08-02-2012, 04:13 PM
SOLAR LIGHTING SYSTEM
[attachment=17308]
INTRODUCTION
With increasing concerns about fossil fuel deficit, skyrocketing oil prices, global warming, and damage to environment and ecosystem, the promising incentives to develop alternative energy resources with high efficiency and low emission are of great importance. Among the renewable energy resources, the energy through the photovoltaic (PV) effect can be considered the most essential and prerequisite sustainable resource because of the ubiquity, abundance, and sustainability of solar radiant energy. Regardless of the intermittency of sunlight, solar energy is widely available and completely free of cost. Recently, photovoltaic array system is likely recognized and widely utilized to the forefront in electric power applications. It can generate direct current electricity without environmental impact and contamination when is exposed to solar radiation. Being a semiconductor device, the PV system is static, quite, and free of moving parts, and these make it have little operation and maintenance costs. Even though the PV system is posed to its high capital fabrication cost and low conversion efficiency, the skyrocketing oil prices make solar energy naturally viable energy supply with potentially long-term benefits.Solar lighting system is the use of natural light to provide illumination.
B. PHOTOVOLTAIC SYSTEMS
1) Photovoltaic cell
The p-n junction diode conducts when it is forward biased similarly the photo voltaic cell is like p-n junction diode by the incidence of photons it will conducts and produce voltage.
PV cell are basically semiconductor diode. This semiconductor diode has got a p-n junction which is exposed to light. When illuminated by sunlight it generates electric power. PV cell are made up of various semiconductor materials. But mono-crystalline silicon and poly-crystalline silicon are mainly used for commercial use.
PROBLEM IDENTIFICATION
The aim of is to demonstrate how we can utilise solar light to electrify the remote areas, i.e., how we can store the solar energy and then use it for small-scale lighting applications. Urban and rural lighting can be done by using solar energy. The advantages of using solar energy are the cost reduction of installation in the case of non availability of electric grid, reduction of electricity bill and contribution to the protection of the environments (Clean and renewable energy source).
The regulator: An automatic voltage regulator circuit is designed to be powered by a 12 AC supply. The designed circuit will fail to operate at a voltage below 12V. However, if the entire circuit draws up to 0.5A and voltage passing through it is about 12V, then the power dissipated by the regulator will be I(Vm-Vr)=0.512 82w,Where 8v is the regulated voltage. The regulator requires a heat sink to avoid it shutting down when operated for a long time.
The power supply: The 6v, 4.5AH battery used here is charged by means of the power supply of 6V using one 2200 micro(35V) capacitor, one IC 7808 regulator, one 12V 2000 ohms relay, twelve diodes, one kilo ohm resistor, two 100 ohms resistors, three light emitting diodes, 12-16v solar panel.
[attachment=17308]
INTRODUCTION
With increasing concerns about fossil fuel deficit, skyrocketing oil prices, global warming, and damage to environment and ecosystem, the promising incentives to develop alternative energy resources with high efficiency and low emission are of great importance. Among the renewable energy resources, the energy through the photovoltaic (PV) effect can be considered the most essential and prerequisite sustainable resource because of the ubiquity, abundance, and sustainability of solar radiant energy. Regardless of the intermittency of sunlight, solar energy is widely available and completely free of cost. Recently, photovoltaic array system is likely recognized and widely utilized to the forefront in electric power applications. It can generate direct current electricity without environmental impact and contamination when is exposed to solar radiation. Being a semiconductor device, the PV system is static, quite, and free of moving parts, and these make it have little operation and maintenance costs. Even though the PV system is posed to its high capital fabrication cost and low conversion efficiency, the skyrocketing oil prices make solar energy naturally viable energy supply with potentially long-term benefits.Solar lighting system is the use of natural light to provide illumination.
B. PHOTOVOLTAIC SYSTEMS
1) Photovoltaic cell
The p-n junction diode conducts when it is forward biased similarly the photo voltaic cell is like p-n junction diode by the incidence of photons it will conducts and produce voltage.
PV cell are basically semiconductor diode. This semiconductor diode has got a p-n junction which is exposed to light. When illuminated by sunlight it generates electric power. PV cell are made up of various semiconductor materials. But mono-crystalline silicon and poly-crystalline silicon are mainly used for commercial use.
PROBLEM IDENTIFICATION
The aim of is to demonstrate how we can utilise solar light to electrify the remote areas, i.e., how we can store the solar energy and then use it for small-scale lighting applications. Urban and rural lighting can be done by using solar energy. The advantages of using solar energy are the cost reduction of installation in the case of non availability of electric grid, reduction of electricity bill and contribution to the protection of the environments (Clean and renewable energy source).
The regulator: An automatic voltage regulator circuit is designed to be powered by a 12 AC supply. The designed circuit will fail to operate at a voltage below 12V. However, if the entire circuit draws up to 0.5A and voltage passing through it is about 12V, then the power dissipated by the regulator will be I(Vm-Vr)=0.512 82w,Where 8v is the regulated voltage. The regulator requires a heat sink to avoid it shutting down when operated for a long time.
The power supply: The 6v, 4.5AH battery used here is charged by means of the power supply of 6V using one 2200 micro(35V) capacitor, one IC 7808 regulator, one 12V 2000 ohms relay, twelve diodes, one kilo ohm resistor, two 100 ohms resistors, three light emitting diodes, 12-16v solar panel.
