• Solar energy is a renewable resource.• No carbon dioxide emissions to add to the Greenhouse Effect• No sulphur dioxide emissions to cause Solar powered station, California acid rain.
• Solar panels can be quickly set up in remote areas • Local communities can benefit from small scale use of solar power. • Can be used to chargeSolar cells used to charge batteries batteries to provide electricity when needed.to charge = caricare
• The initial cost of solar cells can be very high.• The output is dependent on weather conditions and the time of day. Solar reflector used for cooking• Solar energy doesn’t work at night. Output = resa, produzione
Wind in the past We have used wind power for thousands of years but during the past 250 years steam engines, petrol engines and electricity took over from wind.
Wind ForeverWind is a renewableenergy resource. It is aregular part of ourweather, which is drivenby energy from the sun.So as long as the sunkeeps shining the windwill keep blowing.
Advantages Disavantages Renewable- as long The wind is not as the sun shines the always predictable – wind will blow some days have no Clean source- no wind. emissions of CO2, Suitable areas for SO2 and N0x wind are often near Government the coast, where initiatives to promote land is expensive. wind power
How ?The kinetic energy of thewind is converted intorotational kinetic energyof the turbine.The turbine drives thegenerator. The generatorconverts the kineticenergy into electricalenergyIn strong winds theblades of the turbine twistslightly. This slows theturbine down andprevents damage. slightly = lievemente
• Water in a high reservoir has potential energy• The water is allowed to fall under gravity• The water gains kinetic energy• The kinetic energy drives the turbines• The turbines drives the generators• The kinetic energy of the shafts of the generators is converted into electrical
• There is no air pollution• It is very reliable• Minimal running cost• No fuel needed.• There is an immediate response
• You have to flood a valley to build a big dam• there is a big impact on the environment• possible loss of habitat for some species• initial costs are high• an eyesore (= un pugno nell’occhio).