It may surprise you to know that the gas we use around our homes every day is made up mainly of methane - the same chemical gas that's found in the gas expelled by humans on an almost daily basis! The gas supplied to our homes is actually called Natural Gas, and here we take a look at its properties.

We are told time and again that our natural gas reserves are finite, and that supply is running out. But where are these reserves, and why are they disappearing so quickly?

The trick to finding natural gas is to look out for other fossil fuels - like coal and oil. Wherever you find these resources, gas is sure to follow.

However, many of these reserves are now running dry, especially in the West, and as a result energy companies are increasingly turning to gas from less conventional sources in order to meet consumer demand.

Right now, you'll find most of our domestic gas comes from fields in the Middle East - the United Arab Emirates and Qatar, as well as Russia. But all this could change within a generation as their gas reserves dwindle and the world turns to other energy forms.

Natural gas is a very useful energy resource. It can be used in a variety of processes, form central heating to fuel for cars.

Some automobiles can be converted to run on natural gas, and compared to petrol, it is relatively clean burning and produces fewer toxic by-products. The use of gas as a car fuel is a relatively new technique which involves having your car's fuel system converted. But you'll find that gas is a much cleaner burning fuel option than the traditional diesel and petrol options.

However, the burning of natural gas still produces carbon dioxide as a by product, which is widely considered to be one of the greenhouse gases that is responsible for causing global warming. Although gas is considered one of the cleaner fuels, it's really the best of a bad bunch. Harmful carbon dioxide is produced on burning Natural gas, and this is bad news for the earth's environment and ozone layer.

The natural gas that is supplied to our homes is in fact far from natural. One of the initial processing steps is one which strips the Natural gas of any excess chemicals that are not needed, or may be dangerous. These chemicals include propane, nitrogen and ethane.

Once the gas has been purified, a small amount of foul-smelling but non-toxic perfume (if you can call it that) is added. The reason for this is that methane gas is completely transparent, with no smell of its own, and as such it is hard to detect in its pure form.

The addition of odour to domestic gas supplies was made standard practice after a tragedy that killed more than 300 people at a US college in the 1930's. At this time gas was still scent-free and a build up of the gas went unnoticed, until it was too late.