Gas is a fossil fuel which can be used to generate electricity. By burning gas, we create heat which powers a turbine. The rotation of this turbine spins a generator which creates electricity.  

How do gas power stations work? 

There are three types of gas power stations: 

  1. OCGT - Open cycle fast turbines, these are generally smaller and use gas, which when burnt produces hot air that drives the turbine and produces electricity. There are hundreds of these across the country. OCGTs are cheap to build and good for short runs in producing energy. 

  2. CCGT - combined cycle gas turbines, these are primarily the same as OCGTs at the beginning, except the hot air that exits the engine is then used to heat water, this creates steam which drives another turbine producing more energy, making them much more efficient but are more costly to build. 

  3. CHP - combined heat and power, these again are like OCGTs at the beginning. However, the heat from the engine is then used for other purposes, such as local district heating or larger stations using the steam to power chemical services such as oil refineries. CHPs are efficient but only when the heat can be used effectively.  

The future of gas 

Gas is a fossil fuel, meaning that we find it in pockets under the earth’s surface. It is a finite, non-renewable source of energy. The process of burning gas creates greenhouse gases which contribute to global warming. As part of GB’s ambition to reach net zero by 2050, we need to step away from using gas power.  

However, gas power remains an important part of today’s generation mix to make sure we have a secure supply of electricity across Great Britain. Gas power stations help us to manage the unpredictability of renewable energy sources by creating inertia - something which is vital as we integrate more renewables onto the system.  

Gas power stations in Great Britain 

There are over 30 gas power stations in Great Britain but the power that we require from them has reduced over recent years as renewable energy becomes more readily available. 

However, with coal power plants in Britain set to close by 2025, we’ll look to gas power stations in the short term to provide the inertia we need on our system.  

The ESO is currently running pathfinder projects to find new ways of procuring inertia that don’t rely on fossil fuels so we can become an even greener system operator.