National and global energy resources

• The main ways in which we use the earth’s energy resources are for generation electricity, heating and transport. Most of our energy currently comes from fossil fuels - coal, oil and natural gas
• Reliable energy resources are ones that are available all the time or at predictable times and in sufficient quantities. Some energy sources are more reliable than others
• Non renewable energy resources are not replaced as quickly as they are used and will eventually run out. For example, fossil fuels and nuclear fission.
• Renewable energy resources can be replaced at the same rate they are used and will not run out. For example, solar, tidal, wave, wind, geothermal, biofuel and hydroelectric energies
• Coal is a non renewable energy source mainly used for generating electricity. It is extracted from underground and there is enough available to meet current energy demands, it is reliable so supply can be controlled and meet demand, and it is relatively cheap to extract and use. However, it will eventually run out, releases carbon dioxide when burned (causes climate change) and releases other polluting gases such as sulfur dioxide which causes acid rain
• Oil is a non renewable energy source extracted from underground that is mainly used for generating electricity, transport and heating. There is enough to meet current energy demands, it is reliable so supply can be controlled to meet demand and is relatively cheap to extract and use. However, it will eventually run out, releases carbon dioxide (climate change), releases other polluting gases like sulfur dioxide which causes acid rain and oil spills can kill marine life
• Natural gas is a non renewable energy source extracted from underground and is mainly used for generating electricity and heating. There is enough available to meet current energy demands, it is reliable so supply can be controlled to meet demand and is relatively cheap to extract and use. However, it will eventually run out and releases carbon dioxide when burned (climate change)
• Nuclear fission is sourced from mining naturally occurring elements, such as uranium and plutonium and is mainly used for generating electricity. There are no polluting gases or greenhouse gases produced, there is enough available to meet current energy demands, large amounts of energy transferred from a very small mass of fuel and is reliable so supply can be controlled to meet demand. However, it produces nuclear waste, which is dangerous, difficult and expensive to dispose of and stored for centuries before it is safe to dispose of. Nuclear power plants are also expensive to build and run and to decommission (shut down)
• Solar energy is sourced from sunlight transfers of energy to solar cells and to solar heating panels. Its main uses are for generating electricity and heating. It can be used in remote places, is very cheap to run once installed and releases no greenhouse gases or pollution. However, supply depends on the weather, its expensive to buy and install and cannot supply large scale demand
• Hydroelectric energy is a renewable energy source from water flowing downhill turning generators. Its main uses are for generating electricity and it has low running costs, no fuel costs and is reliable, so supply can be controlled and meet demand. However, it is expensive to build hydroelectric dans, and large areas behind the dam must be flooded, destroying habitats and resulting in large greenhouse ga production from rotting vegetation
• Tidal energy is a renewable energy source generated by turbines on tidal barrages turned by water as the tide comes in and out. Its main uses are for generating electricity and it has a predictable supply as there are always tides, can produce large amounts of electricity, has no fuel costs and releases no greenhouse gases or pollution. However, tidal barrages change aquatic habitats and can harm animals, restrict access and can be dangerous for boats and are expensive to build and maintain. You also cannot control the supply and supply varies depending on the time of the month
• Wave energy is a renewable energy source generated by floated generators powered by waves moving up and down. It is mainly used for generating electricity and has low running costs, no fuel costs and produces no greenhouse gases or pollution. However, floating generators change aquatic habitats and can harm animals, restrict access and can be dangerous for boats and are expensive to build, install and maintain. It is also dependant on the weather and cannot supply large scale demand
• Wind energy is a renewable energy source generated by turbines turning in the wind. It is mainly used for generating electricity and heating and is sourced by radioactive substances deep within the earth transferring heat energy to the surface. It has low running costs, no fuel costs and produces no greenhouse gases or pollution. However, supply depends on weather, large amounts of land needed to generate enough electricity on a large scale demand and can produce noise pollution for nearby residents
• Biofuels are a renewable energy source produced by fuel sources from living or recently living organisms, for example plants and animal waste. It is mainly used for generating electricity and transport and can be carbon neutral - the amount of carbon dioxide released when the fuel is burnt is equal to the amount of carbon dioxide absorbed when the fuel is grown. It is relatable and supply can be controlled to meet demand, but it is expensive to produce biofuels, growing biofuels requires a lot of land and water that could be used for food production and it can lead to deforestation as land is cleared for growing biofuels requires crops
• Geothermal energy is a renewable energy source from radioactive substances deep within the earth that transfer heat energy to the surface. It is mainly used for generating electricity and heating and it has low running costs, no fuel costs and produces no greenhouse gases or pollution. However, it is expensive to set up and is only possible in a few suitable locations around the world