Renewable sources of energy

1. Renewable sources of energy BTEC First Engineering • The world needs more and more energy every day • Traditional way to generate (get) energy involve burning Fossil Fuels (Oil, Coal, Gas) • When fossil fuels are burned, they release CARBON DIOXIDE (CO2) into the atmosphere • Carbon Dioxide emissions increase “The Greenhouse Effect” where the global temperature rises. • This Climate change will cause huge environmental problems such as drought, extreme weather systems, rising sea levels and changing ecosystems • Increasingly countries are looking to renewable sources of energy to full their need for energy without contributing to climate change or running down their supplies of fossil fuels • A truly renewable energy source should be SUSTAINABLE, meaning it should be able to be used for years and years into the future without running out or harming the environment.

2. Renewable sources of energy Solar BTEC First Engineering The 4 main Renewable Sources of Energy are… Wind Hydro Geothermal

3. Wind Energy BTEC First Engineering • Wind Turbines are a natural and clean source of renewable energy that produce no air or water pollution. • The largest wind turbines generate enough electricity to power small towns and villages. • Wind Farms sometimes contain hundreds of turbines and are usually positioned in windy areas. Sometimes they are positioned off shore. • Only work when and where it’s windy: High Ground & Offshore • Many governments offer incentives for companies to use wind turbines however some people think they are ugly and spoil the landscape. • The constant spinning causes noise pollution • Land used for wind farms can still be used for agriculture & farming. https://www.youtube.com/watch?v=8PE69jcleKg

4. Solar Energy: Solar PhotoVoltaic Cells BTEC First Engineering • Solar PhotoVoltaic (Solar PV) cells convert the heat produced from the rays of sun into electricity. • The electricity produced can be used to power a homes/businesses and feed into the National Grid. • Solar PV Cells initially cost thousands of pounds to install, but they can significantly reduce electricity bills. • There has recently been an increase in the use of photovoltaic cells due to government subsidies (where the government adds to the amount that someone gets paid for the energy they generate.) • Disadvantages are their high cost to install and some people think they are ugly. Need to be SOUTH FACING. • Today, a lot of products use solar cells or panels to power everyday products, such as torches, mobile phones, and outdoor lights. This is because BATTERIES can store the electricity produced to use at night time. • Solar PV Cells are not to be confused with Solar Water Heaters https://www.youtube.com/watch?v=4pnll5qLIgg

5. Solar Energy: Solar Water Heaters BTEC First Engineering • Solar Water Heaters do not generate or use electricity • They use the energy from to the sun to heat water directly which can be pumped and stored for domestic use: baths, showers washing up etc. • Dark pipes in glass containers heat up due to the power of the sun, similar to how the greenhouse effects works, trapping the heat inside the glass which is then absorbed by the pipes. https://www.youtube.com/watch?v=-Lovrsjeh9g

6. Hydro Energy BTEC First Engineering • Hydroelectricity uses moving water-from a small stream, a large river or ocean waves to generate electricity. • As water flows downhill it generates potential energy. Hydropower systems convert this potential energy into kinetic energy using a turbine. • As water passes through a turbine, it spins the propeller blades which are connected to a generator, which produces electricity. • The faster the it flows, the more energy is produced. • HydroElectric Dams: turbines are built at the base of a dam and water is released steadily to generate electricity 24 hours a day with no air or water pollution. • Disadvantages: high initial cost of producing the facilities and in dry periods general water usage will need to be controlled around the country to ensure there is enough water to keep producing electricity. Dam Tidal Barrage Wave https://www.youtube.com/watch?v=Pj4dZM4SIls

7. Geothermal Energy BTEC First Engineering • This system uses heat from rocks in the earth’s inner core that turns water into steam. • Engineers drill down into the hot regions and the purified steam rises to drive turbines that produce electricity. Where there is no natural ground water, cold water can be pumped down to create steam. • This form of energy does not produce any pollution so does not contribute to the greenhouse effect. • There is no fuel required to run a geothermal power station and once built, the running costs are very low. • Geothermal Power Stations can only be built where there is a lot of heat close to the surface of the earth, (often where volcanoes are) such as Iceland. Because of this it is not common in the UK https://www.youtube.com/watch?v=J7sYu9sHObs

8. Discussion Points BTEC First Engineering • Which sources of energy are the most suitable for the UK? • Which sources of energy are the most reliable? • Which sources of energy are best for the environment? • Is our current energy use sustainable???

9. Example Questions BTEC First Engineering ?? ??

10. Example Questions BTEC First Engineering ?? ??