By: Jorge Marín and Fernando Martín RENEWABLE ENERGY By: Jorge Marín and Fernando Martín

Just a few info to start A Renewable energy is an energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat. About 16% of global final energy consumption comes from renewable, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity. New renewable (small hydro, modern biomass, wind, solar, geothermal, and biofuels) accounted for another 3% and are growing very rapidly.

Wind Power Wind power is the conversion of wind energy into a useful form of energy. For example: wind turbines to make electricity.  windmills for mechanical power. wind pumps for water pumping or drainage. sails to propel ships.

Wind Farms A large wind farm may consist of several hundred individual wind turbines which are connected to the electric power transmission network. Later the electricity created by this turbines will be transported to all the cities near there. Many of the largest operational wind farms are located in the USA and China.

Environmental Effects Compared to the environmental impact of traditional energy sources, the environmental impact of wind power is relatively minor. Wind power consumes no fuel, and emits no air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months. Although a wind farm may cover a large area of land, many land uses such as agriculture are compatible.

In the future Globally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand. This could require wind turbines to be installed over large areas, particularly in areas of higher wind resources.

Hydropower Hydropower or water power is power derived from the energy of falling water. The term is used almost exclusively in conjunction with the modern development of hydro-electric power.

Types of Hydropower Conventional hydroelectric, referring to hydroelectric dams. Run-of-the-river hydroelectricity, which captures the kinetic energy in rivers or streams, without the use of dams. Small hydro projects are 10 megawatts or less and often have no artificial reservoirs. Micro hydro projects provide a few kilowatts to a few hundred kilowatts to isolated homes, villages, or small industries. Pumped-storage hydroelectricity stores water pumped during periods of low demand to be released for generation when demand is high.

Solar energy Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar energy technologies include solar photovoltaics (PV) and Solar thermal energy (STE).

Photovoltaics Photovoltaics (PV) is a method for generating electric power by using solar cells to convert energy from the sun into a flow of electrons. Photovoltaics power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Materials presently used for photovoltaics include monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium gallium selenide/sulfide.

Solar cells produce direct current electricity from sun light, which can be used to power equipment or to recharge a battery. The first practical application of photovoltaics was to power orbiting satellites and other spacecraft.

More than 100 countries use solar PV. Solar photovoltaics is growing rapidly to a total global capacity of 67,400 megawatts (MW) at the end of 2011, representing 0.5% of worldwide electricity demand. More than 100 countries use solar PV. Map of solar electricity potential in Europe.

Installations may be ground-mounted (and sometimes integrated with farming and grazing) or built into the roof or walls of a building (building-integrated photovoltaics).

Solar thermal energy (STE) Solar thermal energy (STE) is a technology for harnessing solar energy for thermal energy (heat).

Solar thermal collectors can be: Low-temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plates but are used for heating water or air for residential and commercial use.

High-temperature collectors concentrate sunlight using mirrors or lenses and are generally used for electric power production. STE is different from and much more efficient than photovoltaics.

Biomass Energy converted by vegetation Ecologic energy Teorically infinite

Biomass Most common form of obteining biomass is from forests Specific growings Excrements

Biofuel Fuel Bioethanol and biodiesel Bioethanol is formed by sugars Byodiesel came from vegetal oils

Pros and cons NOT an ecologic energy Not whorthwile Less toxic than oil and fuel

Geothermal Came from the heat of the earth Two tipes of thermal area Hidrothermal Hidroelectric

Pros and cons Practically no waste Much more abundant than oil It can’t be transported Leaves a contaminated water

Information from: http://en.wikipedia.org/wiki/Renewable_energy http://www.sciencedaily.com/news/earth_climate/renewable_energy/ http://www.reegle.info/index.php?searchTerm=renewable%20energy%20for%20kids&site=clean_energy_search&search=Search&gclid=CJCXy8bKmbACFdKBfAodrEF0ZA