Energy Conservation by Energy Audit And Use of Energy Efficient Lamps

Shekhappa G. Ankaliki *  Geetha M.M**.  Divyabharati K. ***  Bhagyashri P.M. ****  Jivita K. *****
* Professor, Department of Electrical and Electronics Engineering, SDM College of Engineering & Technology, Dharwad, Karnataka, India.
**-***** UG Scholar, Department of Electrical and Electronics Engineering, SDM College of Engineering & Technology, Karnataka, India.

Abstract

This paper presents energy conservation by energy audit and use of energy efficient lamps. In order to conserve energy and reduce electricity charges, energy audit is done for lighting system used in educational buildings and domestic applications. After comparison of energy efficiency, illumination level and cost of different bulbs, LED (Light Emitting Diode) bulbs are suggested to conserve energy, enhance energy efficiency, and reduce electricity charges. In order to demonstrate the proposed approach, different case studies are considered for energy audit and conservation of energy for the sustainable future. Finally economic analysis of energy saving and investment on LED bulbs and payback period is determined.

Keywords :

Introduction

In recent years, both electric utilities and customers have experienced increasing costs for electric energy. This is due to escalating costs for fuels that are used to generate electricity as well as the large capital costs for building the new generation units. Addition of new industrial units and population growth are further influencing the power crisis. Careful utilization of available energy will help operational engineers to minimize the power cuts. In this direction, the Energy Audit (EA) will help to understand more about the ways energy is used in any institution/industry and help engineers in identifying the area where waste can occur and scope for improvement [4]. Energy is the capacity of a physical system to perform work. Energy exists in several forms, such as heat, kinetic or mechanical energy, light, potential energy, electrical or other forms. Energy management is defined as the strategy of adjusting and optimizing energy, using systems and procedures so as to reduce energy requirements per unit of output while holding constant or reducing total cost of producing output from these systems [3]. Recently, the concept of energy audit and load management has emerged and it is being applied throughout the world [8]. Energy audit is the verification monitoring and analysis of the use of energy including submission of technical report containing recommendations for improving energy efficiency with cost benefit analysis and an action plan to reduce energy consumption.

A home energy audit and management is a service where the energy efficiency of domestic and commercial buildings is evaluated by a person using professional equipments with the aim to suggest the best ways to improve the efficiency in lighting and costing. An energy audit of a building involves various characteristics of building envelope, including roofs, walls, ceiling, and sky lights. The audit may also assess the efficiency, physical condition, durability of the lamps including conditioning equipments. Some of the greatest effects on energy use are user behaviour, climate, and durability of the lamps. The energy audit and management may therefore include energy billing history from the local utility and is often used to identify cost effective and energy efficient ways to improve the comfort and efficiency of the lamps. In [7], Energy Management and Conservation Strategies are discussed. The advantage of LED lighting for street lighting has been discussed in [5]. Importance of energy conservation, energy management and their opportunities is discussed in [1]. ISO 50001 for Efficient Energy Management System in industries is discussed in [6]. The energy management handbook has been realeased for official reference [2].

1. Objectives

The main objectives of this work is to,

2. Types of Lamps

The types of lamps available are listed below.

2.1 Incandescent Lamp

When an object is made hot, the atoms inside the object become thermally excited. If the object is not melting the outer orbit electrons of the atoms jump to higher energy level due to the supplied energy. If the electrons on these higher energy levels are not stable, they again fall back to lower energy levels. During falling from higher to lower energy levels, the electrons release their extra energy in form of photons. These photons are then emitted from the surface of the object in the form of electromagnetic radiation. This radiation will have different wavelengths. A portion of the wavelength is in the visible range, and a significant portion of wavelength are in inferred range. The electromagnetic wave with wavelengths within the range of inferred is heat energy and the electromagnetic wave with wavelengths within visible range is light energy. Incandescent means producing visible light by heating an object. An incandescent lamp works in the same principle.

The simplest form of the artificial source of light using electricity is an incandescent lamp. Here the electric current is flow through a thin and fine filament to produce visible light. The current rises in the temperature of the filament to such extent, that it becomes luminous.

Figure 1 represents different parts of the incandescent lamp. The resistance of the lighting filament conductor changing with temperature means that this incandescent lamp will have non-linear current-voltage curve characteristic. Voltage and current do not follow the simple equation "I=E/R" (with R assumed to be equal to 3 Ω) because an incandescent lamp's filament resistance does not remain stable for different currents.

Figure 1. Incandescent Lamp

2.2 Fluorescent Lamp

When the switch is ON, full voltage will come across the tubelight through ballast and fluorescent lamp starter. No discharge happens initially, i.e. no lumen output from the lamp. At that full voltage, first the glow discharge is established in the starter. This is because the electrode’s gap in the neon bulb of starter is much lesser than that inside the fluorescent lamp. Then gas inside the starter gets ionized due to this full voltage and heats the bimetallic strip that is caused to be bent to connect to the fixed contact. Current starts flowing through the starter. Although the ionization potential of the neon is little bit more than that of the argon, but still due to small electrode gap high voltage gradient is appeared in the neon bulb and hence glow discharge is started in starter. As voltage gets reduced due to the current causes a voltage drop across the inductor, the strip cools and breaks away from the fixed contact. At that moment a large L di/dt voltage surge comes across the inductor at the time of breaking. This high valued surge comes across the tubelight electrodes and strike penning mixture (mixture argon gas and mercury vapour). Gas discharge process continues and current gets path to flow through the tubelight gas only due to low resistance as compared to resistance of starter. The discharge of mercury atoms produces ultraviolet radiation which in turn excites the phosphor powder coating to radiate visible light. Starter gets inactive during operation of tubelight. Figure 2 represents fluorescent lamp.

Figure 2. Fluorescent Lamp

2.2.1 Advantages of Fluorescent Lamps

2.2.2 Disadvantages of Fluorescent Lamps

2.2.3 Applications of Fluorescent Lamps

It is used in domestic and commercial purposes, such as houses, apartments, shops, and schools.

It is used in domestic and commercial purposes, such as houses, apartments, shops, and schools.

The principle of operation remains the same as in other fluorescent lighting electrons that are bound to mercury atoms are excited to states where they will radiate ultraviolet light as they return to a lower energy level. This emitted ultraviolet light is converted into visible light as it strikes the fluorescent.

CFLs produce light differently than incandescent bulbs. In a CFL, an electric current is driven through a tube containing argon and a small amount of mercury vapour. This generates invisible ultraviolet light that excites a fluorescent coating (called phosphor) inside the tube, which then emits visible light.

It converts electrical energy to radiant energy. They are energy efficient and use better technology as compared to conventional tubelights and bulbs. It has two components,