Natural Gas and the Environment

It is now recognised that natural gas can play a significant role in reducing energy related pollution. It is the cleanest burning of all fossil fuels, producing the lowest level of pollutants.

The single biggest contributor to the greenhouse effect world-wide is carbon dioxide. Natural gas produces less carbon dioxide than any other energy form derived from fossil fuels (including thermal electricity). No carbon dioxide is emitted during the end use of electricity, but a disproportionate amount is released where electricity is generated from fossil fuels.

Carbon monoxide although not a greenhouse gas in a direct way still contributes to the greenhouse effect interfering with the chemical reactions in the atmosphere. Since natural gas produces little carbon dioxide its carbon monoxide – methane effect is negligible.

Acid Rain (which kills trees, soils and lakes) is caused by burning fuels with high sulphur content; natural gas is free of sulphur and makes negligible contribution to the problem.

Methane, the main constituent of natural gas does contribute CO2 to the greenhouse effect. It is therefore, important that methane emissions should be minimised (losses caused during transport and distribution).

However, although the absorptive capacity of a methane molecule (CH4) is 26-32 times larger than that of a CO2 molecule, the lifetime of a CH4 molecule is far shorter than that of a CO2 molecule. Consequently, the ultimate contribution made by a methane molecule to the greenhouse effect is not 26 – 32 times but only 5-10 times larger than that of a CO2 molecule. Of the 540 million tons of CH4 emissions a year only 10% is attributable to gas transport, the biggest sources are to be found in nature itself; marshes, rice paddies and intestinal gases from cows and termites.

There are estimated to be almost twice the natural gas reserves to oil reserves in the world.