You may remember that we launched an appeal in December for volunteers for a new Breakfast experiment: to see how easy it is to go green.
Can our family shrink their carbon footprint?
We were looking for a typical family who were prepared to make some tough choices, to reduce their carbon footprint.
We were deluged with e-mails - many of you, it seems, are gluttons for punishment.
After sifting through hundreds of volunteers, we chose the Hawksworths.
They've got five children, two cars - and a stonking electricity bill.
Will teenager Lauren have to bin the fairy lights?
But can they change all that, with the help of Breakfast's team of experts and our presenter Declan Curry?
This morning on Breakfast, we met the Hawksworths for the first time - and found out just how tough the coming year is going to be for them.
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How to work out your carbon footprint
Your Carbon Footprint is effectively your own personal contribution to global warming.
It's the amount of extra carbon dioxide which you're responsible for producing each year.
Now, we all know that people produce only negligible amounts of carbon dioxide (each time we breathe out).
But, every time you get in your car, switch on your central heating or take a flight abroad, you're burning fuel - and that's what produces the CO2.
..or will 15 year old Alex have to unplug his Xbox?
You can get a general picture of your Carbon Footprint by going online, to websites such as Carbon Footprint or Climate Care (see links on the right hand side of this story).
You'll need to have your gas and electricity bills for the year to hand - and you'll need to be honest about your car mileage and the number of aircraft journeys you make each year.
But your own carbon footprint may be even bigger than their calculator suggests.
If, for instance, you have one of those very fashionable gas patio heaters, you'll be producing as much Carbon Dioxide in two hours as a car will create in a day.
The Hawksworth's personal footprint
Your Carbon Footprint will also be increased if you have a taste for out-of-season fruit and veg or fresh flowers in midwinter, flown in from Africa.
And, if you happen to have an old-fashioned open coal fire in your front room - the most inefficient form of heating - you'll need to take the amount of coal you use each year (in kg) double it and add it to your total carbon footprint.
Shrinking your footprint
An average British person has a carbon footprint of just under 11,000kg each year.
To halt global warming, scientists calculate that we need to reduce that - to around 2,500kg each year.
Over the next year, we'll be showing our guinea-pig family how they can go low-carb.
In the meantime, here are some small steps to get you started:
Change your electricity supplier - for one which specialises in renewable energy. You won't notice any change - but the environment will
Insulate your home properly, as heating accounts for 70% of our domestic energy use.
You don't have to splash out on double glazing. Use thick curtains at your windows and lay your own insulation in the loft.
If you can bear to turn down the thermostat by one degree, you'll save 300kg of CO2 each year.
Swap the car for a smaller model. A BMW X5 produces twice as much Carbon Dioxide as a Ford Ka.
Cut back on foreign air travel. It's not just the large amount of CO2 which planes produce which is a problem here, it's also the fact that they're so high in the earth's atmosphere.
If you want to calculate your exact carbon footprint, try the Collins Gem Carbon Counter (£4.99) ISBN: 978 0 00 724812
For advice on how to cut your own footprint, try the Energy Saving Trust helpline: 0800 512 012
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