The news is constantly full of talk about 'carbon footprints' - but
do you actually know how big yours is? Find out whether you're a
green angel or a carbon criminal with Mark Lynas's step-by-step guide
Mark Lynas
Wednesday January 24, 2007
Guardian
Now that the size of Tony Blair's carbon footprint has finally been
established (clue: it's big), we can all feel good about ourselves at
last. We can't all be that bad, surely? We haven't been invited to
Bee Gee Mansion in Florida recently, nor have we hung out with Cliff
in Barbados too many times over the past year. But then, there was
the weekend break in Barcelona ... and a year's worth of school runs
... not to mention the heating bills for the second home in the
Cotswolds ... oh dear.
Today is carbon judgment day: it is time to find out just where you
lie on the carbon emissions scale. No ifs, no buts, no excuses. With
the government mulling over possible national carbon rationing
schemes, we will all need to get more carbon-literate over the coming
years. Are you a low-emitting green angel, or the new Jeremy
Clarkson? George Bush, or George Monbiot? It's time to find out the
truth.
First, you need to assemble the evidence. A pen and a piece of paper
would be handy too. Let's start with your house. Dig out a year's
worth of gas bills if you use gas for central heating and cooking.
We'll also need a year of electricity bills and any other fossil
fuels you use domestically, such as oil for your boiler or coal for
your Aga (God forbid!). The second area to look at is transport. If
you own a car, we need the mileage and model to make an emissions
estimate. If you don't write down distances driven (and who does?),
find your two most recent MoT certificates - they'll give you the
overall mileage driven in the year, and you can base an estimate on
that. Then think back to your holidays, and any regular commutes you
do, to get the gist of your year's worth of travel.
1. Gas and heating
Heating is the biggest user of energy in domestic households,
accounting for 70% of the energy we use, so reducing it is the best
way to get your total down. Yes, we know all about wearing extra
jumpers and turning the thermostat down by a degree, but if you
actually want to feel comfortable in your home, the three things to
think about are insulation, insulation, insulation. If you're in a
post-Victorian home, make sure your cavity walls have been done. All
lofts should also be insulated to a minimum depth of 30cm, and any
more fibreglass you can stuff up there will make your house warmer
still. If you are a pensioner or on benefits, you can get grants for
this from the government. All this will help you burn less gas.
So let's start with your gas bills. They'll generally be quarterly,
and we need the figures for kilowatt-hours (kWh) from the bill,
rather than units from the meter.
To give you an idea of how profligate or thrifty you are, here are
some bog-standard averages, for the average house inhabited by Mr and
Mrs J Public in Privet Drive, Godalming, Surrey.
Small house: 10,000kWh per year.
Medium house: 20,500kWh per year.
Mansion: 28,000kWh per year.
To convert your kWh into carbon emissions, multiply the total by
0.19, and for your personal total, divide by the number of adults in
the house.
Write down your carbon footprint from gas
"But I don't use gas for heating," I hear you object. Don't worry.
If you've got an oil-burning boiler, find out the number of litres
you use in a year and multiply this figure by 2.975.
Oil is more carbon-intensive than gas, so people using oil for space
and water heating will probably have a higher carbon footprint than
those using gas in their houses. But the worst possible option is to
use coal: coal is nearly pure carbon, and when you burn it, you get
nearly pure carbon dioxide. (Gas, on the other hand, because it has
hydrogen atoms in its molecules, produces a lot of water - H2O - when
burned.) So take the total weight of coal burned in kilograms and
simply double it to get the carbon dioxide emissions.
Write down your carbon footprint from heating oil and your carbon
footprint from coal
But what if you burn wood? Well, the emissions impact of this is
questionable. There is a degree of local pollution from wood smoke to
worry about (it smells nice, but many of the particles in wood smoke
are highly carcinogenic), but in terms of greenhouse gases, any
effect is countered by the regrowing of the trees that were cut down
for the logs in your fire. So unless your logs came from a tropical
forest clear-cut and which won't be replanted, you can count wood as
zero carbon impact. Hooray!
2. Electricity
The other big use of power in the home is, of course, electricity.
Domestic electricity use just keeps on rising, largely because of our
insatiable appetite for more electronic gadgets. Between 1972 and
2002, electricity use in the household sector doubled, and is
projected to rise another 12% by 2010. You don't have a cappuccino
maker? Pah! Get with it.
Then there is the standby issue: televisions and digital set-top
boxes may never be switched off at the wall (though they should be);
hi-fi equipment keeps on humming away long after the Abba Gold CD has
played out; phone chargers left plugged in by the kids continue
soaking up power too - touch them and you'll see they feel warm. That
warmth is electricity, going to waste.
So, we need your electricity bills - like gas bills, these are
usually issued quarterly. If you can't find them, your supplier
should still be able to give you a useage figure over the phone (if
you can ever get through to the call centre, of course). Figures
should be in kilowatt-hours again, please.
And here are Mr and Mrs J Public's national averages.
Small house: 1,650kWh per year
Medium house: 3,300kWh per year
Bee Gee Mansion: 5,000kWh per year
To convert this figure into carbon emissions, multiply by 0.43. Don't
forget to divide this by the number of adults in the house to get
your personal figure. (Now you can see how living alone hugely
increases someone's ecological footprint, while house- sharing can
halve it at a stroke.)
Write down your carbon footprint from electricity
What if you're on a green tariff? This is another grey area. Most
green tariffs offered by the big electrical suppliers simply charge
you a premium - often matched by the company - which goes into a fund
to support renewables projects. This is good, but it doesn't make you
carbon-neutral. A greener option by far is offered by the smaller
company Good Energy, which pledges to match your electricity use with
100% renewable power. If you're signed up with them, you can put a
zero in the box above. Another good option is Ecotricity, which
spends more per customer than any other company on new renewable
investments.
3. Transport
Cars are the bete noire of all environmentalists, and for good
reason. Car culture, as well as being unhealthy and ecologically
destructive, is self-perpetuating. Before cars were in widespread
use, shops or amenities tended to be within walking or cycling
distance, within a tightly defined community. Now, with suburban
sprawl and the rise of out-of-town shopping, people may have to drive
miles to get a pint of milk or a loaf of bread. The average shopping
trip in Britain is 4.3 miles - hardly a walkable distance. And the
supermarkets tell us it's all about convenience. Hmm.
Road transport accounts for fully a fifth of the UK's entire national
carbon emissions, totalling 33m tonnes in 2004. Road traffic in the
UK is on an unrelenting upward trend, and has increased by 10% since
Labour came to power in 1997. Because politicians are terrified of
being labelled "anti-car" by the motoring lobby, little has been done
to persuade people to use public transport or travel less often.
Indeed, the economics stack up against it: the real cost of motoring
fell by 9% between 1997 and 2005, while bus fares increased by 15%
and rail fares by 5%. The government now spends £1bn a year on
expanding the road network, despite knowing that this will increase
traffic further. And yes, this money could have built an awful lot of
wind turbines and solar panels, and insulated a lot of people's
houses. Shame, that.
Now let's calculate your car's carbon emissions. Apart from your
mileage, the most important factor here is the type of car you drive.
If it's a Jag or a Humvee, then your total's going to be pretty high.
To get your total, we need to multiply your mileage by the car's
emissions per mile - you can't be expected to know this offhand, so
the best thing to do is to find your car model and type on the online
database at vcacarfueldata.org.uk. This will give you a figure for
emissions in grams per kilometre. Write it down.
Now multiply this figure by the number of kilometres you drove over
the year. (If you're starting with miles, multiply this by 1.609 to
get, er, "kilometreage".) Then divide by 1,000 to get the total in
kilograms. (Again, make sure this is your personal total - so halve
it for journeys made when you shared the car with another adult, for
example.)
Write down your carbon footprint from driving
Of course, public transport also has a carbon cost attached to it.
We're accustomed to thinking of trains as "good", but many people
don't know that a small car with three people in it is more efficient
per passenger mile than most trains. Trains also generally cover
greater distances, so you probably can't afford to skip this part of
your carbon budget, tedious as it may be to try and calculate. (Doing
your tax return will be a breeze after this!) One time-saving option
might be to decide on an average week and multiply it by 52. Regular
commuting journeys are easier to tot up, and for occasional bigger
journeys you can find the distances between different towns in the UK
by using the AA online route planner at theaa.com. Don't give up -
we're nearly finished.
Again, we need kilometres, so multiply mileage figures by 1.609. When
you've finished, add up all your carbon cost figures to find out your
total.
Kilometres travelled by train
Multiply by 0.11 for carbon cost
Kilometres travelled by bus
Multiply by 0.09 for carbon cost
Kilometres travelled by underground
Multiply by 0.09 for carbon cost
Kilometres travelled by ferry
Multiply by 0.47 for carbon cost
Write down your carbon footprint from public transport
There. That's done. But wait - haven't we forgotten one very large
and increasingly controversial area of emissions? Ah yes: flights.
Britain's CO2 emissions from aircraft doubled in the space of a
decade between 1990 and 2000, and are projected by the government to
double again by 2030. (This is a prophecy that ministers seem
determined to make self-fulfilling with their policy to hugely expand
airport capacity throughout the country, encouraging still more
people to fly.) Aviation's impact on the climate is worsened by fact
that jet emissions happen high up in the atmosphere, where they can
do most damage. The greenhouse impact of carbon dioxide is also
augmented by warming from water vapour in contrails too, as well as
other gases emitted by aircraft. In total, the Intergovernmental
Panel on Climate Change estimates that direct CO2 emissions from
aircraft need to be mulitplied by a factor of 2.7 to account for the
full warming effect of flights.
The reason that flying is so controversial among environmentally
aware people is that a single long-haul return flight - say, from
London to Sydney - will, by itself, double most people's carbon
footprint for the entire year. It's not that aircraft are uniquely
bad - indeed, the per-mile emissions are comparable to driving a car
the same distance - but that the distances involved are so huge. It
is because flights allow us to travel so many thousands of miles in
just a few hours that their carbon cost is so high. Having said that,
don't imagine that short-haul flights are a good way to get around
either, because proportionally more fuel is used in take-off and
landing, so short-haul flights are really the worst of all possible
transport options.
If you're reasonably map-literate, the best way to calculate your
carbon emissions for any flights you have taken is to visit the
website chooseclimate.org/flying. It lets you click your departure
point and destination, and does all the calculations for you, with
the aviation-emissions multiplier included. Alternatively, if your
geography isn't up to finding Lima or Milan on a map of the world,
there are plenty of other easy-to-use carbon calculators on the web:
carboncalculator.org from the carbon offsets company Climate Care is
probably the best, though it will give a slightly lower total for the
same flight than Choose Flying, because less of a multiplier is
factored in.
Now take a deep breath, and enter your carbon emissions (in
kilograms) from flights in the past year.
Write down your carbon footprint from flights
4. Consumption
We've done household emissions and we've done transport. But add
these two together and they comprise only two-thirds of the UK's
national emissions. The missing third comes from the industrial
sector: manufacturing, retail and services. Every item you buy, from
strawberries to CDs, has an energy penalty associated with it: the
energy in gathering the raw materials, in processing and
manufacturing, transporting and then selling it to you. (Not to
mention all those advertising execs sitting in their heated offices
in Soho doodling and figuring out how to sell you all this stuff you
didn't know you needed in the first place.)
You won't find this energy penalty quantified on the label, so even
if you wanted to you wouldn't be able to go rifling through all your
cupboards adding together the damage for each can of baked beans or
pair of knickers. So here we really do have to make an informed
guess.
Calculations by George Marshall, carbon lifestyle specialist at the
Climate Outreach and Information Network, give us the following
shorthand guesstimates:
· I have the latest of everything, love shopping and eat mostly
packaged convenience food: add 3,000kg.
· I'm fairly thrifty, but buy new things when I need them and get
most of my food from supermarkets: add 2,000kg.
· I mostly grow my own organic food, shop locally, reuse and recyle,
and wouldn't touch out-of-season green beans with a bargepole: add
600kg.
So it's your call. If you lie somewhere in between on this scale,
feel free to estimate your own figure. (If only the Inland Revenue
was so forgiving.)
Write down your carbon footprint from consumption
5. The bottom line
It's now (drum roll) time for the moment of truth. Go back over these
pages and add all the figures together. This should give you a grand
total, in kilograms, of carbon emitted during a year. This is your
personal carbon footprint.
Now, write down your total carbon footprint
So, how did you do? If we add together what a "sustainable" carbon
budget might be for the whole world, and then divide it by the global
population, we get a figure of about one tonne (1,000kg) per person.
Unless you live in a fossil fuel-eschewing eco-village in Somerset,
there's every chance you'll be over this total at present and living
a climatically unsustainable life. In fact, the national average for
the UK is 9,400kg, about 10 times what would be sustainable for the
planet. Still, we're not the worst, by any means: the average US
carbon footprint is 19,800kg, while the impact on climate of the
average Aussie is 18,000kg. Developing countries are far more
sustainable: the average Chinese carbon footprint is 3,200kg, while
the average Indian emits 1,200kg. Indeed, a good rule of thumb is
that the poorer a person is, the less they emit - not a good omen in
a world where everybody wants to be middle class. The average
Tanzanian is highly sustainable, with a mere 100kg of carbon
emissions per year, but it is unlikely that they are happy with this
situation.
No lifestyle assessment would be complete without a spurious grading
system, so here's one for your carbon footprint.
How you compare
A 1,000-3,000kg Either you're very green indeed, or you're lying.
Hopefully it's the former.
B 3,000-6,000kg You're nearly there. Only a couple of tonnes to go.
C 6,000-9,000kg You're getting close to the national average. Could
do better.
D 9,000-12,000kg You're an overconsumer. Sort it out now!
E 12,000-15,000kg You're a carbon criminal. Shouldn't you be reading
the Daily Mail?
F 15,000-18,000kg You're Tony Blair (he came in at 17.9 tonnes). Do
send our love to Cliff and Robin.
G 18,000-21,000kg You live like an American.
H 21,000+ You're Jeremy Clarkson. Shoot yourself now. For the planet.
· This article is based on Mark Lynas's book Carbon Counter,
published by Collins and priced at £4.99. Got a question on your
carbon footprint? Put your query to Mark Lynas here and you could win
a copy of Carbon Counter.
