Solar-powered lighting systems rely solely on energy from the sun to produce light. For many consumers, these systems represent an upgrade in power source for lighting systems.
Advantages of Outdoor Solar Lighting
Although the initial costs of acquiring the components of a solar-powered system are higher than connections to standard electrical outlets, the costs of operating solar powered systems afford substantial cost-savings over extended periods of time. They also provide environmentally conscious consumers an attractive option as they reduce the need to rely on polluting fossil fuels.
Since these systems do not cost anything to operate, it is possible to use them in a variety of ways in addition to security. Solar powered lamps may be used to provide accent or highlight lighting of gardens and architectural features.
Components of an Outdoor Solar Light
A major advantage to solar-powered lighting is its ease of installation. Most solar-powered systems include a plastic case, solar cell, AA battery, control board, Light Emitting Diode (LED) light source, and a photo resister that detects darkness. They do not require external wiring since they do not rely on artificially provided power sources. They may be placed wherever they can receive light.
System components should be durable and weather-resistant. It is possible to utilize solar-powered lighting systems in a variety of climates and thus they may be subject to heavy rains, snow, and of course intense sun. An inexpensive system may not last as long as its owners expect, so a more substantial investment may be worthwhile.
Operation of a Outdoor Solar Lights
A standard system stores radiant energy from the sun during the day and releases it at night. The solar cell absorbs the energy and transfers it to the battery at a maximum of 0.45 volts. The amount of current that the cell transfers depends on the size of the cell and the quantity of light in contact with the surface of the cell.
Cells may be wired together in a series to produce more voltage. A diode provides a connection between the solar cell and the battery. It ensures that energy current flows in one direction from the cell to the battery instead of back to the cell. During daylight hours, the battery receives the current and stores it for usage during dark hours at a maximum of 700 miliamp-hours.
Of course, during winter time, when days are shorter the solar cell receives less energy, transferring less current to the battery. Overcast days also inhibit the cell's ability to absorb energy. When darkness falls, the solar cells stop receiving energy and the photo resister activates the LED drawing approximately 45 miliamps from the battery, at about 1.23 volts or 0.055 watts. The LED may be operated for 15 continuous hours. This current produces an amount of light equivalent to half that produced by a single candle.
Power and light output are regulated by the controller board. Newer models may use multiple LED's to produce more light and some models feature enhanced energy absorption and transfer, producing brighter light. Consumers should understand that the solar cell does not absorb all of the sun's energy to which it is exposed. Current estimates of the latest technology place absorption rates at about 15%. Although most experts concur that solar-powered light does not shine as brightly as others, the technology continues to advance.
Drawbacks of Using Solar Lights
As mentioned above, a single solar cell produces an amount of light equivalent to half that of a candle. This amount of light is insufficient to provide a genuine amount of light for the security conscious. Although the technology continues to progress, and many find usage of these systems for security measures adequate, at present they are still more of a decorative feature or may also provide adequate light to illuminate paths.