Wind Power Basic Information
• Why Wind?
• What is Wind Energy?
• Wind Energy is Versatile
• Wind Energy is Clean and Renewable
• Wind Features
• Wind Turbines
• Wind Farms
• Wind Farm Site
• How Wind Turbines Work
• Advantages and Challenges of Wind Energy
• The Future Growth of Wind Energy in Puerto Rico
Almost everyone has sunlight available but not everyone has strong winds able to generate wind power. To those who have this resource, if properly analyzed and engineered, can be developed in order provide a large amount of power at a fraction of the cost of photovoltaic systems. Read all about it in here, and, if you think you may have wind resources that can be harvested, give us a call at emg@EnergySavingsEngineering.com
What is Wind Energy?
You will feel that you can’t stand steady, that is mean wind has its power. Wind energy is kinetic energy that is present in moving air that is mean air horizontal movement produced its power.
We have been harnessing the wind's energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill's modern equivalent – a wind turbine - can use the wind's energy to generate electricity. Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind's energy with their propeller-like blades. Usually three blades are mounted on a shaft to form a rotor.
A blade acts much like an airplane wing. When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift. The force of the lift is actually much stronger than the wind's force against the front side of the blade, which is called drag. The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity. Wind turbines can be used as stand-alone applications, or they can be connected to a utility power grid or even combined with a photovoltaic (solar cell) system.
SPECIAL NOTE: notice that the wind power is proportional to the CUBE of the Wind speed. Thus if there were two different sites or conditions (such as a change of height) and available wind were to increase from an average wind speed of 6 MPH to 8 MPH the equivalent power available would be (6*6*6)=216 vs. (8*8*8)=512 and the difference in available power would increase by (512/216)= 237%
Wind Energy is Versatile
When air moves, causing wind, it gathers kinetic energy—the energy created whenever mass is in motion. With the right technology, the wind’s kinetic energy can be captured and converted to other forms of energy such as electricity or mechanical power. That’s wind power. Just as the earliest windmills in Persia, China and Europe used wind power to pump water or grind grain, today’s utility-connected wind turbines and multi-turbine wind farms use wind power to generate clean, renewable energy to power homes and businesses.
Wind Energy is Clean and Renewable
Wind energy should be considered an important component of any long-term energy strategy, because wind energy generation uses a natural and virtually inexhaustible source of power—the wind—to produce electricity. That is a stark contrast to traditional power plants that rely on fossil fuels. And wind energy generation is clean; it doesn’t cause air, soil or water pollution. That’s an important difference between wind energy and some other renewable energy sources, such as nuclear power, which produces a vast amount of hard-to-manage waste.
Wind is nature phenomenon, has its features, it is usually measured in meters per second (M/S), miles per Hour (MPH), feet per seconds (FT/S) or in Knots (KTS). Usually, we use wind speed, wind direction, wind frequency to express wind features.
Wind speed: Is a term about the movement of air from one place to the next. As the wind is changeable, usually, what we said wind speed is the average value of various instantaneous wind speed in a period time, which is mean average wind speed. Wind speed can be measured by an anemometer. Wind speed changes depend on the height. The wind speed is increased as the height increase. As a guide a wing study has to be performed at the desired site with a minimum duration of 1 yr.
Wind frequency: To be wind speed frequency and wind direction frequency.
Wind speed frequency: The frequency extent of different wind speed , wind generator operate smooth and it is easily to be control when the average wind speed is high, but the wind speed is stable.
Wind direction frequency: The frequency extent of different wind direction. To be wind generator, hope always a certain wind direction frequency to be large.
Wind turbine is a machine that converts the wind's kinetic energy into rotary mechanical energy, which is then used to do work. The rotational energy is converted into electricity by using a generator.
The most familiar forms of wind turbines are the horizontal axis ones that look like conventional windmills. Vertical axis ones, some of which look like egg beaters, also are in use but they are few in number.
The principle of wind turbines is very simple. Just as wind energy is utilized to make a sailboat move over water; wind energy is used to run large fans and turbines. When any object is placed in the path of the wind, the wind pushes it and, in the process, transfers some of its own power to the object. If this object is specifically engineered to provide lift, the object will move.
The turbines are usually pointed upwind as turbine towers produce a lot of air turbulence at the rear of it. The blades of a turbine are made very stiff to avoid the blades being blown towards the tower by fast winds. They are also placed at a good distance from the tower and angled to a degree to prevent them from snapping off and damaging the tower housing.
In the case of turbines, each blade in the rotor is designed for lift allowing the rotor to rotate. This rotation drives a low velocity shaft attached to a gear coupled to a high velocity shaft that eventually ends in the generator housing.
The magnetic rotor located on the end of the high speed shaft spins inside of a series of loops of copper wire wound around an iron cast. When the rotor starts to spin, electromagnetic induction takes place producing the electric current. This current is either then fed into the power grid (direct connection) or passed through a series of electronic components (indirect connection) and transformed into something useful.
Wind farms are groups of wind turbines located in the same site for the purpose of producing electric power for a certain community. The individual turbines are connected to one another and usually a medium voltage power collection system and communication network are used. Wind farms may be composed of a few dozen to hundreds of wind turbines scattered at an extensive area of hundreds of miles. Though a wide area is needed for a wind farm, the lands between wind turbines can still be utilized for agricultural purposes. In most cases, wind farms are built offshore, this is mostly because the winds tend to be stronger and less turbulent.
Wind Farm Site
An ideal wind farm site is located in an area which has consistent strong wings, has no obstructions nearby, is close to sea level and is also near the utility grid where it will feed the created electrical energy.
How Wind Turbines Work
Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetation. Humans use this wind flow, or motion energy, for many purposes: sailing, flying a kite, and even generating electricity.
The terms wind energy or wind power describes the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be readily used, when coupled with a generator in order to convert the same into electricity.
So how do wind turbines make electricity? Simply stated, a wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Advantages, Myths and Challenges of Wind Energy
Wind Power is the most efficient of all of the renewable energy technologies
Use proven reliable technology and are tested to international standards (which also include surviving hurricane type wind loads)
The wind is free and is a renewable resource, with modern technology it can be captured efficiently
Once the wind turbine is built the energy it produces does not cause green house gases or other pollutants.
Although wind turbines can be very tall each takes up only a small plot of land. This means that the land below can still be used. This is especially the case in agricultural areas as farming can still continue.
Many people find wind farms an interesting feature of the landscape.
Remote areas that are not connected to the electricity power grid can use wind turbines to produce their own supply.
Wind turbines have a role to play in both the developed and third world.
Wind turbines are available in a range of sizes which means a vast range of people and businesses can use them. Single households to small towns and villages can make good use of range of wind turbines available today.
1. The strength of the wind is not constant and it varies from zero to storm force. This means that wind turbines do not produce the same amount of electricity all the time. There will be times when they produce no electricity at all.
2. Many people feel that the countryside should be left untouched, without these large structures being built. The landscape should left in its natural form for everyone to enjoy.
3. Wind turbines are noisy. (See Turbine myths below)
4. Many people see large wind turbines as unsightly structures and not pleasant or interesting to look at. They disfigure the countryside and are generally ugly.
5. When wind turbines are being manufactured some pollution is produced. Therefore wind power does produce some pollution.
C) Wind Turbines Myths
Wind Turbines are Noisy: In reality wind turbine are quiet: They noise generated by large wind turbines could be compared to the noise generated by a common refrigerator in a quiet room.
Nearby Residences Will be Affected by Shadow Flicker: Shadow flicker is almost never a problem for residences near a wind farm. This can easily be avoided with the proper siting and setback from whichever turbine might be closer no nearby housing areas.
Turbine Interfere with TV and Other Communications Signals: Interference is rare and easily avoided. In case that a wind turbine might be in the “line of sight” of any microwave pass” proper coordination and moving the turbine just a small distance will avoid this potential problem.
Turbines Are Ugly: Beauty is on the eye of the beholder. Many people feel that wind turbines are majestic. Careful design of a wind project can alleviate many visual concerns.
Wind Turbines May Throw Blades or Collapse: Modern wind turbines are so safe that hey successfully operate near schools, in urban settings and in densely populated areas. Modern blades are certified to international engineering standards.
Wind Turbines Harm Wildlife: Wind energy development’s overall impact on birds or bats is extremely low compared to other human-related activities. For every 10,000 birds killed by human activities (mostly by household cats and glass doors and windows) less the one (1) fatality can be attributed to a wind turbine.
Wind Turbines are Inefficient: The fact is that wind turbines are very efficient and that is part of their beauty. Power derived from wind generators is more efficient that any other renewable energy source.
Wind power must compete with conventional generation sources on a cost basis. Depending on how energetic a wind site is, the wind farm may or may not be cost competitive. Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators.
Good wind sites are often located in remote locations, far from cities where the electricity is needed. Transmission lines must be built to bring the electricity from the wind farm to the city.
Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation.
Although wind power plants have relatively little impact on the environment compared to other conventional power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants.
The Future Growth of Wind Energy in Puerto Rico
Wind Generator installed at the Bacardi site, Cataño, PR
According to a recent study by the University of Puerto Rico, College of Engineering and Mechanical Arts at Mayaguez, PR, the “...potential wind energy available in Puerto Rico is around 13,725 MW, even if we were able to achieve 10% would still be a considerable amount”.
As the need for clean, renewable energy increases, and the world more urgently seeks alternatives to finite supplies of oil, coal and natural gas, priorities will change. And as the cost of wind energy continues to decline, due to technology improvements and better generation techniques, wind power will become increasingly feasible as a major source of electricity and mechanical power.
If you desire more information regarding this subject please contact us at emg@EnergySavingsEngineering.com for a no cost consultation.