3.4 - Energy Sources in the UK
The types of energy sources in the UK
Energy is essential for powering machinery, providing heat, and generating light. In the UK, energy comes from a variety of sources, broadly classified into two categories based on their sustainability and environmental impact.
Renewable energy sources
Renewable energy is derived from resources that are naturally replenished over a short timescale and do not deplete. Examples include solar power from the Sun, wind, hydroelectric power from water, and tidal energy. These sources are generally less polluting.
Non-renewable energy sources
Non-renewable energy is obtained from resources that will eventually run out or become too costly to extract, either economically or environmentally. This includes fossil fuels like coal, natural gas, and oil, which were formed from ancient organic matter over millions of years, as well as nuclear energy, which relies on uranium, a finite resource.
Renewable energy sources and their importance
Renewable energy sources are sustainable as they can be used repeatedly without depletion. Most of these sources produce minimal pollution, with the exception of biomass, which can emit greenhouse gases during combustion. They play a growing role in the UK's energy strategy, contributing to environmental goals and energy security.
Main types of renewable energy in the UK
| Renewable source | How it generates energy | Significance in the UK |
|---|---|---|
| Biomass | Energy derived from organic materials, such as burning animal waste or plant matter, and producing biofuels from crops like wheat and barley. | Contributes to about 3% of road transport fuel and over 5% of electricity generation through biofuels and waste. |
| Wind | Wind turns turbines, located on land or offshore, to produce electricity. The UK benefits from being one of the windiest regions in Europe. | Accounted for nearly 20% of electricity generation in recent years, with significant potential for future expansion despite public opposition. |
| Hydroelectric Power (HEP) | Water stored in large dams or smaller micro-dams flows to spin turbines, generating electricity. | Supplies around 2% of electricity, with micro-dams gaining popularity at local levels due to lower cost and controversy compared to large dams. |
| Geothermal | Underground water heated by hot rocks produces steam to drive turbines for electricity generation. | Limited use in the UK, with small-scale projects in areas like Southampton's city centre, but potential for niche applications. |
| Tidal | Turbines in barrages across estuaries harness the movement of tides to generate power. | Currently no operational tidal barrages due to high costs and environmental concerns, but could potentially supply up to 10% of electricity with future developments in areas like Swansea Bay and Bridgwater Bay. |
| Wave | Waves push air through chambers to turn turbines connected to generators. | Experimental projects exist in the UK, though high costs and environmental issues limit widespread adoption compared to pioneers like Portugal. |
| Solar | Photovoltaic cells in solar panels convert sunlight into electricity. | Contributes about 4% of electricity, with growing numbers of solar farms and residential installations, particularly effective during summer months. |
Non-renewable energy sources and their role
Non-renewable energy sources are critical to the UK's current energy supply but are finite and often associated with significant environmental pollution, particularly through greenhouse gas emissions. The main types in the UK include fossil fuels and nuclear power.
Key non-renewable energy sources in the UK
- Coal - Once the dominant energy source, coal's use has drastically declined. A century ago, millions worked in deep mines, but today, only a few thousand work in the industry. The last deep mine shut in 2015. Coal is now only extracted from opencast pits.
- Natural gas - A major source, providing nearly half of the UK's electricity. Historically sourced from the North Sea, now increasingly imported, with about 44% from the North Sea, 47% from Europe, and the remainder as liquefied natural gas from further afield.
- Nuclear - Relies on uranium, a non-renewable resource, to generate power. It accounts for about 21% of the UK's electricity through 15 reactors, chosen for access to cooling water and proximity to ports for uranium imports. Future plans include new reactors at sites like Hinkley Point in Somerset and Sizewell in Suffolk, expected to be operational in the early 2030s, replacing older facilities.
The energy mix in the UK and its composition
The energy mix refers to the combination of different energy sources used in a region. The UK benefits from a diverse energy mix, balancing renewable and non-renewable sources to meet demand while addressing environmental concerns.
Composition of the UK's energy mix
| Energy source | Percentage of total energy |
|---|---|
| Petroleum | 38% |
| Natural gas | 38% |
| Renewables and nuclear | 17% |
| Coal | 6% |
| Other | 1% |
This distribution shows that fossil fuels, particularly petroleum and natural gas, dominate the UK's energy supply, making up 76% of the total. The decline of coal reflects a shift towards cleaner alternatives, while renewables and nuclear power are increasingly significant, supporting efforts to reduce carbon emissions.