The majority of the world’s electrical energy comes from nonrenewable sources, such as the burning of coal, oil, and gas, or from nuclear power stations. As the link between global warming and amount of carbon dioxide in the atmosphere becomes clearer, the need to find additional, renewable sources becomes more urgent. The following activities will introduce students to types of energy resources, and help them decide when and where each type is appropriate to use!
Essential Questions for Energy Resources
- What is the best way to produce electricity?
- Why do we need to change how we generate electricity?
- How is generating electricity linked to global warming?
Background Information on Energy Sources
The first town in the world to have a public electricity supply was Godalming, England. In 1881, a company installed a generator connected to a waterwheel. They laid cables in the gutters and connected them to streetlights. Since this time, the global consumption of electricity has rapidly grown.
Fossil fuels are created from the remains of living things and they take millions of years to form. The world's reserves of fossil fuels are running low, as they are being used at a much faster rate than they are being created. Although burning fossil fuels is a cheap and reliable source of generating an electric current, the carbon dioxide it produces is having a negative effect on the environment. For more information about the effects of greenhouse gases on the environment check out the lesson plans on the greenhouse effect and global warming.
Fossil fuel power stations burn fossil fuels to heat water. This water then turns into high-pressured steam. The steam runs over a turbine, making the turbine spin. The spinning turbine is connected to a generator and the generator produces an electric current. Examples of fossil fuels include coal, oil and gas.
- Fossil fuels are cheap to mine and to convert into electrical energy.
- Burning fossil fuels has been reliable.
- Fossil fuels can be burned safely.
- Fossil fuels greatly contribute to global warming, as burning fossil fuels releases carbon dioxide into the atmosphere.
- Coal also contains impurities such as sulfur that, when burned, can form sulfur dioxide. Sulfur dioxide in the atmosphere can lead to acid rain.
- Supplies of fossil fuels will run out one day.
Energy is released from the nuclei of atoms using a nuclear reaction. This reaction is known as fission and involves splitting large nuclei, such as in a uranium atom, into smaller nuclei, releasing vast amounts of energy. This energy is used to heat water and turn it into steam. This steam then drives a turbine, which turns a generator and produces an electric current.
- Power stations are generally safe.
- Nothing is burned, so no greenhouse gases or atmospheric pollution are emitted.
- A small amount of fuel can produce a large amount of electrical energy.
- The waste from nuclear power stations remains radioactive and harmful to living things for thousands of years, so it needs to be disposed of carefully.
- Nuclear power stations are safe, but if something goes wrong like a major natural disaster or a terrorist attack, they have the potential to be very dangerous.
- Nuclear power stations have very high setup costs
Harnessing wind energy involves putting turbines in places where there is a lot of wind. The movement of air causes the blades to spin, which in turn can drive a generator to produce an electric current. Wind turbines can be used individually or together in groups as wind farms. As well as using them on land, they can also be used offshore.
- Turbines do not burn anything and do not emit any other atmospheric pollution.
- There are no fuel costs because the "fuel" is moving air around a turbine.
- Wind turbines are not expensive to run once set up.
- Some people argue that the turbines can ruin an area’s natural beauty.
- Setup costs can be high, particularly for multiple turbines.
- The effectiveness depends on the amount of wind, so they are not always reliable.
- Turbines can be noisy.
Solar energy works using photo-voltaic cells to harness light energy from the sun and convert it into electrical energy.
- Solar energy has no atmospheric pollution because nothing is burned.
- Solar panels can be used in remote locations or even made to be portable.
- There are no fuel costs associated with solar energy.
- Solar power systems can be expensive to set up
- Solar power is not always reliable because the effectiveness depends on how much sunlight an area receives.
Tides are the movement of water caused by the gravitational pull of the moon. Barrages (dam or barrier) are built across the mouth of rivers, estuaries, and in bays. These barrages contain turbines which spin when the water moves. These turbines drive generators which can produce an electric current.
- Tidal energy does not involve burning fuel, so there are no fuel costs or greenhouse gases.
- Tides are predictable; high and low tides occur in well understood cycles.
- Barrages have long life spans.
- Tidal energy has very expensive setup costs.
- Building barrages can harm marine habitats.
- Barrages can block access to certain rivers or other waterways.
Waves are caused by wind and result in water moving up and down. This kinetic energy can be harnessed and transferred into electrical energy. There are many different ways of doing this.
- Wave energy is renewable and will never run out.
- There are no harmful emissions associated with wave energy.
- Wave energy is not suitable for all locations. Most inland areas cannot use wave energy.
- Wave energy stations can have a negative effect on marine life.
- Wave energy stations can destroy the natural beauty of coastal areas.
Geothermal power uses thermal energy found underneath the ground. Cold water is pumped down underground and is converted into steam. This steam is then passed through tubes to a turbine which spins as the steam passes over it. The spinning turbine drives a generator and produces an electric current.
- Geothermal energy is reliable.
- There are no greenhouse gases emitted from the station because nothing is burned.
- There are no fuel costs because geothermal energy uses the natural heat of the earth.
- Could potentially release underground greenhouse gases.
- There are high setup costs associated with geothermal energy.
- Geothermal energy can only be used where there is volcanic activity.
Biomass is material that comes from living things, like plants and animals. Biomass, such as wood, can be burned and used to heat water into steam. The steam is used to make a turbine spin. This turbine is connected to a generator which generates electricity.
- Biomass energy is renewable: as we burn the biomass we grow more plants to replenish the stock.
- Biomass energy is reliable.
- The carbon dioxide released by burning the biomass is absorbed by regrowing plants.
- Land used for livestock or growing food may have to be used instead for growing energy crops.
- Biomass energy requires large amounts of water.
With hydroelectricity, water is kept behind a dam in a high place. This water has gravitational potential energy and is converted into kinetic energy as the water falls. This moving water makes a turbine spin. The turbine is connected to a generator which produces an electric current.
- With hydroelectricity, there is no burning or atmospheric pollution.
- Water is a renewable resource.
- Dams are very expensive to build.
- Large areas of land need to be flooded for the reservoirs.
- Dams can stop migrating fish.
Additional Energy Resources Activity Ideas
- Make a poster PSA explaining why renewable energy resources are better than nonrenewable energy resources.
- Use a T-Chart to compare two different energy resources.
- Have students make a timeline describing the main stages of the development of energy engineering.