Solar and Wind Power Defined

Their implementation is both environmentally and economically beneficial. They do not produce pollutants or greenhouse gases. Nor do they leak any type of contaminates.

They can reduce pressure on the commercial hydro grid, create employment and even revenue for landowners, such as farmers. Solar panels produce free electricity.

The following is a basic explanation of how each works as a source of electricity for home or business.

A photovoltaic cell, also referred to as a solar cell, is composed of a thin round or square semi-conductive material such as silicon. A thin film of semi-conductive material is used in some designs.

The material is specially treated to form an electric field. It is positive on one side and negative on the other. Conductors are attached to either side to form an electrical circuit. When sunlight strikes the solar cell, electrons are loosened from the material. The electrons are caught in the circuit creating an electrical current.

Researchers are also experimenting with special plastics that will be more efficient at turning sunlight into electricity.

When a number of solar cells are wired to each other and mounted in a support frame, it is referred to as a module. The current it produces is directly related to the amount of sunlight that hits it. Modules are developed to produce electricity at a certain voltage. For example, a 12-volt system.

When many modules are wired together, the arrangement is referred to as an array. They form a large solar panel. It is the type that is commonly seen on the roof of homes or cottages. The larger the array the more electricity produced.

Module and array systems produce direct current electricity (DC). The electrical is stored in a powerful battery. The direct current (DC) is then transformed to alternating current (AC) through a device called an inverter.

This type of solar energy is considered a good source of electricity for powering items such as lighting, telecommunications, microwaves, power tools, vacuum cleaners, radios, fans, televisions, computers and other electronic devices.

Currently in Canada, switching from the local hydro utility system to setting up a solar powered system is still expensive. The price paid for electricity from the local utility is still cheap as compared to other countries. However, as the price of electricity continues to rise, the cost for solar will continue to become an affordable alternative.

On the other hand, for a location in a rural or remote area where access to a hydro grid is not feasible or expensive to install, solar energy is a feasible alternative.

Portable Solar Power

Solar electric generators are also now available. They are an excellent alternative to the noisy gas or diesel ones.

Solar generators use solar panels (photovoltaics) to charge deep cycle batteries. A device referred to as an inverter transforms the direct current (DC) to an alternating current (AC).

The generators range in size from small and light to large and heavy. Smaller units are ideal for anyone working off the electrical grid system or anyone that requires a generator as a back up system. Larger, heavier units are ideal for construction or any type of commercial work in remote areas.

Solar electric generators are quiet, smokeless and non-polluting. The source (sunlight) and electricity generated are both free.
Information on portable solar powered generators is available at:

Solar Sense
www.solarsense.com

The turbine is the unit located at the top of a high steel or concrete tower.
The towers are high in order to capture strong wind speeds.

The most efficient for generating electricity is a horizontal axis turbine. It is a stationary unit that is fastened to the top of the tower. Typically there are three blades attached to a rotor (a part that revolves in the stationary unit). There is a weather vain, a device to keep the blades facing the right direction and an anemometer to collect wind speed data.

There are also many internal components. There are shafts, gears and a brake. There is a controller unit that can shut the turbine off when air currents are too strong. In many cases, turbines are computer controlled.

A very simple explanation of the process to produce electricity is as follows. The wind causes the blades to turn. The rotor turns with the blades and at the same time turns a low-speed shaft. This shaft is connected with gears to a high-speed shaft. This increases the rotations per minute. The high-speed shaft is connected to a generator. The generator converts the kinetic energy (energy created by motion) of the gears into electrical energy. The higher the rotations per minute, the more electricity produced.

Electric generators characteristically produce (AC) power. Some turbines generate a current frequency that is inconsistent. In those cases the current is converted to a direct current (DC) and then back again to an alternating current (AC). This is done in order to match electrical line frequencies and voltage for connection to electrical grids.

A wind turbine is large and the tower that supports it is high. The diameter (blade tip to blade tip) will range any where from 150 to 280 feet. (approx. 45 to 90 meters) depending on the design. The tower height will range anywhere from 160 to 320 feet (approx. 50 to 100 meters). The height depends on the size of the wind turbine.

Further information on solar, wind and Canada, is listed at the bottom of the page on electricity.
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Solar, Wind, Electricity