Natural gas: a clean energy source with many uses

A clean energy source

As its name indicates, natural gas is not highly processed after extraction; at the start it is colourless and odourless. It is “odorised”, though, for safety.

Burning natural gas produces little apart from water vapour and carbon dioxide: it gives off no smoke, no particles.

Natural gas generates half as much nitrogen oxide as coal or heating oil to produce the same amount of energy, and nearly 30% less carbon dioxide.

By comparison with other non-renewable sources of energy, natural gas gives off the least CO₂ (55kg per gigaJoule of heat, against 75kg for crude oil and nearly 100kg for coal). Likewise, any condensing boiler using natural gas will give off half the CO₂ of newly-installed direct electric heating.

Natural gas is often used nowadays in low-energy buildings to supplement renewable energy sources.

An energy source with many applications

Natural gas has two main advantages. First, it’s the most energy-efficient of all fossil fuels in the market. Second, it’s an energy source that needs no storage facilities on the consumer’s premises.

The home and office market
Natural gas is mostly used as a heat source for cooking or space heating. 38% of Europe’s natural gas consumption is used by the home and office sectors, mainly for heating.
Natural gas appliances are becoming more and more efficient, as many solutions (like condensing boilers and heat pumps) make for savings in older as well as new-built premises.

The industrial sector
Industry uses 34% of the natural gas consumed in Europe. Gas is not greatly used as a raw material (only 4%) but its industrial applications – in chemicals, petrochemicals and refining – account for 25% of its use.

For instance, natural gas is used to synthesize ammonia and urea in manufacturing agricultural fertiliser.

Electricity generation
The power generating sector has been contributing to the rise in natural gas use world-wide over the last ten years, and now accounts for 20% of consumption. This rising trend is expected to continue due to heavy demand from the emerging countries; by 2020 the forecast is that 35% of the gas sold each year will be used to generate electricity.

The use of natural gas in electricity production cuts CO₂ emissions, especially when compared with coal-fired power stations. The capital spending and running costs for a gas-fired power station are much lower as well, often boosting financial profitability by 50%.

Motor vehicles: Natural Gas Vehicles (NGV)
Natural gas is also used nowadays as a fuel for motor vehicles: the same natural gas as we use for heating or domestic cooking, but compressed for better storage.
This gas is compressed to 200 bar, a similar pressure to that in an undersea diver’s compressed air bottles. The gas needs no processing apart from compression, so it’s still a clean energy source giving off far less CO₂ than petrol or diesel fuel.

There are already over one million natural gas vehicles world-wide. France had more than 1,400 buses in 2009 (nearly 15% of the bus fleet), 500 household waste trucks, 30 HGVs and thousands of light vehicles fuelled by compressed natural gas.