Renewable Energy Sources

Solar Power

Solar cells generate electricity directly from sunlight. Solar panels use sunlight to heat up water in order to make energy. 

Advantages of solar power:

• After being made, solar cells and solar panels create zero pollution. 
• In countries that get a lot of sun, solar power is a reliable source of energy. 

Disadvantages of solar power:

• A lot of energy is required to build solar panels and solar cells. 
• Solar power can only be generated during the day. 
• Solar power is less reliable in countries like the UK where we get less sun (but still fairly reliable). 
• Electricity production cannot be increased if energy demand suddenly goes up. 

Wind Power

Wind turbines rotate when the wind blows towards them in order to generate electricity. 

Advantages of wind turbines:

• After being built, wind turbines produce zero pollution. 
• They cause no permanent damage to the environment.

Disadvantages of wind turbines:

• Wind turbines are not as reliable as non-renewable energy sources because if there is no wind or the wind is too strong, they cannot generate electricity. 
• Electricity production cannot be increased if energy demand suddenly goes up.
• Some people think that wind-turbines are an eyesore. 

Geothermal Power

Underground hot rocks can be used to either generate electricity or heat buildings. 

Advantages of geothermal power:

• Geothermal power is very reliable because the rocks are always hot.
• Geothermal power stations only have a small environmental impact. 

Disadvantages of geothermal power:

• Geothermal power stations can only be built in certain locations where the rocks are hot due to volcanic activity.

Hydroelectric Power

Hydroelectric power is often made using a hydroelectric dam. The gravitational potential energy lost by water falling from the top to the bottom of the dam is converted into kinetic energy which is used to turn turbines. 

Advantages of hydroelectric power:

• After the dam is built there is no pollution.
• Hydroelectric power is reliable in countries that get a lot of rain. 
• If demand suddenly increases, the dam can increase energy production straight away. 

Disadvantages of hydroelectric power:

• To build a dam a valley must be flooded. This destroys the habitats of many plants and animals. 

Wave Power

Waves turn turbines which are placed along coastlines. 

Advantages of wave power:

• After turbines are built they produce no pollution.

Disadvantages of wave power:

• Wave power is unreliable because it depends on the wind. 
• Turbines may disturb animals and destroy many habitats. 

Biofuels

Biofuels are made from plants and animal waste and are burned in the same way as fossil fuels to create electricity. 

Advantages of biofuels:

• Plants grown to produce biofuels absorb carbon dioxide from the atmosphere whilst they are growing. 
• Crops can be grown all year long. 
• Extra biofuels can be stored for times when energy demand increases and so they are reliable.

Disadvantages of biofuels:

• Carbon dioxide is released into the atmosphere when biofuels are burned. This is a greenhouse gas and contributes towards global warming. 
• Areas of forests have been cleared to grow biofuels which has destroyed many habitats. 

Limitations of Renewable Energy Sources

We know that renewable energy resources are better for the environment than non-renewable energy resources, but currently there are not enough sources of renewable energy built to stop using non-renewables entirely. The cost of building new powerplants and switching energy sources will be high. Governments do not want to raise taxes to pay for this because it may make them unpopular. Also, many people do not want to live near a powerplant such as a hydroelectric dam or a wind farm.