Bab 13 lighting edit

LIGHTING

1. BACKGROUNDThe major objectives of energy audit in lighting system include:

Measurement and comparison of illumination levels at various

locations

Measurement of total power consumption of all lighting feeders

Calculate the installed load efficacy in terms of lux/watt/m²

(existing vs. design) for general lighting installation.

Compare calculated value with the norms for specific types of

interior installations for assessing improvement options.

To suggest ways and means to optimize the illumination levels and

to optimize the power consumption at different locations.

To identify energy saving measures and quantify the energy and

cost savings.

2. STEPS INVOLVED IN CONDUCTING THE ENERGY AUDIT

The steps involved in conducting energy audit of lighting plant are:

Data collection

Observations, measurement and Analysis

Exploration for energy conservation measures with detailed techno economic calculations

Report preparation

3. DATA COLLECTIONCollect the single line diagram of electrical drawing pertaining to lighting

Obtain the lighting fixture details for each section

Typical format for data collection of lighting details is given Table 13-1

Table 13-1

For illumination level required refer Annexure-13.1,where recommended illumination values as per IS: 3646 (Part-1) –1992 for various areas in power stations are provided.

If the plant has separate transformers for lighting circuit, provide the details of transformer

Details of energy saving retrofits installed in the plant (such as voltage controllers, sensors, controllers, timers, etc)

Details of on & off mechanism of lighting circuits

Details of energy meters provided in the lighting circuit and sections served by these meters

Details of energy consumption monitoring of lighting systems

Energy consumption of lighting circuit

4. INSTRUMENTS REQUIRED

The following instruments are required for conducting the energy audit of

lighting system :

Power Analyzer: Used for measuring electrical parameters such as kW, kVA, pf, V, A and Hz of class 0.5 accuracy

Lux meters

Measuring tape

On line energy meter instruments – (calibrated)

5. Measurements & Observation to be made:

While conducting the audit carryout a detailed survey for the

following

Monitor the condition of lighting fixtures

Lux measurements at various places (Number of measurement

to be carried out is given in the following sections)

Measurement of power parameters kW, kVA, Current, Voltage,

power factor, harmonics, frequency of all feeders

Room dimensions

Counting of installed fixtures Vs number of fixtures in operation

Maintenance practices – for cleaning, replacement, etc

6. OBSERVATIONS AND ANALYSIS

A. System familiarisation and operational details

Detailed interactions with the plant personnel have to be carried out to get familiarisation for system detail and operational details. Pre visit to the plant can be made to get familiarisation of lighting system

B. Observations on house keeping and maintenance

practices interactions and surveys to be carried out on :

House keeping measures in up keeping of luminaries

Failure rate of lamps and ballasts

Replacement procedure of failed lamps

Procurement options

Maintenance practices

Operational practices (on / off controls)

If any energy saving retrofits are installed in the plant then

the operational status of the retrofits can be assessed

Identify the areas where poor illumination and excess illumination is provided

Assess the various alternate lamps / luminaries applicable for various sections

Type of panel lamps or sign lamps used – to explore possibility of using LED lamps

Observations on other loads which are connected to the lighting circuit and their energy consumption

C. Exploration of energy conservation possibilities

While conducting the energy audit explore for various energy conservation measures such as

Look for natural lighting opportunities through windows and other openings. Derive way to improve natural lighting during the day time

In the case of industrial lighting, explore the scope for introducing translucent sheets

Use of energy efficient lighting methods / products / equipments /retrofits

Maximize sunlight use through use of transparent roof sheets, north light roof, etc.

Examine scope for replacements of lamps by more energy efficient with due consideration to luminaries, color rendering index, lux level as well as expected life comparison. Performance of luminaries which are commonly used are given in the Annexure

Replace conventional magnetic ballasts by more energy efficient ballasts, with due consideration to life and power factor apart from watt loss.

Select interior colours for light reflection.

Assess scope for delamping

Assess scope for re-arrangement of lighting fixtures

Modify layout for optimum lighting.

Providing individual / group controls for lighting for energy efficiency such as:

On / off type voltage regulation type

Group control switches / unitsis provided

Occupancy sensors

Photocell controls

Timer operated controls

Modify switches / electrical circuit

Install input voltage regulators / controllers for energy efficiency as well as longer life expectancy for lamps where higher voltages, fluctuations are expected.

Replace energy efficient displays like LED's in place of lamp type displays in control panels / instrumentation areas, etc.

Opt for better reflector in lighting

Cleaning of reflector at regular interval

In power plant, locations like HT/LT switchgear rooms, cable galleries etc which sites / locations are rarely visited, lighting circuits may be modified in such a way that keeping 25% to 30% lights always “ON” and remaining lights controlled by simple ON/OFF switch provided at the entrance of the room / hall

Opportunities to reduce the power consumption/ improve the energy efficiency of other loads which are connected to the lighting circuit

Some good practices in lighting are:

Installation of energy efficient fluorescent lamps in place of "Conventional" fluorescent lamps.

Installation of Compact Fluorescent Lamps (CFL's) in place of incandescent lamps.

Installation of metal halide lamps in place of mercury / sodium vapour lamps.

Installation of High Pressure Sodium Vapour (HPSV) lamps for applications where colour rendering is not critical

Installation of LED panel indicator lamps in place of filament lamps.

Light Control : Grouping of lighting system, to provide greater

flexibility in lighting control

Installation of microprocessor based controllers

Optimum usage of day lighting

Installation of "exclusive" transformer for lighting

Installation of servo stabilizer for lighting feeder

Installation of high frequency (HF) electronic ballasts in place of conventional ballasts

D Recommendations

Each energy conservation measure should discuss :The back ground

Analysis and suggestion

Energy savings evaluation (Estimated – before and after)

Impact on energy consumption after implementation

Economic feasibility

Investment required and payback period

Monitoring and verification of energy savings after implementation

Efforts and resources required for sustainability of energy savings

The vendors/ suppliers/ manufactures details

THANK YOU