Renewable energy
In 2018, around a third of the UK's electricity was generated by renewable energyPower that is generated using natural resources that will not run out, eg wind and wave power. sources. They are a non-finite resourceA renewable energy that harnesses the Earth's natural resources. as they harness the Earth鈥檚 natural resourcesResources found on the planet that have been produced without human involvement.. Examples include:
- wind
- solar
- tidal
- hydroelectric
- biomass
Wind
Wind energy is harnessed through the use of wind turbines - tall towers with three propeller blades (vanes) that appear frequently around the UK.
The blades turn with the wind, driving a generatorDevice that converts kinetic energy into electrical energy., which produces the electricity. While there are many dotted around the countryside as single towers or in a small group, they are now more commonly grouped together off-shore in large quantities to form a wind farm.
Advantages of wind | Disadvantages of wind |
Wind energy is constantly available and sustainable | When there are periods of low wind, little or no energy is produced |
There is no cost for wind and the running cost of a wind turbine is relatively low | They cost a lot to build and put in place |
Some people do not like the look of wind turbines or feel that they spoil the natural landscape |
Advantages of wind | Wind energy is constantly available and sustainable |
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Disadvantages of wind | When there are periods of low wind, little or no energy is produced |
Advantages of wind | There is no cost for wind and the running cost of a wind turbine is relatively low |
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Disadvantages of wind | They cost a lot to build and put in place |
Advantages of wind | |
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Disadvantages of wind | Some people do not like the look of wind turbines or feel that they spoil the natural landscape |
Solar
Solar panels are made from photovoltaicConverting light energy into electrical current. cells, which harness the Sun鈥檚 light energy and convert it into electricity. Solar power provides clean energyClean energy does not produce as many pollutants to the environment as other sources. from a plentiful supply, but there is still considerable development work to be done to try to make solar panels more efficient. The placement of the solar panels is also very important to ensure they track the path of the sun and harness the optimum amount of solar energy.
Advantages of solar | Disadvantages of solar |
Clean, renewable energy source | Some people do not like the look of solar panels or feel that they spoil the appearance of a building |
Reduces household energy bills | Costs a lot to install |
Does not produce much electricity when there is considerable cloud cover, during the winter months or at night |
Advantages of solar | Clean, renewable energy source |
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Disadvantages of solar | Some people do not like the look of solar panels or feel that they spoil the appearance of a building |
Advantages of solar | Reduces household energy bills |
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Disadvantages of solar | Costs a lot to install |
Advantages of solar | |
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Disadvantages of solar | Does not produce much electricity when there is considerable cloud cover, during the winter months or at night |
Tidal
The UK currently only generates a small amount of energy from tidal power, but it is estimated that the UK could potentially harness around a fifth of its electricity demand in this way. Tidal energy relies on the gravitational pull of the Moon, which causes the change in water levels known as tides.
A tidal barragesA dam that is used to generate energy from moving water in and out of a bay or river due to tidal forces. is built across the mouth of a river where it meets the ocean. The barrage is constructed so that the incoming tide passes through turbineRevolving machine with blades that are turned by wind, water or steam. Turbines in a power station turn the generators. to generate electricity. It also harnesses the reverse flow of the water when the tide goes out.
Advantages of tidal | Disadvantages of tidal |
Clean, renewable energy source | Construction of tidal barrages is expensive |
Tidal power plants will last for a long time | Environmental impact of tidal barrages is unknown |
Could produce a fifth of the UK鈥檚 needs as it is an island surrounded by the sea |
Advantages of tidal | Clean, renewable energy source |
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Disadvantages of tidal | Construction of tidal barrages is expensive |
Advantages of tidal | Tidal power plants will last for a long time |
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Disadvantages of tidal | Environmental impact of tidal barrages is unknown |
Advantages of tidal | Could produce a fifth of the UK鈥檚 needs as it is an island surrounded by the sea |
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Disadvantages of tidal |
Hydroelectricity
Hydroelectric schemes use a damA structure built to slow down or stop the flow of a river. This creates a large lake or reservoir, which can be used for water supply, leisure or electricity generation. to block a valley or a major river, often creating a reservoirA place where water is stored. behind the dam.
Once the water has built up behind the dam, it is directed and released by valve A device that allows movement in one direction. through turbines. The turbines turn generators to produce electricity.
Advantages of hydroelectricity | Disadvantages of hydroelectricity |
Clean, renewable energy source | Construction of dams is expensive |
Valves can be opened very quickly to produce energy at peak times | Objections from people in the surrounding environment |
No pollution when running it | Affects the wildlife by flooding the valley |
Advantages of hydroelectricity | Clean, renewable energy source |
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Disadvantages of hydroelectricity | Construction of dams is expensive |
Advantages of hydroelectricity | Valves can be opened very quickly to produce energy at peak times |
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Disadvantages of hydroelectricity | Objections from people in the surrounding environment |
Advantages of hydroelectricity | No pollution when running it |
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Disadvantages of hydroelectricity | Affects the wildlife by flooding the valley |
Biomass
biomassThe dry mass of an organism. energy involves growing plants or using animal materials, not for consumption but so that they can be burned to produce heat. Plants such as rapeseed or willow are specifically grown as biomass crops so that they can be burned in a furnace.
Advantages of biomass | Disadvantages of biomass |
Clean, renewable energy source | Creates atmospheric pollution when burned |
Carbon dioxide is released in the process and can be reused by plants | Land used for energy crops may be needed for other purposes such as agriculture |
Replacement plants can be grown very quickly to ensure a good supply |
Advantages of biomass | Clean, renewable energy source |
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Disadvantages of biomass | Creates atmospheric pollution when burned |
Advantages of biomass | Carbon dioxide is released in the process and can be reused by plants |
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Disadvantages of biomass | Land used for energy crops may be needed for other purposes such as agriculture |
Advantages of biomass | Replacement plants can be grown very quickly to ensure a good supply |
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Disadvantages of biomass |
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