What is natural gas?
Natural gas is a fossil fuel and thus is a finite resource. It is formed when the prehistoric remains of animals and plants are buried and subjected to high temperatures and pressures for millions of years. It comprises mostly methane. Nearly half of the electricity generated in the UK currently comes from gas-fired power stations, in which gas is burned to generate steam, which is used to drive a turbine connected to an electrical generator.
Gas-fired power stations can provide a flexible, reliable electrical output, but are fuelled increasingly by imported gas as the UK's North Sea reserves decline. The price of gas, and therefore of electricity produced using it, is volatile and can rise and fall sharply in response to international events outside the UK's control.
Burning gas also emits greenhouse gases. Carbon capture and storage (CCS) technology could present a possible solution, though it has not yet been proven to work on an industrial scale. CCS is also expected to increase the cost of constructing a gas-fired power station, and reduce its efficiency. In a recent report the Climate Change Committee, which advises the Government on carbon emissions, predicts that gas-fired power stations both with and without CCS will remain part of the UK's electricity generating mix for the foreseeable future.
How electricity is generated through gas
See how electricity is generated at a gas-fired power station.
Is it plentiful?
Gas reserves will last until the 2070s at the current rate of consumption, but this rate is likely to increase. Gas is an important fuel for UK electricity generation, and greater efficiency and a diverse mix of generating technologies should help to stretch gas resources further.
Is it secure?
The UK imported 45% of the natural gas it used in 2009 and, as North Sea reserves dwindle, this is predicted to rise to 69% by 2019. But the UK imports from a variety of countries and a diverse mix of generating technologies can help to mitigate this.
Is it predictable?
UK gas-fired power stations have an assumed availability at peak of 90%. Gas plays a significant role in making the UK's overall electricity supply reliable.
Is it affordable?
By 2020 the cost of generating electricity using natural gas should be about 8p/kWh, or about 11p/kWh with carbon capture and storage technology to reduce emissions.
Is it clean?
Gas-fired power stations have a carbon footprint of 487gCO2e/kWh. Using carbon capture and storage (CCS) technology, that could be brought down to about 170gCO2e/kWh. Gas will likely play a role in UK generation for many years, but the long-term future for gas-fired power stations is with CCS.
EDF Energy's approach
Gas is an important part of EDF Energy's mix.