There has been a lot of work done to find ways to save energy, the creation of an electrical device that uses only a small amount of energy or the design of a system that helps to minimise power usage while still making use of current technologies.
In this post we will explain, a method of controlling the lighting in a single room; called as “light control system” (LCS) with the help of a control system, energy consumption may be reduced and user satisfaction increased.
The post includes the algorithm used in the Lighting Control System. The algorithm specifies that the system should first see whether someone is there.
In the condition, the system will detect how bright the room is and, if necessary, turn on the lights.The lighting system can effectively illuminate the room while using as little energy as needed.
Necessity of Efficient Light Control System
Power conservation has become an essential in everyday activities. Many conventional power-saving techniques, like using electrical equipment that uses very little energy or turning off the power entirely for a set period of time for a specific area, are ineffective and could cause significant discomfort for the users as well as increased costs.
Up to 40% of energy use occurs in buildings. The majority of this energy is mostly required to ensure suitable lighting for the employees.
Modern automated or modernised buildings may now feature lighting systems to increase occupant comfort and save energy. However, there are many older structures still using traditional lighting.
An intelligent and efficient strategy is explained in this post to lessen the energy consumption in various sorts of buildings and to assist the building owners in reducing their power cost. A relatively inexpensive and portable approach to assess our environment is now accessible because to advances in sensor technology.
Existing Lighting System
Whenever a lighting system turns on a light in a room that isn’t being used at that time, or whenever it does so even when there is sufficient illumination for the work at that point, it is possible that energy loss has occurred.
This can be determined by determining whether the light was actually needed for the work at that point.
The following is an overview of the many types of lighting systems that are used on a regular basis:
1). A manually operated switch
2). Through occupant detection
1). A manually operated switch
This method requires the user to turn on & off the necessary lights. There is a potential of leaving the lights on even when they were not needed since the user may turn the lights on and off according to their preferences.
This might happen as a result of the user’s negligence, resulting in the loss of a significant quantity of power.
2). Through occupant detection
This method initially determines whether the room is occupied. If an individual is present in the room, the light is checked to see whether there is adequate light before being turned on and based on motion, the light is turned on.
The passive infrared sensor (PIR) is used in the lighting system with occupancy detection. Any movement in that specific area is detected by this PIR sensor.
If there is any movement, this system automatically turns on the lights. The lights will remain on even after the user has left the area if timers are not employed in this type of configuration. This error may also waste a significant amount of energy.
Another disadvantage of this type of system is that it will turn on the lights when it senses movement in the room. However, there is a chance that there will be adequate illumination at that specific time.
Before turning on the lights, this system fails to monitor the light intensity. Moreover, a significant quantity of energy may be wasted as a result.
Effective Light Control System
All of the disadvantages of the existing system are resolved by the effective light control system.
Before initiating any measure, this system considers two factors:
- Presence of people, and
- Intensity of the light.
- A PIR sensor (Parallax555-28027) and
- A Light Dependant Resistors – LDR (NORP 12)
are included in the system.
The PIR sensor is used to determine if there are any inhabitants in the room, and the LDR is used to determine the level of lighting. In addition, an algorithm that employs both the LDR and PIR sensor to determine whether to turn on the light may be implemented in this system.
Function of Effective Light Control System
- PIC 16F877A,
- LDR,
- PIR sensor, and
- Relays
can be employed to create this system and control the lights.
The LDR sensor will continue to measure light intensity and transmit it to the microcontroller. If a person enters the room, the PIR sensor will send a signal to the microcontroller.
The microcontroller checks the intensity measured in the room with the value previously recorded in the microcontroller whether anybody is there.
The light will be turned on by connecting the relay if the measured value is less than the value already recorded in the microcontroller.
Algorithm of Effective Light Control System
Step-1: Start
Step-2: Using a PIR sensor to determine whether someone is in the room.
Step-3: Compare the amount of light in the room that the LDR measured with the presence of any occupants. If no one was there, go to step-1 again after a little pause.
Step-4: If the perceived (sensed) intensity is less than the needed level, turn on the light. If it was sufficient, go on to step-1 after a short time.
System will verify in accordance with the algorithm, whether there are any inhabitants in the room where it has been placed using a PIR sensor.
If there are any occupants, it will check the light luminance value sensed through the LDR and compare it to the value maintained in the microcontroller.
If the difference is greater than the value stored, the lights will be turned on, otherwise it will wait for a while before starting the process over.
If no one is present in the room while the system is looking for inhabitants, it will wait a delay that may be set into the microcontroller before proceeding to the initial step.
Flow Chart
Effective Light Control System Configuration Test
The Effective Light Control System has been tested in a room with 4 numbers of 40-watt lights. The intensity needed has been configured to 500 lux, which was established as the reference (starting) level in the microcontroller.
The daily energy use was approximately 800 watts prior to the implementation of this technology.
It has been significantly decreased to 480 Watts when this system was installed in that room. Thus, a significant amount of energy can be saved by using this system.
Application of Effective Light Control System
This system will help to maintain a productive working environment while reducing power usage to minimal levels.
This system allows for the inclusion of a person counter that counts the number of people in the room as well as wireless data transmission from the PIR sensor to the microcontroller, making it scalable in the sense that it can be used to control many different rooms.
In addition to these features, the system may be modified to enable real-time light intensity setting by users.
