project work..plss help!!?
hello guys.. i hv to make a project on wind energy..n it should be very innovative…different from the common ideas…please suggest me.!! n it should b working project.
Windmill Farms answers:
Wind power is the conversion of wind energy into a useful form, such as electricity, using wind turbines. At the end of 2007, worldwide capacity of wind-powered generators was 94.1 gigawatts. Although wind currently produces about 1% of world-wide electricity use, it accounts for approximately 19% of electricity production in Denmark, 9% in Spain and Portugal, and 6% in Germany and the Republic of Ireland (2007 data). Globally, wind power generation increased more than fivefold between 2000 and 2007.
Most wind power is generated in the form of electricity. Large scale wind farms are connected to electrical grids. Individual turbines can provide electricity to isolated locations. In windmills, wind energy is used directly as mechanical energy for pumping water or grinding grain.
Wind energy is plentiful, renewable, widely distributed, clean, and reduces greenhouse gas emissions when it displaces fossil-fuel-derived electricity. The intermittency of wind seldom creates problems when using wind power to supply a low proportion of total demand, but it presents extra costs when wind is to be used for a large fraction of demand. However these costs even for quite large percentage penetrations are considered to be modest.
The siting of turbines has become a controversial issue amongst those concerned about the value of natural landscapes, particularly since the best sites for wind generation tend to be in scenic mountain and oceanside areas.
Main article: History of wind power
The earliest historical reference to a rudimentary windmill was used to power an organ in the 1st century AD. The first practical windmills were later built in Sistan, Afghanistan, from the 7th century. These were vertical-axle windmills, which had long vertical driveshafts with rectangle shaped blades. Made of six to twelve sails covered in reed matting or cloth material, these windmills were used to grind corn and draw up water, and were used in the gristmilling and sugarcane industries. Horizontal-axle windmills were later used extensively in Northwestern Europe to grind flour beginning in the 1180s, and many Dutch windmills still exist.
In the United States, the development of the “water-pumping windmill” was the major factor in allowing the farming and ranching of vast areas of North America, which were otherwise devoid of readily accessible water. They contributed to the expansion of rail transport systems throughout the world, by pumping water from wells to supply the needs of the steam locomotives of those early times.
The multi-bladed wind turbine atop a lattice tower made of wood or steel was, for many years, a fixture of the landscape throughout rural America.
The modern wind turbine was developed beginning in the 1980s, although designs are still under development.
For more details on this topic, see Wind.
The origin of wind is complex. The Earth is unevenly heated by the sun resulting in the poles receiving less energy from the sun than the equator does. Also the dry land heats up (and cools down) more quickly than the seas do. The differential heating drives a global atmospheric convection system reaching from the Earth’s surface to the stratosphere which acts as a virtual ceiling. Most of the energy stored in these wind movements can be found at high altitudes where continuous wind speeds of over 160 km/h (100 mph) occur. Eventually, the wind energy is converted through friction into diffuse heat throughout the Earth’s surface and the atmosphere.
There is an estimated 72 TW of wind energy on the Earth that potentially can be commercially viable. Not all the energy of the wind flowing past a given point can be recovered (see Betz’ law).
How would you compare ocean energy and wind energy?
maybe in paragraph form or in dotted form like
Windmill Farms answers:
The ocean can produce two types of energy: thermal energy from the sun’s heat, and mechanical energy from the tides and waves.
Oceans cover more than 70% of Earth’s surface, making them the world’s largest solar collectors. The sun’s heat warms the surface water a lot more than the deep ocean water, and this temperature difference creates thermal energy. Just a small portion of the heat trapped in the ocean could power the world.
Ocean thermal energy is used for many applications, including electricity generation. There are three types of electricity conversion
systems: closed-cycle, open-cycle, and hybrid. Closed-cycle systems use the ocean’s warm surface water to vaporize a working fluid, which has a low-boiling point, such as ammonia. The vapor expands and turns a turbine. The turbine then activates a generator to produce electricity. Open-cycle systems actually boil the seawater by operating at low pressures. This produces steam that passes through a turbine/generator. And hybrid systems combine both closed-cycle and open-cycle systems.
Ocean mechanical energy is quite different from ocean thermal energy. Even though the sun affects all ocean activity, tides are driven primarily by the gravitational pull of the moon, and waves are driven primarily by the winds. As a result, tides and waves are intermittent sources of energy, while ocean thermal energy is fairly constant. Also, unlike thermal energy, the electricity conversion of both tidal and wave energy usually involves mechanical devices.
A barrage (dam) is typically used to convert tidal energy into electricity by forcing the water through turbines, activating a generator. For wave energy conversion, there are three basic systems: channel systems that funnel the waves into reservoirs; float systems that drive hydraulic pumps; and oscillating water column systems that use the waves to compress air within a container. The mechanical power created from these systems either directly activates a generator or transfers to a working fluid, water, or air, which then drives a turbine/generator.
Wind energy is the kinetic energy associated with the movement of atmospheric air. It has been used for hundreds of years for sailing, grinding grain, and for irrigation. Wind energy systems convert this kinetic energy to more useful forms of power. Wind energy systems for irrigation and milling have been in use since ancient times and since the beginning of the 20th century it is being used to generate electric power. Windmills for water pumping have been installed in many countries particularly in the rural areas.
Wind turbines transform the energy in the wind into mechanical power, which can then be used directly for grinding etc. Or further converting to electric power to generate electricity. Wind turbines can be used singly or in clusters called ‘wind farms’. Small wind turbines called aero-generators can be used to charge large batteries.
Five nations – Germany, USA, Denmark, Spain and India – account for 80% of the world’s installed wind energy capacity. Wind energy continues to be the fastest growing renewable energy source with worldwide wind power installed capacity reaching 14,000 MW.
Realizing the growing importance of wind energy, manufacturers have steadily been increasing the unit size of the wind electric generators since the late 1980s. Another important development has been the offshore (i.e. In the sea) wind farms in some regions of Europe, which have several advantages over the on-shore ones. The third major development has been the use of new techniques to assess the wind resource for techno-commercial viability.
what are the technical details of generating electricity from wind power?
Windmill Farms answers:
Wind hits fan blades which turn (slowly)
gearing raises the speed to something useful for the generator.
Generator spins. And creates electricity.
Now as a generator increases its output volts with increasing speed we either need a voltage regulator, or a mechanical speed control.
Finally as the wind has more energy at higher wind speeds we need some way of balancing the load currents to the power available.
Either maintain constant load and use blade feathering to reduce the power collected,
or have some type of sink that can accept whatever power you can make available.
Usually this is the electricity grid. In rural areas this has been used for close to a hundred years charging batteries as the sink for power available.
If the batteries are fully charged then either the blades are turned away from the wind, ( not nice as someone has to climb a ladder to do it) or simply switch off the generator and let the blades turn freely ( not good as they can overspeed and damage themselves.)
Commercially controlled feathering of the blades solves the problem.
how does power wind mill works? can it be used for rural area electric supply?
Windmill Farms answers:
The rotational energy of the blades turns a pulley on an auto
alternator to produce 12 volts DC…
what are the benefits of renewable resources in south africa?
what are the advantages of putting up wind electricity and solar electricity
Windmill Farms answers:
Over the past decade, global use of renewable energy sources (solar, wind, hydropower, geothermal, biomass, and biofuel) for generation of electricity has grown significantly, reaching 19% of total power generation in 2010 compared with 14% in 2002. The rise in the use of renewable energy has mainly been driven by increased awareness of effects of climate change and governments’ incentive programs aimed at enhancing the development and the use of green energy.
Potential benefits of renewable energy to Africa
Renewable energy sources offer numerous benefits ranging from contributing to economic growth through the creation of new enterprises and jobs to mitigating the effects of climate change and providing electricity to rural areas.
The fast global growth of the renewable energy industry would foster economic growth mainly through investment and direct and indirect jobs creation.
According to the United Nations Industrial Development Organization (UNIDO), 26% of the total reduction in carbon emissions worldwide in 2010 was on account of efficiency gains in renewable energy sources. Increasing the share of renewable energy as a source of power generation will likely accelerate further reductions in these emissions.
In rural areas, the transmission and distribution of power generated from fossil fuels is very costly.
Therefore, using off-grid renewable energy sources in rural areas will help increase access to basic services, including lighting, communications, and water pumping. The use of these increasingly affordable technologies would facilitate the integration and development of African rural populations.
Impediments to the development of renewable energy in Africa
Many factors may compromise the development of renewable energy in Africa:
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