Presentation on theme: "Wind Energy – energy from the wind"— Presentation transcript:
1 Wind Energy – energy from the wind Geothermal Energy – energy from the EarthDeep underground, the Earth’s rocks are naturally very hot. We can turn their heat energy into electrical energy to use in our homes – we call this ‘geothermal energy’.Cold water is pumped below the ground.Hot rocks heat the water, turning it into steam.The steam is used to generate electricity.Wind Energy – energy from the windUsing wind turbines, we can turn the kinetic energy of the wind into electrical energy which we can use in our homes. This is ‘wind energy’.
2 RenewableNo pollution, because nothing gets burnedDoesn’t damage the environmentVery few places in the world where you can do thisCosts a lot of money to drill deep into the groundRenewableNo pollution, because nothing gets burnedNeed lots of machines to get a reasonable amount of energyThe machines costs a lot of moneyThe machines can look uglyThe machines can be damaged by storms
3 Tidal Energy – energy from sea tides Wave Energy – energy from sea wavesThe sea’s waves have kinetic energy. Using machines that bob up and down in the waves, this energy can be turned into electrical energy which we can use in our homes.Tidal Energy – energy from sea tidesIf you’ve ever been to the coast, you may have noticed that the sea level goes up and down, because of tides. When the tide is high, the water has lots of gravitational potential energy, which we can turn into electrical energy to use in our homes.At high tide, we trap the water behind a dam.At low tide, the water is released, and its energy is used to generate electricity.
4 Solar Energy – energy from the Sun Hydroelectric Energy – energy from riversThe water flowing in a river has kinetic energy. We can turn this into electrical energy to use in our homes. We usually need to build a dam, and let the water flow through it gradually.Solar Energy – energy from the SunThe Earth gets heat and light energy from the sun all the time. Can we use it – yes we can! The Sun’s energy can either be:changed into electrical energy to use in homes, using solar cells;or used to heat water for homes, using solar panels.
5 RenewableNo pollution, because nothing gets burnedWe can store the water up high, and then whenever we need the energy we can let the water outCosts a lot of money to build a damThe dam can ruin the local environment, because it changes where the water naturally flows. Some animals and plants may die.RenewableNo pollution, because nothing gets burnedReliable, because there are always two tides every dayCheap to run, once it’s builtCosts a lot to build the damThe dam may cause local floodingVery few suitable locations
6 No pollution, because nothing gets burned RenewableNo pollution, because nothing gets burnedSolar cells and solar panels are expensiveOnly works if it’s sunny! (it is UNRELIABLE)RenewableNo pollution, because nothing gets burnedTurbines are quite cheap and easy to build, so they can be used even in poor countriesTurbines can be ugly and noisyOnly works if it’s quite windy! If the wind stops, you get no energy (it is UNRELIABLE)
7 Biomass Energy – energy from plants The chemical potential energy stored in things that were once alive (e.g. trees) can be turned into heat energy by burning them. We can then turn the heat energy into electrical energy in biomass power stations.Trees absorb the sun’s energy. The trees change this energy into chemical energy, which they store inside themselves.When we burn wood, we turn this energy into heat, which is useful for cooking and heating.
8 Renewable – as long as we keep planting trees to replace the ones we cut down Doesn’t need any special equipment, so it can be used very easily, even in poor countriesDoesn’t add to the greenhouse effect (carbon neutral)Large areas of land are needed to grow enough treesUranium is very cheapDoes not produce CO2 or SO2 so doesn’t add to the greenhouse effect or cause acid rain.Very ReliableProduces small amounts of wasteNuclear Power is non-renewableLong start-up timeNuclear waste must be buried deep underground because it is dangerous to living things.If something does go wrong, a nuclear accident can be a major disasterRequires large amounts of water for cooling
9 Coal, Oil, Gas– energy from fossilised plants Nuclear Energy– energy from uraniumThe splitting of a radioactive atom (Uranium) into two smaller atoms produces a LOT of Energy. This nuclear energy can be easily turned into heat energy in water. The water then turns to steam which can generate electrical energy by a turbine.Coal, Oil, Gas– energy from fossilised plantsThe chemical potential energy stored in things that were once alive (e.g. trees) can be turned into heat energy by burning them. We can also turn it into electrical energy in Coal, Oil, or Natural Gas power stations.Trees absorb the sun’s energy. The trees change this energy into chemical energy, which they store inside themselves.Over thousands of years, heat and pressure underground can turn buried plants and animals into coal, oil, or natural gas.
10 Cheap source of energyLow start-up timeVery reliableNon-Renewable.Produces CO2 which adds to the greenhouse effect.Produces SO2 which causes acid rain.