Wind Turbine Tower

Turbines are mounted on towers because wind speeds increase with height in flat terrain. Generally speaking, the higher the tower, the more power the wind system can produce. Air turbulence can exist closer to the ground and the tower raises the turbine above it. It is a good idea to install a wind turbine on a tower with the bottom of the rotor blades at least 30 feet above any obstacle that is within 300 feet of the tower. By investing relatively small sums on in increase in tower height you can yield very high rates of return in power production. For instance, you can raise a 10-kW generator from a 60-foot tower height to a 100-foot tower with a 10% increase in overall system cost, but it can produce 25% more power. There are two basic types of towers: self-supporting or free standing and tethered. Most home wind power systems use a tethered tower which are the least expensive option. They consist of a simple, inexpensive framework of metal strips supported by cables and earth anchors. However, because the cable radius must be one-half to three-quarters of the tower height, cabled towers require enough space to accommodate them. Cabled towers can be hinged at the base so that they can be lowered to the ground for maintenance and repairs, or during hazardous weather such as heavy storms. Self-supporting or lattice-work towers are a sturdy alternative though the initial cost will be greater. Towers built with aluminum don't hold up to heat and cold conditions as well and should be avoided.

The Components of a Turbine: Horizontal turbine components include: * The Blade or rotor which converts the wind energy by rotating a shaft * A drive train which usually includes a gearbox and a generator * A tall post or tower that supports the rotor and drive train * electrical connections and home control interface

Types of Wind Energy Systems

Small wind energy systems may be used in conjunction with standard power transmission or grid-connected system or in stand-alone applications which aren't connected to the grid. A grid-connected wind turbine can significantly lessen your consumption of conventional electrical power used for your home appliances. If your wind turbine system doesn’t supply enough energy the conventional electricity makes up for it. However if your home wind power system generates more electrical power than what is required in your households, the excess may be sold to the utility. Modern electronics provide an automatic switching solution for sustaining a power supply either from the grid or you stand alone wind turbine. Stand-alone wind power systems are usable in households, farm, and even an entire community that is located in a remote area.

Wind Resource Measurement System

You should always do the necessary research to understand the available energy from the site location of the turbine. Direct monitoring with the use of a wind resource measurement system at the site you have chosen makes it possible for you to get the clearest picture of the available resource. You can use your own wind measurement system or hire a wind energy professional to take the measurements which may cost you between $600 and $1,200. You should set your measuring equipment high enough to avoid turbulence from the trees, buildings, and other hindrances. The most useful measurements are the ones that are taken at hub-height, the elevation at the top of the tower in which the wind turbine is actually installed.

Wind Energy Availability

Many parts of the United States have abundant wind resources. Wind energy is characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). An average annual wind speed of at least 13 miles per hour is considered a good wind resource and can be found in many locations.

A Brief History of Wind Turbines

The wind has been a significant energy source in America in rural areas and has played a great part in the settlement of the west. The mechanical windmill was deemed one of the two "high-technology" creations (one of which was barbed wire) of the late 1800's and paved the way for the development of the western frontier. More than 8 million mechanical windmills were installed in America beginning in the 1860's and some of them are still in operation today. Back in the 1920's and 1930's, families who lived in farms in the Midwest area utilized wind generators rated at 200-3000 watts for powering up their lights, devices like radios, and certain kitchen appliances.

Wind energy regained popularity around the late 70's and early 80’s because of the so called energy crisis at that time. As people began to search for different sources of renewable energy alternatives, small wind turbines came into the picture and were considered to be a cost-efficient means in dealing with such crisis. Tax credits and favorable federal regulations allowed for the installation of more than 4,500 small, 1-25 kW, utility-intertied wind systems at households between 1967 and 1985. An additional 1000 systems were put up for different remote applications.

Small wind turbines have been installed in all of the fifty States. After the expiration of federal tax credit in 1985 and following the oil price drop to $10 per barrel two months later, most of the small wind turbine industry were not able to stay in business. The companies that continue to produce wind systems are considered to be reputable and good providers of products. New companies and designs are entering the market as the price of oil and gas continue to rise.

What Is Wind Energy?

Wind is a form of solar energy and is caused by the heating of the atmosphere by the sun. The wind flows across the surface of the earth and the patterns vary with passage of wind through the earth's terrain. Mountain chains, oceans, lakes and vegetative masses affect the flow patterns of wind and this wind flow, when captured by modern wind turbines, can be used to generate electricity.

A wind energy system produces electrical current by means of gathering up the power from wind with the help of machines known as wind turbines. Wind energy may be generated for home use in stand-alone applications or by the use of multiple turbines called wind farms and distributed to the electric grid.

A typical wind turbine needs to have a sustained wind speed of a minimum of 10 miles/hour in order to turn the wind turbines fast enough to produce electrical current. Wind turbines typically generate around 50-300 kilowatts of electrical current depending on the location and size of the wind power unit.

Solar Power for Remote Locations

Solar cells are very useful places where there are no reliable established power grids. Solar power is popular in marine and recreational vehicle applications and is widely used for rural properties in remote locations. Independent energy sources such as solar provide a much needed alternative to a politically and environmentally unstable energy environment that we see on a regular basis. The earthquake in Japan did much damage to a nuclear power plant and this type of disaster underlines the need for more manageable sources of energy. Many people are beginning to embrace ideas of energy alternatives and solar power can provide a much needed substitute for total grid tied reliance.

Solar is Environmentally Friendly

Solar energy is a renewable fuel source that is environmentally friendly. Users of solar energy produce no emissions, noise or smelly by-products that disrupt the global village. There are no carbon emissions and the clean method of producing energy helps to eliminate the need to dig up, transport and burn fossil fuels. We're seeing that most systems established in the 60's and 70's are still functional. It is now believed that solar energy systems will last 40 or more years and manufacturers aren't afraid to back them up with 20 to 25 year warranties.

Some Advantages of Solar Energy

The fuel to power solar devices is sunshine and it’s free since our governments have yet to figure out a way to tax sunshine. The sun shines every day and will always be there. It is the most abundant source of energy available in the world and spills enough energy on the earth in 40 minutes to power every home on the globe. Little to no maintenance is required to keep a solar powered system functional. If you have a grid tied system then you don’t need a battery bank as a backup. Maintaining batteries is the biggest maintenance issue so if you use a hybrid system in tandem with a grid system you will have little maintenance. If you do have an off grid residential solar power system it is completely independent of the conventional power grid and will not be affected by grid power outages or rolling brownouts.

Cost and Expected Life Span of Solar Panels

Based upon prices these days, a typical single solar panel, with a rating of 100 watts, costs between $400 to $500, depending on its brand. However, the brand isn’t the only factor to be considered. When your system utilizes a large number of panels it is likely to be extremely costly. Nevertheless, modern solar panels generally have a life expectancy of 30 years or more. Keep this when deciding to add a solar system to your home knowing that you eventually will be using electricity free of charge.

Temperature and Wind Loading Considerations

If you have gone over the previous blog posts, you probably have learned that you should place solar panels in a sunny and non-shaded location in order to get the optimal amount of sunlight possible. However, build-up of heat can be an issue. Since the effectiveness of solar panels diminished as temperature increases, the solar panel mounting system must accommodate spacing within the individual solar panels to allow good circulation of air. The concept is to pave way for air cooling under the scorching sun in order to lower the solar panels’ temperature. Another factor to take into consideration is wind loading. When you let air flow around the solar panels, they will not only stay cooler, but there will also be less wind resistance of the whole array.

Tracking Solar Panel Mounts

They are designed to track the course of the sun during the day in order to optimize the solar radiation which the solar panels end up getting. A single axis tracker will track the sun’s rays east to west and a two-axis tracker tracks the day-to-day east to west motion of the sun as well as the seasonal declination motion of the sun. Tracking solar mounts are said to be the most effective type there is. Nevertheless, when you compare the difference in costs you might see that for the 20 to 30 percent gain in terms of output these mounting systems may give you, you could purchase 25% more panels and still get the same exact boost in electricity without mechanical failures to be worried about. Instead of spending 2 to 3 thousand dollars on a tracking system you could add two extra panels at $700 to $800 to compensate for the lack of direct sunlight. During the winter you won't have to worry about the mounting system freezing up.

Adjustable Solar Panel Mounts

The angle of inclination of any adjustable solar panel mount may actually be altered two or more times within a year in order to make up for the winter sun’s lower angle whilst the earth orbits the sun leading to change in season. An effective principle is latitude + 15 degrees during winter and latitude - 15 degrees during summer. This tends to boost the total solar panel output by around 25 percent. A hassle-free technique which actually works is to set the angle of inclination for the winter position during around mid-October and have it set back to summer position in mid-March.

Fixed Solar Panel Mounts

If you happen to be using probably the simplest and cheapest type of solar panel mounting system it’s likely to be totally stationary. It would be best to have the solar panels face the equator which is due south in the northern hemisphere. When using a compass to determine south keep in mind that true south is different from magnetic south. To give an example, true south in California would be 161 on a compass rather than 180. The actual angle of inclination in degrees needs to be set to your own latitude. A little more than your own latitude would certainly benefit the winter sun and a little less would benefit the summer sun.