Solar Home System (SHS)
Depending on the size, an SHS can operate one or several lights. Normally a SHS will have a 12-volt direct-current (DC) stand-alone system which uses PV to electrify small rural homes. Each SHS comes along with a PV module (also called Panel), a battery, a charge controller, wiring, LED lights, and outlets for other appliances. A typical design component is shown below:
It is important that those involved in choosing this system understand the different components. An elaboration of each of them is given below:
Module
Solar modules for an SHS would range between 20-50 Wp. They are mounted on a rooftop or atop a pole.
Battery
An electro-chemical storage battery is used to store the electricity converted by the solar module. During the day, electricity from the module charges the storage battery. During the evening, the battery is discharged to power the lights and other applications. Batteries are typically the 12-volt lead-acid batteries, ranging in capacity from 5-75 Amp-Hours (Ah). Batteries are typically sized to provide several days of electricity or 'autonomy', in the event of overcast weather preventing recharging.
Charge controller
A charge controller is utilized to control the flow of electricity between the module, the battery and the loads. It prevents battery damage by ensuring that the battery is operating within its normal charge levels. If the charge level in the battery falls below a certain level, a 'low voltage disconnect' (LVD) will cut the current to the loads, to prevent further discharge. Likewise, it will also cut the current from the module in case of overcharging.In rural areas, where literacy levels are relatively lower, The presence of this device with technical protections help prevent overuse of the battery, thereby increasing the life of the system.
Lights
Led based light bulbs and other fixtures are used for lighting. An SHS normally would have anything between two-light systems to a four-light system.These Led lights have a 5-year lifetime.
Wiring & Mounting devices
An SHS will also have additional materials for mounting and connections. Metal frames are included to attach the PV Modules to a pole or roof. The SHS components are connected by wires and contain switches for the lights. In some cases, wiring is housed inside conduits attached to interior walls. These are important considerations as damages to wires by rats in rural areas can considerably reduce the life of the system. Similarly, the high velocity of the desert wind can destabilize the PV modules if not clamped well on the roofs.
Benefits of the Solar Home Light system
The benefits derived from the use of solar lamps have improved the overall wellbeing of the households. This has been observed during interaction with the users at the field locations. Some of the benefits are listed below:
1. A leap towards children's education: Most parents met during the field visits mentioned that the reading habit of the children had increased. They study during the evening hours. This is especially true for those villages which have regular teachers at the village school.
2. Improvement in health: With the solar systems in place, fewer women will tend to suffer from respiratory problems. Kerosene fumes will cease to affect the eyes of the family members. Winters being cold, the houses are kept shut all the time, and the kerosene lamp emits so much carbon that not only do the eyes burn, but also respiratory problems develop. Women are affected much more severely than men since they stay at home for much longer hours. The summer season is prone to gusty storms which can result in fire. Houses getting gutted during summers are a common phenomenon. With the solar system in place, these two ills have been taken care of to an extent.
3. Saving of money: In several houses, the supply of kerosene, which is normally 3-5 litres a month, comes from the ration shop. This consumption can be reduced/stopped.
4. The other monetary benefit is the saving of money spent on charging themobile. It is also handy to charge the same from solar light when needed, rather than banking on someone going to the main market about 15-20 km away for charging it.
Features
|
• Very high efficiency electronic circuit
• Protects from overcharging and deep discharge of battery.
• LED indication for battery charging and battery low.
• Very low no–load current. (Option to Turn Off)
• Easy to Install (Plug and Use models, no help required)
• High reliability and durability.
• Excellent for remote villages as well as semi-urban areas.
• Protection: Reverse flow, over voltage, under voltage, reverse polarity, short circuit.
• Easy to Use and Operate.
|