What is Carbon Footprint?

A person’s carbon footprint is the total set of greenhouse gases like carbon dioxide, methane etc emitted by him and his activities. Similarly carbon footprints can be calculated for a product, an event or an organization. The carbon footprint depends on three factors

The nature of greenhouse gas released - carbon dioxide is the most commonly maligned green house gas but it is not the only one. Methane emitted by cattle is a much more potent green house gas. To solve the problem caused by the different green house potential of different gases they are converted to their respective carbon dioxide equivalents.

The amount of gas released and -

The place where the green house gas is released - Thus airplanes that release green house gases at a high altitude are considered to have a carbon footprint that is 1.9 times larger than if the same quantum of these gases had been released at sea level.

The carbon footprint is now calculated by using a cradle to grave approach i.e., it is a holistic calculation involving production, transport, usage and disposal for a product for example.

Why carbon foot prints?

Thinking about carbon footprints is a simple way of thinking about ways and means of reducing environmental pollution. By reducing ones carbon footprint each one of us can contribute to making the earth a safer, better place to live in.

Of more immediate concern to skeptics may be the global negotiations in Copenhagen aimed at reducing greenhouse gas emissions in industrialized countries. It is likely that the billions of dollars that will be needed to enforce these cuts may have a debilitating effect on the economy or cause many more manufacturing jobs to migrate to less developed nations. It therefore makes sense to invest in technologies that would reduce the carbon footprint allowing developed countries to continue to grow without a commensurate increase in green house gas emissions.

Reducing the Carbon footprint – Follow the three R’s.

There are many ways in which the carbon footprint may be reduced – by eating less of animal products, flying less often, driving fewer miles in a fuel efficient vehicle and preferable in a car pool, buying fewer clothes, installing energy efficient equipment and many others. Remember the three R’s – “Reduce, Reuse and Recycle”.

Carbon footprint and electricity

Estimates suggest that almost half of our carbon footprint is due to electricity and 17 % is due to lighting alone. We depend on electricity to meet several of our daily requirements. Electricity in turn can be produced by coal, gas, or nuclear plants or by renewable sources like geothermal, hydroelectricity solar and wind. The carbon footprint of a household or person is directly correlated with the amount of electricity consumed and the source of the electricity. The table below shows the grams of CO2equivalent produced when 1 KWH of electricity is produced from different sources.

Source	Grams of CO2 produced for every 1 KW generated
Coal	955
Oil	893
Natural Gas	650
Nuclear Energy	60
Hydro Electricity	15
Solar Energy	40

Most of the electricity is produced by fossil fuel burning plants and once the losses in transmission and distribution are accounted for it is estimated that for each KWH of electricity that a house hold consumes releases 830 grams of carbon dioxide equivalents in the air.

Save electricity – reduce carbon emissions

Since close to 830 grams of carbon equivalents are released in the consumption of 1 KWH of electricity it follows that this carbon emission can be reduced if electricity consumption is reduced. Replacing an old refrigerator, installing movement sensors, unplugging instruments when not in use are some of the methods one may employ depending on the availability of time and monetary resources. However there is one investment in energy saving instruments that is certain to generate a handsome return.

Replacing Incandescent bulbs with LED lighting

LED lamps and tubes not only consume a fraction of the energy consumed by incandescent bulbs, they have the double benefit of lasting almost forever and containing no mercury.

	Incandescent	LED
Power Consumption (watts)	50	6
Kwh (Units of Electricity Used Each Hour)	0.05	0.006
Hours of Operation Per Day	10	10
Carbon Emissions (tons) per year/lamp	0.152083	0.01825
Reduction in Carbon Footprint (tons) / lamp		0.133833
Lighting Carbon Emission (tons) per year/house	6.84375	0.82125
Reduction in Carbon Footprint (tons)		6.0225

By doing nothing except installing LED's in the house it is possible to reduce one’s carbon footprint by a whopping 6 tons per year. To put it in perspective this saving of 6 tons is equivalent to reducing gasoline consumption by 700 gallons! And if you were to offset this carbon footprint you would have to shell out close to $ 2 per year. The added benefit is that LED lights give at least 10 years of hassle free service. Some people criticize LED lighting for being expensive but a cost benefit analysis will show that LED lamps deliver a minimum of 6% annual return in running costs alone.