Solar lighting    Home
Bookmark this page

Solar power

Hydroelectric power


Bookmark this page

Solar lighting is often used for solar garden lights, since lamps in the garden are exposed to sunlight throughout the day. Since a renewable energy source is used, electric power is saved, no electric wiring is required and  there is  no problem of electric shock from exposed cables during the rains. 

Solar lighting  usually consists of  solar cells , batteries, LEDs and associated electronic circuitry. Several solar cells are connected together to generate sufficient voltage and current to charge the batteries. The solar energy is usually stored in NiCad (Nickel Cadmium) or NimH (Nickel metal hydride) batteries during the day.

A diode in the solar lighting circuit prevents the current from the battery flowing through the solar cells at night. After exposure to more than 5 hours of  direct sunlight, the batteries of the solar light are fully charged and charger electronics prevents overcharging

At night, the photo resistor (photocell) in the solar lighting turns on the LED and the energy stored in the batteries is discharged at night. Unlike conventional batteries used in cars, the batteries used for solar lighting are deep discharge batteries and can withstand several cycles of  charging and discharging. The LEDs used in solar lighting consume very little power and the light output is similar to that of  candles.

Solar lighting is not widely used since monocrystalline silicon which is used for manufacturing photovoltaic (solar) cells is still expensive. The light output depends on location of  the solar cell and weather conditions. On a cloudy day, less energy is stored in the batteries. Also the LED light output is the maximum in the first few hours of  operation at night and gradually decreases. The battery used for solar lighting usually has to be replaced after a year, but the LED and solar cells work for several years.  

To advertise on this website and other websites in our network, check Text link ads or email / mail (at)