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Solar Photo voltaic lantern is basically a portable lighting device suitable for either indoor or outdoor lighting covering a full range of 360. The lantern can be used for 3 hrs/day with autonomy of 2 days.

Solar PV lantern consists of:

 • 7W CFL Lamp  • Sealed maintenance free Battery  • Electronics  • Solar PV Module  • Module mounting structure  •  Interconnecting cable

The battery, lamp and the electronics are placed inside portable ABS plastic housing.

Solar PV module generates electricity when exposed to direct sunlight, thus exploiting the unlimited source of free energy. A PV module consists of several small solar cells made of semiconductor material. Each of these solar cells generates a DC voltage and are capable of producing a finite amount of current. These solar cells are connected in series to form a PV module and are terminated to a terminal block for external connections.
 The System has been designed to meet the following requirements:

The PV module has to be mounted external to the building on rooftop with maximum exposure of solar cells to the sunlight. Mounting frame provided may be used for fixing the module in position.

Compact fluorescent lamps also known as CFL are energy saving and the most efficient lamps. Due to the nature of their construction, these lamps generate higher light (lumens) output for a given amount of power or in other words these lamps consume less amount of power when compared to other lamps for a given light output.

In the Solar lantern, Sealed lead acid maintenance free rechargeable batteries are used.

The complete electronics basically consists of two functions:

1. BATTERY CHARGE CONTROLLER to protect deep discharging and overcharging of the battery. Suitable circuits have been provided to continuously monitor the battery voltage and based on preset voltage levels prevent either over charging of the battery or deep discharging. Circuits for providing visual indication to indicate battery state of charge are also provided.

2. INVERTER to generate the recommended AC voltage to the CFL and to ensure proper ignition and subsequent glow of the lamp. The inverter converts DC battery voltage to AC, which is fed to the lamp. Suitable filtering circuits are provided to ensure as good a sine wave as possible across the lamp.