06-06-2010, 11:06 AM
[attachment=3687]
Project report
ON
SOLAR BASED L.E.D LIGHTING SCHEME
BY
ELECTRICAL DEPARTMENT BOOTH
TEAM MEMBERS
01. Arundhati Kalane (coordinator)
02. Arvind Shinde
03. Ashish Shahare
04. Bablu Jha
03. Gayatri Shirure
08. Jayshree Gawai
07. Monali Chaudhari
08. Parvez Naikwadi
09. Prasad Chitare
10. Priyanka Gugale
11. Ravindra Yadav
12. Rohita Sagavkar
13. Rugved Deshpande
14. Sagar Shelke
15. Sagar Zaparde
16. Sapana Yawalkar
17. Sharmily Mergu
18. Vishwabharati Ramteke
COLLEGE OF ENGINEERING,PUNE
TECHNOCRAFT EVENT
(ORGANISED BY:ALUMNI ASSOCIATION OF COEP)
Table of contents
1. Introduction
2. Light Emitting Diode
3. Project Management
4. Working Model
5. Load Calculations
6. Possible Modifications
Introduction
For the very first time a fully funded technical event has been organized by the Alumni Association of COEP .This event has created a great platform for the budding engineers to come forward with their own ideas and implement them practically. Seeing that conservation has become the need of the hour, the central theme selected for inaugural year of Technocraft is:-˜I CONSERVE FOR A BETTER TOMORROW ˜.
Under this theme, we have worked out on the topic ËœSolar Based LED Lighting Schemeâ„¢.
About The Topic¦¦
In the past decade the energy needs have raised globally .The world in general and India in particular has been facing acute shortage of electricity.
Solar Energy has long been the Holy Grail of the Non-Conventional energy sources. Many stupendous efforts have been exerted in an attempt to harness this free & simple form of energy for common man .This energy can be used as an alternative for electrical energy. The basic and major obstacle has been the huge infrastructure cost required initially.
Efforts are being made for many years to reduce the huge initial cost ,although the initial cost reduction seems to be a big challenge .However the benefits offered by its usage are so alluring that we can ,with no harm, neglect the disadvantage. We have designed and conceptualized our project model taking into consideration the lighting loads of the big educational institutes, which seems to be quite higher.
Solar energy driven equipments being less efficient, use of solar energy for conventional lighting scheme is hardly of any use. So to find an alternative to the conventional lighting scheme we thought of replacing it by LED lighting scheme. Thus we hope this will be a small but important step in helping increase the use of non-conventional energy worldwide &also to protect the environment, reduce the load on conventionally generated electricity grid among many other envisioned advantages.
Light emitting diode
Why LED
LED is a light emitting semiconductor diode that emits light. LEDs are most often used in the form of an indicator light in electronic devices, traffic signal lights, musical instruments and dashboards in cars and in houses etc. The nature of the light emitted can be visible, infrared or ultraviolet.
LED bulbs facts - What is an LED light bulb
LED light bulbs are made by arranging identical light emitting diodes closely to form the shape of a light bulb. The visible light thus produced closely resembles day light and is very capable of replacing the traditional light bulbs such as incandescent light bulbs and compact fluorescent lamps.
Lifespan of a LED light bulb:-
Most modern LEDs are undergo superior design and manufacturing process that gives them up to 100,000 hours of lifespan
Advantages---
¢ Power savings by using LED
Traditional incandescent light bulbs waste up to 80% of its energy in the form of heat that they produce. LED light bulbs on the other hand save that energy since heat emission is minimal. For example, you may replace a 40 watts standard light bulb with a 4 watt LED bulb that emits same light output.
¢ Benefits of using LED light bulbs over standard light bulbs
Power consumption of LED light bulb is only 10% of that of the standard light bulb.
LED light bulbs withstand great amount of vibration, shock and temperature variations.
LED Fast facts :-
¢ About LED light bulbs and incandescent light bulbs:-
1. Light bulbs are 10-60 times more energy efficient than incandescent light bulbs.
2. Incandescent light bulbs produce light that flickers whereas LED light bulbs produce flicker free light.
3. LED bulbs can produce many rich and vibrant colours when compared to incandescent light bulbs
4. According to the Clean Energy Act of 2007 incandescent bulbs that produce 310 - 2600 lumens of light are banned. This exempts light bulbs that use less than 40 watts or more than 150 watts of energy.
5. Survey says if the entire USA switches to LED bulbs, it can effectively reduce its power consumption by almost 30%.
Disadvantagesâ€
¢ Most modern LED operate in a range of 2 to 4 volts and consume anywhere between 350mA and 1500mA.
¢ The power consumption may sometimes vary from manufacturer to manufacturer and also because of the purpose for which the LED was designed.
¢ Another factor that affects power consumption of LEDs is for the fact that LEDs can not be dimmed.
¢ Lifespan of a LED bulb could dramatically come down due to the amount of heat a LED may produce. This directly depends on die temperature and ambient temperature of the LED. Most LED light bulbs show sign of age after a couple of years of use and may produce only 50% of the light output when compared to what it used to produce when it was new.
Project management
What we have done¦¦
As of now we have worked out this project model for the electrical dept. of college of engineering, Pune. . It revolves around the necessities of our department, envisaging a total freedom from tubes and incandescent bulbs in the near future.
This would prove to be a great step towards conservation of energy.
Our team consisted of 18 members, all from second year. We divided the team into four groups viz
1. The technical group
2. The design and construction group.
3. The survey and purchase group.
4. The finance group.
¢ Technical group:-
They designed the circuits, carried out testing under various conditions.
¢ Design and construction group :-
They designed and constructed the architectural structure of our model.
¢ Survey and purchase group :-
They carried out survey regarding lighting load of our department model, they also gathered all other necessary information concerning the project. They purchased the things required for the model.
¢ Finance group:-
They took care of the accounts.
Also the sequence of activities to complete the project in time and within budget was well planned beforehand.
Common meetings were held timely to check out whether everything was going on as per plan. Discussions regarding the challenges faced while working were solved during such meetings.
Working model
The working model focuses on the most commonly used areas in the department, which includes the classrooms, the lab and the corridors.
It is usually found that irrespective of whether or not there is need of light, all lights in the classroom are switched ON, which causes unnecessary wastage of power. To avoid this we have made use of the sensor circuits consisting LDRâ„¢s to detect the intensity of light available and turn ON only those lights that are necessary and switch OFF the unnecessary lights.
Further, a common tendency of students of not switching OFF the lights while leaving the classrooms leads to unnecessary wastage of power. To avoid this we have put on the counter circuit that counts the number of students entering and leaving the class. We have made use of two IR beams connected to the door, when students are entering inside the room they intercept the 1st ray first so signal is given to the first counter. Same thing happens while leaving the classroom with the 2nd ray intercepted first, and input going to the second counter. When count1=count2 i.e. the class is empty the signal is passed to the atomized control for switching OFF the lights.
[*ASSUMPTION:-only one person enters or leaves the class at a time]
The whole lighting control of single room is done with the help of only one switch. But, in case it happens that only one student wants to study in the class, then there is an additional arrangement of manual switches for individual bulbs for lighting only the required bulb.
We have also covered another aspect of passage lighting in our project which includes passage lighting with the help of timer circuit. We have designed the functionality of the circuit such that the passage lights start glowing at 6 pm but with low intensity. At 7 pm as it turns dark the intensity of lights is increase. Again at 8 pm when there is hardly anyone in the college, the lights turn dim. The intensity variation of lights is done by varying the voltage level across the bulbs.
The timer and the counter circuit have been done with the help of microcontroller.
¢ Microcontroller circuit
¢ Micro controller program:
Chip type : ATmega32L
Program type : Application
Clock frequency : 1.000000 MHz
Memory model : Small
External SRAM size : 0
Data Stack size : 512
*****************************************************/
#include <mega32.h>
#include <delay.h>
#define ADC_VREF_TYPE 0x20
// Read the 8 most significant bits
// of the AD conversion result
unsigned char read_adc(unsigned char adc_input)
{
ADMUX=adc_input | (ADC_VREF_TYPE & 0xff);
// Start the AD conversion
ADCSRA|=0x40;
// Wait for the AD conversion to complete
while ((ADCSRA & 0x10)==0);
ADCSRA|=0x10;
return ADCH;
}
// External Interrupt 0 service routine
interrupt [EXT_INT0] void ext_int0_isr(void)
{
OCR0=0x84;
TCCR0=0x1C; //timer on
delay_ms(60000);
TCCR0=0x00; //timer off
OCR0=0x200;
TCCR0=0x1C; //timer on
delay_ms(90000);
TCCR0=0x00; //timer off
OCR0=0x;
TCCR0=0x84; //timer on
delay_ms(120000);
TCCR0=0x00; //timer off
PORTB = 0xff;
delay_ms(1000);
}
// Declare your global variables here
void main(void)
{
// Declare your local variables here
unsigned char p,q;
int r=0;
// Input/Output Ports initialization
// Port A initialization
// Func7=In Func6=In Func5=In Func4=In Func3=In Func2=In Func1=In Func0=In
// State7=T State6=T State5=T State4=T State3=T State2=T State1=T State0=T
PORTA=0x00;
DDRA=0x00;
// Port B initialization
// Func7=Out Func6=Out Func5=Out Func4=Out Func3=Out Func2=Out Func1=Out Func0=Out
// State7=0 State6=0 State5=0 State4=0 State3=0 State2=0 State1=0 State0=0
PORTB=0x00;
DDRB=0xFF;
// Port C initialization
// Func7=Out Func6=Out Func5=Out Func4=Out Func3=Out Func2=Out Func1=Out Func0=Out
// State7=0 State6=0 State5=0 State4=0 State3=0 State2=0 State1=0 State0=0
PORTC=0x00;
DDRC=0xFF;
// Port D initialization
// Func7=In Func6=In Func5=In Func4=In Func3=In Func2=In Func1=In Func0=In
// State7=T State6=T State5=T State4=T State3=T State2=T State1=T State0=T
PORTD=0x00;
DDRD=0x00;
// Timer/Counter 0 initialization
// Clock source: System Clock
// Clock value: 3.906 kHz
// Mode: CTC top=OCR0
// OC0 output: Toggle on compare match
TCCR0=0x1C;
TCNT0=0x00;
OCR0=0x44;
// Timer/Counter 1 initialization
// Clock source: System Clock
// Clock value: Timer 1 Stopped
// Mode: Normal top=FFFFh
// OC1A output: Discon.
// OC1B output: Discon.
// Noise Canceler: Off
// Input Capture on Falling Edge
// Timer 1 Overflow Interrupt: Off
// Input Capture Interrupt: Off
// Compare A Match Interrupt: Off
// Compare B Match Interrupt: Off
TCCR1A=0x00;
TCCR1B=0x00;
TCNT1H=0x00;
TCNT1L=0x00;
ICR1H=0x00;
ICR1L=0x00;
OCR1AH=0x00;
OCR1AL=0x00;
OCR1BH=0x00;
OCR1BL=0x00;
// Timer/Counter 2 initialization
// Clock source: System Clock
// Clock value: Timer 2 Stopped
// Mode: Normal top=FFh
// OC2 output: Disconnected
ASSR=0x00;
TCCR2=0x00;
TCNT2=0x00;
OCR2=0x00;
// External Interrupt(s) initialization
// INT0: On
// INT0 Mode: Low level
// INT1: Off
// INT2: Off
GICR|=0x40;
MCUCR=0x00;
MCUCSR=0x00;
GIFR=0x40;
// Timer(s)/Counter(s) Interrupt(s) initialization
TIMSK=0x00;
// Analog Comparator initialization
// Analog Comparator: Off
// Analog Comparator Input Capture by Timer/Counter 1: Off
ACSR=0x80;
SFIOR=0x00;
// Global enable interrupts
#asm("sei")
// ADC initialization
// ADC Clock frequency: 500.000 kHz
// ADC Voltage Reference: AREF pin
// Only the 8 most significant bits of
// the AD conversion result are used
ADMUX=ADC_VREF_TYPE & 0xff;
ADCSRA=0x81;
while (1)
{
p = read_adc(0);
q = read_adc(1);
if (p<80)
{
delay_ms(2000);
if(q<80)
{
r= r+1;
}
}
if (q<80)
{
delay_ms(2000);
if(p<80)
{
r= r-1;
}
}
if(r==0)
{
PORTC = 0x00;
}
else if (r>0)
{
PORTC = 0xff;
}
};
}
¢ LDR Circuit:
¢ Counter circuit:
Load calculations
We have done the following calculations for single LED¦..
Supply voltage
(V) Current
(mA) Conditions
3.5 0.1 Just glows
5.16 1.5 Good intensity
13.6 5.3 Maximum intensity
15 7 Maximum intensity
26 11 Maximum intensity
The voltage drop across single LED is found to be 3.16 V
¢ Bulb specifications:
One bulb => 6 LEDs
Resistor value = 240 ohm
Supply voltage = 5 v
Current = 54 mA
Total no. of bulbs = 34
Total current = 1.836
Power rating = 9.18 W
Other circuitry load = 3 W approx.
Panel and battery ratings
¢ Panel ratings:-
1. Wattage = 10 W
2. Vmpp = 16.4 V
3. Impp = 0.6 A
4. Voc = 20 V
5. Isc = 0.63 A
¢ Battery ratings:-
1. Vo = 12 V
2. 7.6 A-h
3. Max charging current = 2.28 A
We also carried out survey for electrical department lighting load and found out that there are 230 tubes in use. These tube are of 40 W. But if they are operated using conventional chokes then they consume 10-15 W more i.e it becomes 55W for one tube. But as mentioned in our report earlier LED bulb of merely 4W can replace the tube of 40W providing same luminance. So present load requirement for electrical department being 9200W for lighting can be replaced by 920W just by using LED bulbs¦
Cost estimation
Sr. No. Items Quantity Amount(Rs)
1. MDF sheets 3 1500/-
2. Mount-board 16 400/-
3. Hardware (L-angles,nut bolts, screws,sandpaper,PVC pipes) 1555/-
4. Miscellaneous(thermocol,Papers,tape,fevicol,reflector material,ceramic,straws,sticks,colours and brushes) 1900/-
5. LEDs 700/-
6. Components 2400/-
Total -- 8455/-
Possible Modifications
¢ With the help of advanced techniques one can vary intensity of the bulbs smoothly so that they offer only the required amount of intensity and avoid unnecessary wattage loss.
¢ Solar Tracking Servo Mechanism, if applied will enhance the efficiency of the panel to a greater level.
¢ Good quality reflectors can be used in the bulb manufacturing which will provide more illumination.
¢ Using different kinds of reflectors the lights can be designed for variety of purpose.
¢ For e.g.: for reading we require focused light and for ambience sake we require dispersed light.
¢ Bulb casings can be made of some kind of environmentally degradable materials.
Innovative idea:-
An idea that ran through our minds while doing this project¦¦..
We pondered if ¦..at all we could design a device that will capture the intensity emitted by the bulbs and convert it into voltage which, if provided back to the charging circuit, will act as auxiliary charging source.
We found out information regarding such circuit which revealed that using photo diode such circuit is possible but it provides voltage of order of 10-6 which is practically of no use.
