Edison
Wind 101
Solar & Wind
WIND 101
Wind is created by unequal heating of the earth’s surface causing the air to flow from one location to another. Wind turbines work by converting the kinetic energy in wind into mechanical power that turns blades. The blades are attached to a shaft that drives a wind generator or alternator resulting in the production of electricity. Aside from the generating source, the components of a wind energy system are similar to that of a solar system as presented in "Solar 101" webpage.
TURBINE
The main component of a wind electrical generating system is the turbine. Turbines consist of a rotor which usually has two or three blades, the nacelle which contains the generator or alternator to which the rotor is attached to a tail or other device to correctly orient the turbine to the wind.
Turbines come in many different sizes from micros with blade diameters of inches to large megawatt turbines with blade diameters measuring more than a hundred feet. Most turbines have a horizontal axis with blades turing in front of the tower, called upwind turbines, or with blades turing behind the tower called downwind turbines.
TOWER
Turbines are fastened on top of towers which are of two types guide wire and free standing. Guide wire towers consist of small poles that can be repeatedly raised and lowered for service without too much effort. Once the pole is vertical it is stabilized with several guide wires that are attach to anchors placed in the ground. This type of tower is used primarily for small with turbines. Free standing towers have no guide wires and are of two types, pole and lattice. Pole towers are usually constructed of steel bolted to a cement foundation, round in shape, and are not normally taken down for maintenance. Lattice towers like pole towers stand alone and are also not usually taken down for maintenance. They are also made of steel with a more elaborate lattices construction resulting in many connecting points giving rise to more water retaining areas for greater potential corrosion. They are normally cheaper that pole towers.
REMAINING COMPONENTS
The remaining components of a wind power generating system in most cases are the same as those shown in the diagram on the "Solar 101" webpage. Simply substitute a turbine on a tower for the solar panel in the drawing and explanation and the rest is the same.
Wind is created by unequal heating of the earth’s surface causing the air to flow from one location to another. Wind turbines work by converting the kinetic energy in wind into mechanical power that turns blades. The blades are attached to a shaft that drives a wind generator or alternator resulting in the production of electricity. Aside from the generating source, the components of a wind energy system are similar to that of a solar system as presented in "Solar 101" webpage.
TURBINE
The main component of a wind electrical generating system is the turbine. Turbines consist of a rotor which usually has two or three blades, the nacelle which contains the generator or alternator to which the rotor is attached to a tail or other device to correctly orient the turbine to the wind.
Turbines come in many different sizes from micros with blade diameters of inches to large megawatt turbines with blade diameters measuring more than a hundred feet. Most turbines have a horizontal axis with blades turing in front of the tower, called upwind turbines, or with blades turing behind the tower called downwind turbines.
TOWER
Turbines are fastened on top of towers which are of two types guide wire and free standing. Guide wire towers consist of small poles that can be repeatedly raised and lowered for service without too much effort. Once the pole is vertical it is stabilized with several guide wires that are attach to anchors placed in the ground. This type of tower is used primarily for small with turbines. Free standing towers have no guide wires and are of two types, pole and lattice. Pole towers are usually constructed of steel bolted to a cement foundation, round in shape, and are not normally taken down for maintenance. Lattice towers like pole towers stand alone and are also not usually taken down for maintenance. They are also made of steel with a more elaborate lattices construction resulting in many connecting points giving rise to more water retaining areas for greater potential corrosion. They are normally cheaper that pole towers.
REMAINING COMPONENTS
The remaining components of a wind power generating system in most cases are the same as those shown in the diagram on the "Solar 101" webpage. Simply substitute a turbine on a tower for the solar panel in the drawing and explanation and the rest is the same.
MAINTENANCE
Wind turbines are machines. They require maintenance and wear out and are similar to a generator or alternator in motor vehicles. Instead of being driven by an engine belt, they are driven by wind turning a shaft by means of blades. Turbine shafts turn on bearings which, along with the generator components, wear out. Like with a car generator or alternator, the rotor and nacelle must periodically be removed to replace bearings and/or generator components. With most turbines, at least annual maintenance is required in the nacelle to lubricate the moving parts and change the oil if there is a gear box. Towers may need attention to prevent rusting, and bolts need to be checked for tightness. Both maintenance and repairs require either lowering the tower or getting to the top of a pole or lattice tower by ladder or crane. Thus, there is continuing expense with wind turbines after installation.
WHEN BUYING A WIND TURBINE
A short list would include: how many blades they have, upwind or down wind design, shaft rotation speed (faster rotation speed usually means more wear and a shorter life span) and in that regard transmission or direct drive, whether the rotor is self starting or needs power assistance, rotor diameter, yawing technique to reduce potential turbine destruction in high winds, generator capacity, parking break for repairs, lightening management, noise, start-up speed, and quality of construction (as a general rule heaver is better).
Additional considerations for a wind electrical generating system are; wind quality and therein tower height, tower location so that the topography and any surrounding obstacles do not reduce the wind striking the rotor, wildlife considerations, and esthetics. The two main determinates of power production by a wind turbine are rotor diameter (sweep area) and wind quality.
WIND OR SOLAR AS A GENERATING SOURCE
Solar electric generating systems have no moving parts and require almost no maintenance leaving little cost after installation. Solar component warranties are much longer than wind turbines although properly maintained towers should last decades. The amount and location of wind is harder to determine than the location and pattern of the sun because it can be seen. Consequently, there is little question about location for solar panel placement, where as wind location is more amorphous. Although wind maps are improving, for best results wind testing should precede installation of a turbine. Large electrical demands are harder to obtain from solar because of panel size area requirements. Location of solar panels requires an un-shaded southern exposure for best results. Wind turbines must be positioned at the correct height and location for optimum production.
There are many more variables to consider with a wind generating system than with a solar system. It is therefore, harder to predict production outcome with a wind system which increases the possibility of failure to obtain expected results.
If the wind is blowing generation can occur around the clock whereas solar generation only occurs when the sun is shining on the solar panels.
In the Northern hemisphere, wind generation is better in the winter and solar generation in the summer. A hybrid system of solar and wind is a good choice for year round electric generation.
Wind turbines are machines. They require maintenance and wear out and are similar to a generator or alternator in motor vehicles. Instead of being driven by an engine belt, they are driven by wind turning a shaft by means of blades. Turbine shafts turn on bearings which, along with the generator components, wear out. Like with a car generator or alternator, the rotor and nacelle must periodically be removed to replace bearings and/or generator components. With most turbines, at least annual maintenance is required in the nacelle to lubricate the moving parts and change the oil if there is a gear box. Towers may need attention to prevent rusting, and bolts need to be checked for tightness. Both maintenance and repairs require either lowering the tower or getting to the top of a pole or lattice tower by ladder or crane. Thus, there is continuing expense with wind turbines after installation.
WHEN BUYING A WIND TURBINE
A short list would include: how many blades they have, upwind or down wind design, shaft rotation speed (faster rotation speed usually means more wear and a shorter life span) and in that regard transmission or direct drive, whether the rotor is self starting or needs power assistance, rotor diameter, yawing technique to reduce potential turbine destruction in high winds, generator capacity, parking break for repairs, lightening management, noise, start-up speed, and quality of construction (as a general rule heaver is better).
Additional considerations for a wind electrical generating system are; wind quality and therein tower height, tower location so that the topography and any surrounding obstacles do not reduce the wind striking the rotor, wildlife considerations, and esthetics. The two main determinates of power production by a wind turbine are rotor diameter (sweep area) and wind quality.
WIND OR SOLAR AS A GENERATING SOURCE
Solar electric generating systems have no moving parts and require almost no maintenance leaving little cost after installation. Solar component warranties are much longer than wind turbines although properly maintained towers should last decades. The amount and location of wind is harder to determine than the location and pattern of the sun because it can be seen. Consequently, there is little question about location for solar panel placement, where as wind location is more amorphous. Although wind maps are improving, for best results wind testing should precede installation of a turbine. Large electrical demands are harder to obtain from solar because of panel size area requirements. Location of solar panels requires an un-shaded southern exposure for best results. Wind turbines must be positioned at the correct height and location for optimum production.
There are many more variables to consider with a wind generating system than with a solar system. It is therefore, harder to predict production outcome with a wind system which increases the possibility of failure to obtain expected results.
If the wind is blowing generation can occur around the clock whereas solar generation only occurs when the sun is shining on the solar panels.
In the Northern hemisphere, wind generation is better in the winter and solar generation in the summer. A hybrid system of solar and wind is a good choice for year round electric generation.
Things To Know & Consider
