0.3

Keep your electronic devices (eg phones, TVs, computers, DVD players, games machines) one year longer than you would have 0.2

Switch from a desktop computer to a laptop at home, and recycle the desktop 0.1

Food

(1.5 tonnes of CO 2 )

This always surprises people, but the global food production system is a really important source of carbon dioxide and other greenhouse gases. Except for a few air-freighted foods, the main cause of the emissions isn't "food miles". Packaging is not particularly important either. The high emissions come from livestock farming and from the heavy use of fertilisers, some of which break down into nitrous oxide, a global warming gas hundreds of times more powerful than CO 2 . The best way to make a real difference to food-related emissions is to reduce your consumption of meat and dairy products. Veganism might not be popular, but it can make a big difference to CO 2 and methane emissions.

Annual savings in tonnes of CO 2

Go vegan three days a week 0.5

Change to an almost entirely vegetarian diet, using mostly unprocessed wholefoods such as grains, seeds and nuts 0.5

Never buy processed food or ready meals 0.2

Buy more carefully and never throw food away 0.2

Grow all your own fruit and vegetables for July, August, September 0.1

Clothing

(0.8 tonnes of CO 2 )

How can clothing be so important? The main reason, for people in the UK, is the use of wool and cotton fabrics that, when being produced, have very high greenhouse gas impacts. We buy 20kg or so of new clothes every year and each garment made from natural fibres has a typical greenhouse gas footprint more than 20 times its weight. Manmade fibres such as polyester are a better choice in terms of reducing emissions.

Annual savings in tonnes of CO 2

Buy 50% secondhand clothes 0.3

Reduce purchases by a more than a quarter compared to last year (eg buy four new T-shirts not the UK average of seven) 0.2

Buy only manmade fibres 0.2

Focus on new fabrics made from bamboo, hemp or other cotton substitutes 0.1

Water, sewage and waste disposal

(0.3 tonnes of CO 2 )

Pushing large volumes of water uphill to your house uses energy. After its use, the waste water then has to be treated, and some methane from the sewage escapes into the atmosphere. Some solid waste sent to landfill also generates emissions.

Annual savings in tonnes of CO 2

Install a 'grey water' recycling system to take water from your washing machine into your lavatory 0.1

Use showers, not baths. Install a flow-reducing aerator for the shower head 0.1

Regularly use soap, a basin of water and a sponge instead of a shower 0.1

Buy ultra-low water use cisterns, new water-saving dishwasher, washing machine. Recycle old ones 0.1

Install – and carefully monitor – a water meter. Put bricks in all the loos to reduce water. Carefully recycle all waste, compost all organic matter 0.1

Install a composting toilet 0.1

Public transport

(0.2 tonnes of CO 2 )

While we are all encouraged to use public transport more, the emissions aren't inconsequential. Faster types of ferry and high-speed trains (particularly diesel) can be worse than cars. But long-distance coaches are very energy efficient indeed.

Annual savings in tonnes of CO 2

Cycle everywhere 0.3

Always use coaches instead of the train 0.1

Work from home two days a week instead of taking public transport to work 0.1

Paper

(0.3 tonnes of CO 2 )

Taking a tree and breaking it up into tiny fibres, turning it into a slurry that is then pressed into sheets of paper is incredibly energy intensive. Newspapers such as the Guardian are now made from nearly 100% recycled newsprint, thereby avoiding much of this energy use, but the embedded energy use should be considered. However, magazines made from virgin paper have far higher footprints. It also doesn't help that Britons are said to be among the largest consumers of toilet paper in the world.

Annual savings in tonnes of CO 2

Only buy newspapers, magazines, books, toilet paper and copier paper made from recycled materials 0.1

Block direct mail, choose electronic bills and statements, buy secondhand books and share papers 0.1

'I'm a frequent flyer. I haven't got a chance in hell of pulling this off'

Yes, flying a lot does drive up your carbon footprint considerably. More than anything else, flying habits cause the largest fluctuations in people's lifestyle-related emissions. While almost half the population doesn't fly at all in any typical 12-month period, some people take up to 20 flights a year. This table shows how emissions can vary enormously depending on the distance flown:

Two return trips on holiday to the Med 2.4 tonnes

Ski flight to Geneva 0.5 tonnes

Business conference in New York 2.7 tonnes

Quarterly meetings in Frankfurt 1.4 tonnes

Sales trips to Hong Kong and Sydney 14.3 tonnes

Source: Latest Defra estimates, adjusted to reflect current seat occupancy levels (75% according to IATA, August 2009) and using a multiplier of 2 to reflect the non-CO2 impacts of aircraft in flight)

Anyone taking all these flights over a year might rack up a carbon footprint totalling more than 35 tonnes. For such a person, the 10% reduction could conceivably come from making savings in other areas, but probably they'll only get there by cutting one or two flights. It isn't too difficult.

Option 1 Take holidays by car or rail. Southern France can be easily reached in a day from London. Paris to Aix-en-Provence is three hours by TGV and about £50.

Option 2 Cut one of the quarterly Frankfurt meetings and take the Eurostar ski-train to the Alps.

Option 3 Participate in that New York conference by video link.

Option 4 Merge the two sales trips to the Far East and Australia into one itinerary.

Perhaps you think you can't cut your flying. But about five million flights from Heathrow last year were to internal meetings with people in the same organisation. Perhaps some of these would have been excellent candidates for replacing with video conferencing?

'I've never knowingly done anything green in my life. Where do I start?'



You're going to find this easy. It will only take a few simple changes to take a substantial slice off your carbon footprint. Just cutting out the obvious wastes of energy will almost certainly reduce it by 10% without any significant change in your lifestyle. The savings in cash may be noticeable as well. Here are some easy suggestions . . .

• Adjust the central heating controls so that the boiler is only on when you need it. Large numbers of households still don't use their central heating controls properly. Set the timer correctly, make sure the temperature sensitive valves on the radiators are in the correct position, and use the thermostat to control temperatures (a lot of people use it simply as an on/off switch).

• Reduce electricity bills by turning off appliances at the wall when they are not in use, rather than leaving them on standby. This won't save a huge amount of electricity, but it helps.

• Put energy-efficient bulbs in all your lampshades. This alone might save 10% of your electricity bill.

• Never drive on journeys of less than a mile or so. Almost 30% of journeys are less than two miles. Would a bike be better, more convenient and more fun?

• Almost everybody recycles newspaper now. But what about composting food waste, sorting the plastics and giving the clothes to the charity shop? All these things will make a small difference individually, but taken together they might shave a few percent off your total carbon footprint.

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