Electronic Street Light Using Solar Power and LED

Transcription

1 Electronic Street Light Using Solar Power and LED Shruti lohiya, Vijay laxmi kalyani Shruti lohiya, pursuing B.TECH, IV SEM (EC Branch), Govt. Women Engineering College, Ajmer Vijay laxmi kalyani, Assistant Professor (EC department) Govt. Women Engineering College, Ajmer Abstract --- In this fast moving world with new scientific era electricity i.e. electrical energy plays a very vital role. New developments and new inventions are made which focus on saving this non-renewable electrical energy. Presently street lights mounted uses electrical energy along with compact fluorescent lamp which has very high electricity consumption. In this paper the author is making an effort on saving electricity by using solar power, LED, and sensors for street lightening. This present article talks about switching of street lights in the evening when there is dark using solar energy stored but focuses on switching only when any object/vehicle/public passes by, by using sensors and then is automatically switched off when they are passed, which shows a perfect example of energy saving. Keywords: LED, street lights, solar power, sensors-ldr and PIR I. INTRODUCTION Mainly what we are known about the solar energy is that it is the main source of sun energy and a good source of vitamin D. Also about LED that those small bulbs which require less operating voltage and produces desired output that is light energy. Sensors, by hearing this word for the first time the first meaning that comes in our mind is anything related to senses or sensing. But what about when all the above three components are patched up to produce a new technology in the scientific era. in the day time and lights up the led when it is in need in the night time. PIR sensor is also used which senses the activities and responds. Sensing is mainly done very creatively that is the street light will be automatically switched ON when any vehicle passes which will be detected/sensed by PIR sensor and light will be switched OFF when the vehicles are passed that is out of range of PIR sensor. The same process happens with human beings/passer by which saves a huge amount of electricity for the future generation. I.I. LED s: Light-emitting diodes (LED) are semiconductors. When electrons pass through this type of semiconductor, it turns into light. Compared to incandescent and CFL bulbs, LED lights are more efficient at turning energy into light. Therefore, less of the energy radiates from the bulb as heat. LED stands for light emitting diode which is also known as a semi-conductor device which converts electrical energy into light energy. Semi-conductor is extrinsic type semiconductor where impurities are added to form a p-n junction. The diode emits electrons, photons in the form of light energy when it is forward biased. Presently the street lights uses electricity to operate while in the day time also sometimes lights are left switched ON which wastes a good amount of electricity. New invention when implemented uses either solar energy with CFL s (used in street lights) or uses LED s operated using electricity replacing the CFL s and tube lights. In this paper author is focusing on using LED s powered with solar energy and a new idea of using mini sensors. LDR that is photo resistor is used which saves energy through solar Fig.-1 Light emitting diode Source: 9

2 1. Traditional inorganic LED S: as the name suggests it is manufactured from inorganic materials which usually comes in bicolor, multicolor LED s. Fig.-2. Showing Traditional Inorganic LEDs. Source: 1. Organic LED s or OLED: this type of LED uses organic materials for its manufacturing. Presently finding many rising applications from television set screens to computer monitors, Smartphone s to watches. Material as aluminium8hydroxyquinoline and diamine are often used. In the recent developing field OLED s are widely used due to its flexibility, colour capability-can produce a wide range of colours, power consumption is very less. Fig.-3. Showing OLED Active Matrix. Types of bulbs 1. Incandescent bulbs 2. CFL lights 3. LED Fig.-5. High Brightness LED. Table-1: Expected life time hours hours hours Main purpose which shows the advantages of using LED in street lights are: 1. Life time: as in above table no. 1 the life time of LED s are much more as compared to CFL S and incandescent bulbs which are presently used in street lights. 2. Power consumption: power consumption of led is very less which helps to save electricity. 3. Shock resistance: LED s are not damaged by external shock as high voltage power supply. 4. Switching time: LED s take very less time to switch ON or OFF. 5. Size: Sizes of LED s are very small so that they are easily mounted. 6. Eco friendly: unlike other lights led do not emit light energy or we can say heat energy which is very harmful to environment. I.II. SOLAR POWER/ENERGY: Conversion of sun energy known as sunlight into electrical energy known as electricity describes solar power[1]. This can be done either directly using photovoltaic (PV) or indirectly using concentrated solar power. Solar panels are mounted along with the object so that at the time of supplying energy, solar panels are used. In this paper we are using solar energy instead of electrical power supply which is a good alternative. Fig.-4. Showing Organic Light Emitting Diode Structure 2. High brightness LED s: these LED s area a type of inorganic LED s. As the name says it produces much greater output also have higher luminous intensity. When sun rays falls on solar panel it starts charging and the charge is stored and passed on to charge controller. The required amount of energy is supplied to battery and the rest is stored in charge controller itself. From battery energy is supplied to LED and thus it glows producing light.sunlight intensity varies according to day time also according to direction. So we can also mount or use mirrors at certain different angels and by using the concept of reflection we can increase the intensity of sunlight. 10

3 Cost of solar energy is falling rapidly and thus is a very good money saver and electric energy saver. Fig.-9 Showing Solar Powered Street Light Fig.-7. Showing Use of Solar Energy I.III. STREET LIGHTS: Light usually mounted on a pole and constituting equally spaced at intervals along a public street or highway. In this unsecured world where human beings are very unsafe at night on road without street lights which forms a major reason for road accidents and also there is a fear of thief so our homes are also unsecure and are unprotected. We are using solar panels mounted on street lights which glows up in the dark using LDR sensors and PIR sensors which will detect the vibrations and infrared light and thus a message passes to ON the street light when any vehicle or human being passes. LDR i.e. light dependent resistors which detect the darkness and then allows the street light to light up through solar energy. Fig.-10. Showing PIR Detection. I.IV. SENSORS: Sensors are sophisticated devices that are frequently used to detect and respond to electrical or optical signals. A sensor converts the physical parameters (for e.g. temperature, blood pressure, humidity, speed, etc) into a signal which can be measured electrically. 1. PIR SENSORS: An electronic sensor used for measuring the infrared light radiation emitted from object in its field of view is called as a PIR sensor or pyro electric sensor [2]. PIR detects the infrared radiations which are emitted by every object having temperature above absolute zero which are not visible to human eye. Fig.-8. Showing Street Light PIR sensor itself is split into two halves, which are sensitive to infrared radiations and whenever object comes in the field of view of the sensor, and then positive differential change will be produced. Between two halves with the interception of the first half of the PIR sensor similarly when the object leaves the field of view negative differential change will be produced. 11

4 Working with application: PIR sensors can be used for automatic street lightening whose operations are based on body or vehicle movement near the street light. [6] Fig.-13. Showing Basic Structure of LDR Fig.-10. Showing PIR sensors Fig.-14 Showing Typical Construction of Plastic Coated Photocell Fig.-11 Showing Detection Through PIR sensors 2. PHOTO RESISTOR- LDR: A photo resistor or LDR or photocell is a light controlled variable resistor which works on the principle of photoconductivity [3]. Photoconductivity is a phenomenon in which the materials conductivity is decreased when more amount of light is absorbed by the material. In the dark photo resistors have high resistance in the range of mega ohm (M Ω) while it have a low resistance in light nearly in ohms (around 100 Ω) These do not have p-n junction. If incident light on a photo resistor exceeds a certain frequency, photons absorbed by semi-conductor give bound electrons enough energy to jump into the conduction band. The resulting free electrons conduct electricity. When light having enough amount of energy is incident on the material more electrons jump into conduction band which increases the amount of charge carriers. Fig.-15 Showing Ilumination along with Resistance in different Day Light. I.V. TRANSISTORS: A transistor is under the category of semiconductor devices which is used to amplify and control electronic signals with electrical power. Transistors have three terminals so as to connect to our circuit. Transistor can act as amplifier and as switch as well. In this paper we are using transistors mounted near to LDR so that whenever we want to glow our LED message will be passed to transistor and switch will be in ON position which will allow LDR to work and thus our circuit will be completed which will result in current flow and thus LED will glow. 12

5 circuit comprising an operational amplifier, an electronic switch and an electromechanical switch. The circuit is switched ON or OFF by the transistor in saturation region or cut off region respectively, which is controlled by the signal from LDR. The collector current from the transistor toggles between ON or OFF modes [3]. Fig.-16 Curve between voltage and current 4. A Battery is an electric cell or a device that converts chemical energy into electricity. It consists of two or more cells connected in series or parallel. When this electricity is passed on to battery, battery starts charging up. We can compare the working with capacitor as when current flows capacitor starts charging up and when current is stopped it starts discharging. Same will happen in battery, in the day time when we are having ample amount of electricity this is passed on to battery and it starts charging up to its maximum range. After sunset battery will stop charging. 5. Now when any person will pass from there, firstly when coming nearer to street light it will come in range of PIR sensor. PIR sensor will detect the motion (in terms of heat produced by the body) and will send a message to micro controller to switch ON the led. This message is passed on to transistor and switch of the transistor will be in ON position. This switch will be connected to LDR which will pass message to LDR and thus the circuit will be completed which will result in glowing of led. Fig.-17 circuit diagram II. METHODOLOGY Sun Solar Panel Charge Controller Battery Transistor LDR LED 1. When sun rays will fall on solar panels, it will convert light energy into electricity (photo voltaic effect). Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Inphotovoltaicmany types of materials are used like monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride and copper indium gallium selenide [3]. 2. Solar module is a packaged, connected assembly of photovoltaic cells. The solar panel can be used as a component of larger photovoltaic system to generate the electricity and also supply electricity. A single solar panel can produce a limited amount of power so most installations contain multiple panels. In photovoltaic system arrays of solar panels are used, an inverter is made in series to achieve a desired output voltage and/or in parallel to provide a desired current capability. The conducting wires also used that take the current off the panels may contain silver, copper or other non-magnetic conductive transition metals. The cells are connected electrically to one another and to the rest of the system. 3. Now this electricity is passed to charge controller so as to adjust the varying amount of electricity. The charge controller serves as an interface between the current generated by the module and the battery charging during the day. The battery is prevented from over- charging by the charge controller. The charge controller is an electronic 6. When person will pass away from the street light he will be out from the range of PIR sensor and thus a message will be sent to micro controller to switch OFF LED, this will pass to transistor and it will be OFF and LED will not glimmer. The same process happens each time when any person/vehicle will passes through.[7] II.I. WORKING WITH CIRCUIT DIAGRAM Fig.-18 Circuit Diagram of Street Lights That Glow on Vehicle Movement, Source: The circuit consists of microcontroller, LDR, PIR sensor and RTC. This system controls the street lights using LDR and PIR sensor [4]. Street lights are switched on depending on the intensity of the Sun light on LDR. If the intensity of Sunlight on LDR is low, its resistance value is high. When it is completely in dark this value increases and then becomes high. This resistance value decides when the street lights are required to switch ON. The 13

6 resistance of LDR in dark is in ohms and in dark its resistance is in mega ohms. When the resistance value is maximum in midnights, real time clock (RTC) comes into the play. When there is no traffic the microcontroller checks peak time and switch OFF the lights. When there is any vehicle passes on the road, it is detected by the PIR sensor. Whenever PIR sensor is detected it just indicates the microcontroller to switch on the street lights. Then lights are switched on for 2 to 3minutes and then automatically switched off. LCD is also used for displaying time. Time from RTC is read and displayed on the LCD. III. APPLICATIONS a sensor to help in the automatic switching, PIR sensors can be used for automatic street lightening whose operations are based on body or vehicle movement near the street light. The equipment was fabricated along with a switching circuit which activates and deactivates the system as well as a charge controller unit that prevents the battery from overcharging. The system was also built to conserve energy with the use of a LED lamp to replace other lamps such as the fluorescent lamp which might reduce the efficiency of the battery. The power consumption of LED is very less which helps to save electricity. In the solar panel DC supply necessary to charge the battery without the need for a conversion to an AC so there is no need of inverter. V. FUTURE SCOPE: This idea plays a vital role in saving electricity for future generations and also minimizes the space used by a single component thus more and more components can be used in a single instrument to achieve more benefit. Electronic Street Light Using Solar Power and LED can be used in parking areas of industries, hotels, restaurants and highways etc. LED Bulbs/lamp is used, so maximum energy can be saved. It is very low cost and it has more life span. Fig.-19 Picture Showing Garden with LED Lighting Source: IV. CONCLUSION In this paper the street light system describes by using solar power, LED, and sensors. The street light system needs a charge controller to prevent the battery from damage and also REFERENCES [1] [2] [3] [4] Oke A. O., Adigun A. A., Fenwa O. D., Design and Construction of Solar Power-Based Lighting System, ISSN: , [Oke,2(9)September,2013].pp [5] [6] Archana M, mahalahshmi.r E-STREET : led powered intelligent street lightening system with automatic brightness adjustment based on climatic conditions and vehicle movements ISSN print : , vol 3, special issue 2, april 2014 [7] K C FOO, S karunanithi, G thio performance of new generation pole light 4th international conference on energy and environment 2013(ICEE2013) earth and environmental science 16(2013) Author s Details: First author: SHRUTI LOHIYA, presently perusing B.TECH IV sem from EC branch from govt. women engineering college, Ajmer Second author: V.L KALYANI assistant professor in ECE department Govt. Women Engineering College ajmer, IAENG membership. Attended various seminars and conferences, STC and FDP S etc. published many papers in Conferences and Journals. 14