Put simply; solar powered lights work by converting energy from the Sun into electricity, enabling the lights to work. The clever bit is that the electricity can be stored within the system so that you can even use the lights at night.
Solar devices use solar cells to convert the suns energy into electricity. The cells are usually combined together into solar panels; the size of these panels can influence the amount of electricity that is produced. The first solar cells were reliant on being in almost direct sun light to function, however the technology has developed and there are now cells which can convert almost any light source into electricity. This makes positioning of lights and their power source much easier.
Storing the Electricity
The simplest storage is provided by rechargeable batteries (also known as accumulators). The volume of electricity that can be stored is directly related to the number of and the size of the batteries. The system charges the batteries during day time which is then available for use when required.
Controlling the Lights
The lights are controlled or switched on and off by use of a switch, this enables the power to be built up during the daytime with limited power drain. Although some products will allow the light to be manually switched on or off, some form of automatic switch is useful. One method of doing this is to use a photo resistor in the switch. The way that the photo resistor is used is to turn on the power when there is not enough light absorbed by it. So after building up the electricity during the day the system powers up the lights once it gets dark. Additional ways of controlling the light can be included for special types of lights; e.g. security lighting, which will be covered in another article.
Bulb, Fluorescent, or LED?
The humble light bulb, whilst a wonderful invention, along with fluorescent lamps; now have competition which includes LEDs'. An LED (light emitting diode) has many advantages, including much lower energy consumption and greater life. Whilst LEDs' have been around since the 1960s' it is only fairly recently that they have become useable for general lighting. The efficiency of today's' LED means that it can now emit a lot of light for relatively low energy input. This allows our solar powered lighting to work for several hours on the energy built up during the daytime. LEDs' are also available in a number of colours.
Solar power can enable us to light our properties for utility, security or decoration without using mains power. This could have considerable benefits to both the ecology and our pockets. Imagine what you could do with solar powered lighting around your own home.
DIY Solar Panels and Windmills Building Guides
Earth 4 Energy - Make your own solar panels or wind turbine. More info here
Home Made Power Plant - There are some other guides for DIY wind and solar generators, but all of those that I've read don't get into the same details. More info here