Articles in the Wind Turbine Category
Posted in Vertical Wind Generator, Wind Turbine on 28 February 2010
Vertical Turbine Generators (VAWTs) are a type of wind turbine generator that has the primary rotor shaft aligned in a vertical position. Using a vertical axis, both gearbox and generator can be situated at the ground; towers are not needed any more for mounting and are easy for maintenance. Drag might be produced when the blades oscillates into the wind.
Subtypes of Vertical Turbine Generators
- Darrieus wind generator – (Egg beater model) has good proficiency but is unreliable due to huge amount of torque surge and cyclic stress it produces on each tower. Also requires external power to start up.
- Giromill – a variation of the Darrieus turbine; it has straight blades, rather than curved ones. This model produces variable pitch which creates less torque throb and is self-out setting. The upper hand of variable pitch is: dynamic operation in fierce winds, high starting torque, less blade velocity proportion, high coefficient of performance. Straight V blades or curved ones can be used.
- Savonius wind generator – drag type model with two or numerous scoops that are serviced in anemometers. The turbine is self out-setting whenever there are three or more scoops. Sometimes, elongated helical scoops give the turbine smooth torque.
Advantages of VAWT
- The turbine designed to be used at ground level and uses less towers; more accessible of maintenance.
- Can be built on locations where towering buildings are not allowed and be in favor of hilltops, mesas and ridgelines.
- VAWT has decreased sound signature compared to other type of turbine.
- VAWT has lower start-up speed.
Posted in Wind Generator, Wind Turbine on 13 February 2010
Wind Turbine Generator is a mechanical rotating machine which converts kinetic energy from the wind into mechanical energy and then converted into useful electrical energy. Due to environmental and economical concerns, wind turbine can be an alternative source of energy and, does not produce harmful green house gases. Wind turbines especially in wind farm, require constant winds with high speeds; wind velocity and mass is also accounted in.
Wind turbines are constructed to capture and harness the wind energy that exists in a location. Through Aerodynamic modeling, one can determine the optimum tower height, blade number and control system.
20% of the total cost of the wind turbine is attributed to the rotor parts, which houses the wind generator turbine blades for transforming the kinetic energy of the wind into mechanical energy.
34% of the total cost of wind turbine is attributed to the generator component, consist of the electrical dynamo, and regulates electrical components and gearbox; which converts the mechanical energy from the turbine to electrical energy.
15% of the total cost, concerns with the wind turbine that comes from the structural support component, which accommodate the tower and rotor yaw apparatus.
31% is attributed to other parts.
Wind Turbine Generators has impact on wildlife. Noise from the turbine may disturb certain hearing sensitive animals, birds and bats are often killed from collision of the blade. High quality wind locations are often far and inhospitable; creating obstacles in transmission logistics and maintenance. How ever wind turbine has much more favorable life cycle imparts than other alternatives.
Posted in Micro Wind Generator, Solar Panel, Vertical Wind Generator, Wind Generator, Wind Turbine on 6 February 2010
Vertical Axis Wind Generator or Vertical Axis Wind Turbine (VAWT) is a type of wind turbine that has its rotor shaft position vertically. VAWTs do not need for towers because of this arrangement; generator and gear box are placed near ground level, which is more accessible for maintenance. VAWTs can also utilize wind from any directions. Drawbacks of VAWTs are some design produce pulsating pulse, affects reliability. Wind speeds are more slower at near ground level, so less energy is available to be harnessed by the turbine. Air flow near ground level and other objects can produce turbulent flow, which creates vibration, noise, and bearing wear which lowers reliability of the turbine. However when mounted on top of buildings, this can double the speed as the building redirects wind over the roof.
VAWT advantages:
- A large tower is less generally needed, VAWTs has mounted near ground level and roof tops.
- Models without yaw apparatus are plausible with secured pitch rotor concepts.
- VAWTs are located near ground level, which is more accessible for maintenance.
- VAWTs have lesser startup wind speeds. They can start generating electrical energy at around 6 mp/h (or 10 km/hr)
- VAWTs can be erected at locations where taller structures are not allowed.
- VAWTs tend to create lower noise.
VAWT disadvantages:
- VAWT are less efficient compared to the other type of wind turbine, because of further drag that is created when the blades rotate.
- VAWTs uses guy-wire to secure it, this places strain on the base bearing because the entire mass is on the bearing.
Posted in Micro Wind Generator, Vertical Wind Generator, Wind Generator, Wind Turbine on 31 January 2010
Due to declining natural resources such as fuel, people resort to alternative renewable energy resources. Wind power is one of the cleanest and most efficient alternative energy resources. Wind generators for residencial use are available commercially. They vary in size, model, price and output. All wind generators operates on the principle of using the kinetic energy of the wind, converting to mechanical energy and converting it to useful electrical energy.
Wind generators can save up to 50%-90% on electrical bill depending on several factors such as wind speed and generation output. Homes in United States use about 9,400 kilowatts-hour (kWh) of electricity per year. Depending on average wind speed in the area, a suitable wind turbine would be rated at the range of 5 to 15 kilowatts in order to make enough contribution to meet up the demand.
In buying a wind generator for home use, location is important; not suitable in urban and suburban area, an open area is required; wind generator is relatively a large device and a tower is needed. Also electricity price should be at least 10 cents/kWh. Wind speed is also important, recommended wind speed should not be below 7 to 15 mph.
Price range for wind generator is around $6,000 to $20,000 or more depending on model, size, output and service agreement by the manufacturer. Self installation is cheaper than manufacturer based installation providing you have knowledge on wind generator installation, however manufacturer installed are more hassle free and comes with support after the installation.
Posted in Wind Generator, Wind Turbine on 28 December 2009
Wind generators can either be bought or made, the choice is yours. To date, the increasing consumption of electricity will lead to a depleted supply of fuel and coal. Due to this, more and more people are now considering using wind generators. It is therefore not surprising that the wind generator sale is becoming more and more popular.
Since the prices of all commodities are also fast on the rise, people will want to get the best value for their money. This means if they think buying a second-hand wind generator is more cost efficient then they will choose a slightly used or used wind generator over a new one.
In the event that consumers have more money to spare and think that having a new wind generator will perform better and last longer than getting a second-hand machine, then they will choose to buy from a manufacturer or a wind generator reseller. The point is whichever will work best for a person remains a motivation on whether they will acquire a new machine or a second-hand generator.
Regardless whether you want a new or used generator, some aspects should be thought of such as the location, the presence of wind, government or housing association rules before acquiring a wind generator.
After you have reasonably complied with all of the considerations needed before installing and using a wind generator, only then will you become aware and enjoy the benefits of having a working wind power generator. The best advantage of installing and having a wind generator is saving money because you already have an alternate power source and using an environment friendly machine.
Posted in Wind Generator, Wind Turbine on 22 December 2009
The principle behind how a wind turbine generator works is its ability to change mechanical energy into electrical energy. This type of generator is not similar to the typical generating machines which are attached to an electrical source or grid. A turbine generator on the other hand, requires wind as its power source and this must work with the wind turbine rotor resulting in torque or mechanical power which is fluctuating by nature.
On big wind turbines, the voltage produced is around 700 V three-phase AC. This voltage either passes through a transformer located within the tower or beside the wind turbine to increase it to 10,000 up to 30,000 volts. This will still depend on the electrical grid used.
Most manufacturers will provide a 50 Hz wind turbine as well as 60 Hz type of turbine which are commonly used in America.
While working, generators will require cooling. Cooling is usually accomplished by placing the generator in a duct with the use of a big fan to produce the cooling effect. Meanwhile there are a few companies which make use of a water cooled generator. The size of a water cooled generator is compactly designed, increasing electrical efficiency.
This is not possible unless a radiator is placed in the nacelle to remove the heat from the generator through the liquid cooling process.
Every thing that is mentioned here are just the basics of how a standard turbine generator works. It may still vary depending on the design of the manufacturers.
Posted in Wind Turbine on 18 November 2009
Originally, the typical wind turbine technology was developed for industrial purposes and not for residential consumers who live in cities. However, there are new developments from researches conducted by the Hong Kong University and Motorwave Ltd., leading to the creation of the micro wind turbines.
The advantage of the micro wind turbine over the conventional wind turbine is its size. Moreover, this special wind turbine is light as well as compact with a rotor diameter of only 25 cm, not to mention its capacity to generate power even with very low wind speeds like 3 meters/second. This also means you can use a micro wind turbine in the privacy of your environment regardless whether you live in rural or urban areas.
There are tests that show turbines which are arranged within a square meter of surface area together with wind speed of 5 meters/second can produce about 130 kWh/year. In addition, the turbines can be connected to fit anywhere and one row of turbines is priced at only $150. This can even become lower once the gear-like turbines have been mass produced.
If you still want to know why you should choose micro wind turbines over its conventional counterpart? The answer is quite simple. It is because you want to save on your electricity consumption without too much trouble at a price that you can definitely afford. Of course, if you think that the power generated by micro wind turbines are not adequate, you can always purchase the typical wind turbine.