4.1 Energy Sources & Non-renewables
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Wind turbine.
There are many ways that we can generate electricity. We generate electricity from renewable and non-renewable energy resources.
Renewable energy resources will never run out; we will always have access to these. Examples of renewable energy are:
The main advantages of renewables are that they will not run out. However, the energy that they provide tends to be unreliable, especially solar, tidal, wind and waves as some time there can be a lot of energy (due to it being a very windy day) and other times they can be no energy (due to a day only having a slight breeze). Most of the renewable energy resources do damage the environment but the damage is considerably less than non-renewable energy sources. We will go through many of the renewable power sources and we will see the effects that they have on the environment.
Non-renewable energy sources are finite, meaning that they will eventually run out. We currently generate most of our energy from non-renewable energy sources. Examples of non-renewable energy sources are:
Non-renewables cause considerable amount of damage to the environment both through the extraction/ mining of them and when they are used to generate electricity. We will go through each of the energy sources to see the effects that they have on the environment. Oil, coal and natural gas are known as fossil fuels.
Renewable energy resources will never run out; we will always have access to these. Examples of renewable energy are:
- Solar
- Wind
- Waves
- Tide
- Geothermal
- Hydroelectric
- Biofuel
- Food
The main advantages of renewables are that they will not run out. However, the energy that they provide tends to be unreliable, especially solar, tidal, wind and waves as some time there can be a lot of energy (due to it being a very windy day) and other times they can be no energy (due to a day only having a slight breeze). Most of the renewable energy resources do damage the environment but the damage is considerably less than non-renewable energy sources. We will go through many of the renewable power sources and we will see the effects that they have on the environment.
Non-renewable energy sources are finite, meaning that they will eventually run out. We currently generate most of our energy from non-renewable energy sources. Examples of non-renewable energy sources are:
- Oil
- Coal
- Natural gas
- Nuclear fuels
Non-renewables cause considerable amount of damage to the environment both through the extraction/ mining of them and when they are used to generate electricity. We will go through each of the energy sources to see the effects that they have on the environment. Oil, coal and natural gas are known as fossil fuels.
Fossil Fuels
Fossil fuels (and nuclear fuels) are the world’s main source of energy. In the UK about three quarters of our energy is generated from fossil fuels. Fossil fuels store energy in the form of chemical energy. When they are burnt, they transfer chemical energy into heat, which heats water or air (depending on what the power station). The steam/ hot air turns a turbine. The energy is being transferred from heat to kinetic. The turbine is then connected to a generator, which turn kinetic energy into electrical energy.
Fossil fuels (and nuclear fuels) are the world’s main source of energy. In the UK about three quarters of our energy is generated from fossil fuels. Fossil fuels store energy in the form of chemical energy. When they are burnt, they transfer chemical energy into heat, which heats water or air (depending on what the power station). The steam/ hot air turns a turbine. The energy is being transferred from heat to kinetic. The turbine is then connected to a generator, which turn kinetic energy into electrical energy.
What a power station looks like.
Most power stations run on coal or natural gas.
There are many advantages and disadvantages to using non-renewables as a form of energy. One advantage is that fossil fuels are relatively cheap and they are easy to obtain. However, this may not always be the case as we start to run out of fossil fuels, meaning there are less being obtained and the ones that are being extracted may become more expensive to extract. Also, a rising population will likely increase the demand for fossil fuels and this would be met with a price increase. Another positive is that fossil fuel power stations can be turned on and start producing electricity very quickly. This means that they can easily respond to changes in electricity demand. Natural gas has the quickest turn on time.
A disadvantage of fossil fuels is that they are finite and eventually they will run out. Also, the burning of them can release harmful chemicals into the environment that have adverse effects. The burning of coal and oil releases sulphur dioxide, which can lead to breathing problems and acid rain. Fossil fuels also release carbon dioxide, which causes global warming because of the enhanced greenhouse effect. Out of the three fossil fuels, coal produces the most carbon dioxide relative to the amount of energy produced. Many scientists and economists are calling for coal to be kept in the ground and never burnt. One way to reduce the amount of carbon dioxide that goes into the atmosphere is to capture it. This process is known as carbon capture. When the carbon has been captured it can then be stored underground, in an old oil or gas field. Carbon capturing technologies are rapidly evolving over time.
There are many advantages and disadvantages to using non-renewables as a form of energy. One advantage is that fossil fuels are relatively cheap and they are easy to obtain. However, this may not always be the case as we start to run out of fossil fuels, meaning there are less being obtained and the ones that are being extracted may become more expensive to extract. Also, a rising population will likely increase the demand for fossil fuels and this would be met with a price increase. Another positive is that fossil fuel power stations can be turned on and start producing electricity very quickly. This means that they can easily respond to changes in electricity demand. Natural gas has the quickest turn on time.
A disadvantage of fossil fuels is that they are finite and eventually they will run out. Also, the burning of them can release harmful chemicals into the environment that have adverse effects. The burning of coal and oil releases sulphur dioxide, which can lead to breathing problems and acid rain. Fossil fuels also release carbon dioxide, which causes global warming because of the enhanced greenhouse effect. Out of the three fossil fuels, coal produces the most carbon dioxide relative to the amount of energy produced. Many scientists and economists are calling for coal to be kept in the ground and never burnt. One way to reduce the amount of carbon dioxide that goes into the atmosphere is to capture it. This process is known as carbon capture. When the carbon has been captured it can then be stored underground, in an old oil or gas field. Carbon capturing technologies are rapidly evolving over time.
A nuclear power station.
Nuclear Power
The main nuclear fuels are uranium and plutonium. They are non-renewable because there is only a finite amount of them in the world and when they run out, they run out. The nuclear fuel undergoes a controlled chain reaction, which produces heat. The heat then turns water into steam, which then drives a turbines that is connected to a generator, which creates electricity.
Nuclear fuel is a million times more effective than coal. Also, no carbon dioxide is produced, meaning that there is no enhanced greenhouse effect from using nuclear fuel (and no need for carbon capturing technologies).
A negative is that there is a possibility that there could be an accident and radioactive material could be leaked into the environment, which would have an adverse effect on health and the natural landscape. Nuclear reactors are very safe but there is a slim possibility of this happening. After the 2011 tsunami and earthquake in Japan, the Fukushima nuclear power plant had a meltdown and radioactive waste was released into the environment. Another disadvantage is that it takes the longest time out of all of the power stations to power up, meaning that it is less responsive to changes in electricity demand. Nuclear power stations are very expensive and time consuming to build and decommission.
The main nuclear fuels are uranium and plutonium. They are non-renewable because there is only a finite amount of them in the world and when they run out, they run out. The nuclear fuel undergoes a controlled chain reaction, which produces heat. The heat then turns water into steam, which then drives a turbines that is connected to a generator, which creates electricity.
Nuclear fuel is a million times more effective than coal. Also, no carbon dioxide is produced, meaning that there is no enhanced greenhouse effect from using nuclear fuel (and no need for carbon capturing technologies).
A negative is that there is a possibility that there could be an accident and radioactive material could be leaked into the environment, which would have an adverse effect on health and the natural landscape. Nuclear reactors are very safe but there is a slim possibility of this happening. After the 2011 tsunami and earthquake in Japan, the Fukushima nuclear power plant had a meltdown and radioactive waste was released into the environment. Another disadvantage is that it takes the longest time out of all of the power stations to power up, meaning that it is less responsive to changes in electricity demand. Nuclear power stations are very expensive and time consuming to build and decommission.
Responding to Energy Demand
Power stations take different amounts of time to turn on depending on what fuel they are being powered from. The list below shows which fuel type is the fastest:
Coal and nuclear tend to be kept on constantly to provide a ‘base load’ electricity as they have the longest start up time. The base load on a grid is the minimum level of demand on an electrical grid over 24 hours. Oil and gas powered power stations are used to provide extra electricity at peak times because they have the shortest start time.
Power stations take different amounts of time to turn on depending on what fuel they are being powered from. The list below shows which fuel type is the fastest:
- Gas
- Oil
- Coal
- Nuclear (uranium and plutonium)
Coal and nuclear tend to be kept on constantly to provide a ‘base load’ electricity as they have the longest start up time. The base load on a grid is the minimum level of demand on an electrical grid over 24 hours. Oil and gas powered power stations are used to provide extra electricity at peak times because they have the shortest start time.