Overview
An energy source is defined as secure if an electricity generator can be sure of obtaining enough of the fuel to maintain an adequate electricity supply.
Countries that rely on imported fuel to power their electricity supply expose themselves to energy security of supply issues - reducing dependence on constant imports of fuel to generate electricity can help to mitigate these.
This could include using renewable sources such as wind and marine, which do not depend on imported fuels, alongside fuels that come from a range of suppliers and can be stored.
The challenge in detail
The security challenge for each energy source
Fuels we have to import – such as coal and gas – bring with them security issues of price and supply. Renewable energy sources are not exposed to these issues, but are vulnerable to intermittency.
Hydro
As a native energy source hydro is highly secure, but the number of UK sites suitable for large-scale hydroelectric generation is limited, so it can only make a small contribution to our energy mix.
Marine
Marine energy could help improve the overall security of our energy mix by replacing imported fossil fuels. But wave and tidal technologies are subject to intermittency.
Solar
Solar energy is highly secure, but solar power is not available at night or in cloudy weather.
Wind
The UK is one of the windiest countries in Europe – but wind is intermittent so we need back-up generation that can be powered up at short notice.
Coal
The UK imported 79% of the coal used for electricity generation in 2009, most of it from one source. We are now diversifying our energy mix to be less reliant on coal.
Gas
By 2019, the UK will import 69% of the natural gas we use as our North Sea reserves dwindle. Importing from various countries and using diverse generating technologies will ease our vulnerability.
Nuclear
The UK imports all the uranium we use for nuclear fuel, but it can be sourced from several suppliers. Uranium is an energy-dense fuel and can be stockpiled against short-term insecurity of supply.
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Our energy approach
We want to bring affordable and low-carbon energy to all. With our experience, we can help the UK move toward a more sustainable energy future.
The energy mix
The UK is supplied by a variety of electricity generation sources, which we call the energy mix. Each energy source has its advantages and disadvantages.
Future energy
The UK’s electricity demand could exceed supply within the next decade, creating an energy gap. Find out how we plan to lead energy change to create a stable energy future.