Solar Lanterns
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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.