Superior School of Commerce “Nicolae Kretzulescu ”

1. Superior School of Commerce “Nicolae Kretzulescu” Renewable energy sources Coordinating teacher: Student: Cuatu Georgeta Popescu Stefania Class: 12 G

2. Argument I have chosen this subject because I am interested in clean , green and renewable energy which can help our society survive longer. We live in a world affected by dangerous gases and polution. Using alternative energy sources we can prolongue our lives by keeping the planet healthier.

3. Contents • Forms of renewable energy • Renewable technologies • Renewable energy commercialization • Constraints and opportunities • Conclusion • Bibliography

4. Forms of renewable energy 1.Wind poweris renewable and produces no greenhouse gases during operation, such as carbon dioxide and methane. 2.Hydropower-energy in water can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. 3.Solar energyis the energy derived from the sun through the form of solar radiation. 4.Geothermal energy is energy obtained by tapping the heat of the earth itself, both from kilometers deep into the Earth's crust in some places of the globe or from some meters in geothermal heat pump in all the places of the planet .

5. Renewable technologies 1.Ocean thermal energy conversion uses the temperature difference that exists between deep and shallow waters to run a heat engine. 2.Osmotic power is the energy retrieved from the difference in the salt concentration between seawater and river water. 3.Microbial fuel cell is a bio-electromical system that drives a current by mimicking bacterial interactions found in nature- converting chemical energy to electrical energy by the catalytic reaction of microorganisms.

6. Renewable energy commercialization • World's largest photovoltaic power plants • Use of ethanol for transportation • Geothermal energy prospects • Wave farms expansion • Developing country markets

7. Constraints and opportunities 1.Availability and reliability- There is no shortage of renewable energy - however, converting that energy to a usable form in acceptable ways and transporting it to consumers has so far limited the use of renewables. 2.Land area required-One environmental issue, particularly with biomass and biofuels, is the large amount of land required to harvest energy, which otherwise could be used for other purposes or left as undeveloped land 3.Hydroelectricity-Hydroelectric power can be far less expensive than electricity generated from fossil fuels or nuclear energy, and areas with abundant hydroelectric power attract industry. 4.Wind farms-Wind power is one of the most environmentally friendly sources of renewable energy. It generates the energy used in its construction in just 3 months of operation, yet its operational lifetime is 20–25 years.

8. Conclusion I consider that renewable energy is being more and more used and in the future conventional energy will be replaced by it due to the fact that it is far more reliable does not produce residue and costs less to create and distribute.

9. Bibliography 1.     1.http://www.ren21.net/REN21Activities/Publications/GlobalStatusReport/GSR2010/tabid/5824/Default.aspx 2.      2.http://en.wikipedia.org/wiki/Renewable_energy 3.      3.www.ren21.net Renewabled Global Status Report:2009 4.      4.http://www.gwec.net/uploads/media/07-02_PR_Global_Statistics_2006.pdf 5.      5.http://en.wikipedia.org/wiki/List_of_photovoltaic_power_stations 6.Solar power plants