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~.---i·COST Electronic &comll1unicmion

proceedings

13·15 ja~O II

Energy Audit in Industry -A case study of Centrifugal Pumps R.M.Hohnukhe

K.D.Deshpande

Electrical Engineering Department Bharati Vidyapeeth Deemed University College of Enggineering, Pune, India E-mail: rajeslunholmukhe@hotmaiLcom

Electrical Engineering Department Bharati Vidyapeeth Deemed University College of Enggineering, Pune, India E-mail: [email protected]

Abstract-s-, Energy conservation litis 1l0W become a necessity. Considerable energy saving is possible through proper choice of equiprnents, and their effective use. The-only feasible way to handle energy crisis, apart from capacity addition, is the efficient use of available energy. For this there is a need of optimizing energy, using standard systems and procedures so as to reduce energy requirements per unit of output.In this paper a case study of centrifugal

pump in industry

for energy

audit is presented.

Keywords-energy

audit,centrifuga!

pumps

Modeling and Simulation of Buck boost Controller of Solar Wind Hybrid Energy System IPatif S. N.

't». R.

2S.S. Patif

C Prasad

Asst. Prof. in Electrical Engg. Dept., P. V.P.lT Bavdhan, Pune lAsst. Prof. in Electrical Engg. Dept., Sinhagad Academy of Engineering, Pune, Jprof in Electrical Engg. Dept., College of Military Engineering, Pune I

Ipatil sn@rediffmaiLcom [email protected]

Abstractprices There

Because of combustion of fossil fuels global warming caused by environmental problems, the raising of crude oils and natural gases. They promote continuous effort to improve energy system and its efficiency. is a need to search for abundant and clean energy sources due to the depleted and increasing prices of oil.

Solar and wind energy acts as an alternative energy source. The objective is to design and simulate a controller for the unlimited a higher voltage output through the de-to-de converters (Buck-Boost

solar power drawn Converter). The

from the sun and produce Photovoltaic cells have a

non-linear V-I characteristics and adapts the Maximum Power Point Tracker (MPPT) to achieve the maximum permissible power obtained. A controller circuit is design to track the maximum power of the photovoltaic at the peak voltage and current level. De-to-De converters (Buck-Boost Converter) are necessary to produce a higher voltage due to the low input voltage drawn from the photovoltaic cells. The voltage is maintained at a constant voltage

at the output

and boost converter track the maximum

Keywords:

S.S.V.P.S.'s

Modeling,

load by the switching circuit power

control

circuit.

Wind

controller

circuitry

comprises

a non-inverting

The result shows that the model can simulate the photovoltaic models, wind which helps to design and improve the power of solar wind energy system.

Photovoltaic

B.S.Deore college

System,

of

Maximum

Power

Point Tracker,

Engineering & Polytechnic.Dhule.

Buck-Boost

system

buck and

Converter.

Page 28

Energy Audit in Industry -A case study of Centrifugal Pumps RMHolmukhe

K.D.Deshpande

Electrical Engineering Department Bharati Vidyapeeth Deemed University College ofEnggineering, Pune, India E-mail: [email protected]

Electrical Engineering Department Bharati Vidyapeeth Deemed University College ofEnggineering, Pune, India E-mail: [email protected]

Abstract-. Energy conservation has now become a necessity. Considerable energy saving is possible through prtIfIt!T duIia of ~ tBUl tJuir eff~ I!SL 1h 0III;y ftWSible ....., ID IuuuIk nID1:.F am.s. 1IJIIIIt.frotrt aqJIIdI:y IMI4iIimI. is tIu! ejJiL.inrt IISe of ~ I!III!I'VF", tIIis tlIen! is • .ed of opti-kirtg DIDV, IISiIrK sIIBIIItmI

sy.sIDIB

11IIIIprot:a/IIrt!s

:so

lIS

ID rrtIIu%

DfDV

~ per IIIIiI of twtpwt I. litis JIIIIN!' • ccse sIIuIy of centrifugal pump in industry for energy audit is presented. Keywords-energy

audit.centrifugal

L

pumps

lNrRoDUCl10N

An Energy Audit is the preliminary activity towards instituting energy efficient programs in the eslablishmentlt consists of activities that seek to identify conservation. Factors to be considered during energy audit are energy accounting, better control of energy use, process optimization for efficient energy use, creating awarness and foUowing standard rules and reguJations.Gener.dIy an Energy Audit includes survey of work place ,analysis of energy usagt;.SlUdyof energy use procedures,finding energy improvement opportunities ,recommendations with cost benefit analysis.. II.

THE ROLE OF AN ENERGY AUDIT

Identify areas in the establishment consuming unnecessarily too much energy. Assess energy saving opportunities so as to save money where it counts the most. In the factory, an energy audit increases awareness among plant personnel of energy issues. An energy audit gauges the energy efficiency of the plant against "best practices", when used as a "baseline" for tracking yearly programs against targets. h is the f"lTSt step towards saving money in the production pIanL

llI.

CONTENTS

OF AN AUDIT

An energy audit seeks to document things like energy being used on site per year which includes use of energy and

opporturuties for savings.In the process it assesses the effectiveness of management structure for controlling energy use and impIement:iI1g cbaoges.The energy audit report estabIisbes the need for plant metering and monitoring. The plant Manager then instititutionaIize the practices thus saving money fur the years to come:nM! energy audit action plan IisIs the steps and sets the preliminaIy budget fur-the energy managanent progranL

IV.

ANALYSIS

OF ENERGY

USE

Identifying areas where energy used is most useful.This enables to focus OIl areas where the andit should be focused and raises awareness of energy use and cost.The results could be used in the review of management stroctures and procedures fur controlling energy use. V.

IMPORTANT POINTS TO CONSIDER WHEN COLLECTING SITE LOAD DATA

Operating hours: It is collected from plant personnel..This data sbouJd be accurate so as to estimate energy savings correctly. Duty Cycle: Machines, such as large induction motors have varying loads with different power requirements.Hence duty cycle is very important Actual Power Consumed: For electric power users, this is based on either 3-phase current/voltage readings or power analyzer measurements(e.g. direct KW which incorporates power factor). For fuel users, tank readings of monthly consumption estimates and flow meters with totalization can be source of measurement. VI.

!DENTIFICA TlON OF ENERGY PROJECTS

In identifying energy ~ it is impor1ant to focus on major eIiergy users and areas.Always apply 80120 rule, focus OIl opportunities that provide XO'"/e of the savings but require 2()O/e inpuLSpeod more time on those projects which have shorter payback period.

YH COST BENEFITANALySIS

The identififxJ energy conservation opportunities should be anaiyzl:d in tenns of the costs of iq)IemeoIing the ~ versus the benefits that can be ~ makes a sense to go 011 with the project if there is a net positive benefit from the project.

VIII ACTION PLAN TO SET IMPLEMENTATION PRIORITY

After passing the cost benefit analysis test, an action plan should be developed to ensure that the opportunities identified are implemented.The action plan should include all the major steps for implementing the opportunity as well as the people responsible. Furthermore, there should be a plan to monitor the results. IX

TYPES OF ENERGY AUDTr

TypesofE.ergy AIlCIits The term Energy Audit tries to identify the alternative energy efficient measures that would also satisfY the financial criteria of the investors A demiled specification of the scope of work: is necessary to speU out the requirement of the audit. There are three common audit programs which are described in next pages. Prdimilary A.dit The preliminary audit also called as a simple audit, screening audit 01" walk: through audit, is the simplest and quicker type of auditsJt involves minimal interviews with the site operating personneI.a brief review of the fuciJity utility bills and other operating data, and a walk-through of the facility to become familiar with the plant operation and identify areas of energy waste or inefficiency .Major problem areas will be uncovered during this type of audit..Corrective measures are briefly described and estimates of implementation costs, potential operating cost savings, and simple pay back periods are provided.This helps to priotize energy efficient project and detennine the need for a more detailed audit.

Geaentl Alldit GeoeraJ audit or a mini audit/site energy at~it expands on the preliminary audit.More detailed information about facility operation is collected so as to perform a more detailed evaluation of energy conservation measures identified. Utility bills for a period of 12 to 36 months are coUected to evaluate the fucility's energy/demand rate sIructures and energy wage profiIesAdditiooal metering of specific energy- consuming systems is often performed to supplement utility data..ln-depth interviews with facility operating personnel are conducted to understand major energy consuming systems as well as insight into variations in daily and annual energy consumption and demand. A detailed financial analysis is performed for each measures to justify project implementation.

lnvestment-

Grade Audit

Facility's energy infiasbucture must compete with nonenergy related investment fur fur capital fimding Both energy and DOD-eIIeIgy investnlents are rated on a single set of financial criteria that generally stress the expected Return on Jnveslmen1(ROI)..Retm:n 011 Investment =Net Profit after taxesITotaJ InvestmentIhe projected operating savings fium the ~Jemetdation of energy savings should provide confidence to the investors.The investment-grade audit also known as a comprehensive audit,detailed audit, maxi audit or technical analysis audit expands on general audit providing a dynamic model of energy use of existing facility and all energy conservation measures identified. X

PUMP ENERGY REDUCTION

Pump system account for 13% of Electrical Energy Consumption in India.When analyzing the life cycle of pwnping equipment, the energy cost in operation is 85% for large water utility pumps.Selecting a bigher efficiency pwnp will reduce power consumpIion, but by improving the design of the pwnp system and cootrolling the interaction between the pwnp & the system would acbieve greater improvement,

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Figure NO.1. Pump system identification

If pwnp systems are initially designed on an energy efficient basis and pmnps are correctly operated & sized, the energy savings will often be in excess of 50%.lDe reasons for energy inefficient pumping system are Poor System Design,over sizing of pump,pump and system mismatching, pipe work layouts.Significant savings can be made in existing system by carrying out systematic audit & better operation eontrol.A study indicates that greatest energy consumption by pumps is in application in commercial & public buildings(41%), water & sewerage facilities(14%) and others (9010) as shown in fig.

EnergJ CcnsuqIIion bv ~or OIaldGi15

IIII!ria;; aid

~"UhIaI •••••

:11

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A

inaccurate.However the vananons form the original specified duty is so large that estimated actual performance fiom data which is available is sufficieut to to guide actions for energy reduction.. Trimming cost of an impeller inStead of Ibrottling can be recovered in a few days..For large pmnps where saving potentiaI are high. a specialists is employed who insIaUs tempotaay insmurc:adalions to accurately measure perlOnnance.

Figure o2J~DagyCOIl5UIDp6on by sedor"

Xl

CARRYING 0

A SYSTEM AUDIT

Purpose of energy audit is to reduce 'operating costs by reducing energy consumption. Energy audits carried out by IPMA shows that savings in the range 30 to 50% are not unusual.By reviewing utility bills one can get an indication of the savings to be made and the estimate of investment to be made into auditing process.In most industrial sites two thirds of the energy is consumed by electric motors.The cost of energy consumed by motor during its life time may be 100 times its purchase cost.Through modem design techniques, this loss can be reduced to 30%.Many pumps & motors are operated at full power constantly, irrespective of process needs, and in some sites this offers the potential of large cost reductions.An energy audit is a significant investment and many man-hours are needed to find out where energy is consumed. A thorough log of consumption on each spur is made because excess energy is sometimes used in most unlikely place.An energy audit identifies savings to be made by resizing or retrofitting pumps which are operating away from their best efficiency points.Variable speed motors in place of standard motors can be used to control pump operations.By studying process requirement, energy audit can identify requirement of energy consumption and compares it with actual consumption.lf every pump and motor is working at the maxm. efficiency, great savings can be achieved. Performance data for the equipment as originally supplied or manufacturers curves are required to carry out the audit.From the name plates of the pump and motor data can be recorded.Determination of actual flows and pressures may be difficult at site due to non-availability of pressure gauge and flow meters. Power readings on site may often be

Figure No3. Pump

XII.

A CASE STUDY OF CENTRIFUGAL PUMPS

Existing pump details:Kirioskar pump model DB 50/20,size (65x50)mm,Pump sr. no.9370757,58 Head: 46 mtrs Discharge: 6 Ips Pump efficiency: 47% BKW: 5.75 Motor: 7.5KW/IOHP,TEFC induction motor Observations: 1Pumps operating 6hrs per day 2Pumps operated at full capacity Suggested pump Kirloskar Pump Model DB 40/20,size (65x40)mm Head: 46 mtrs Discharge: 61ps Pump efficiency: 54% BKW:5KW Motor recommended 5.5KW/7.5HP TEFC industion motor Cost Benefit Analysis C =(n2-nl) x PxZxSx 0.746/n] C= (54-47)xlOx2J90x7.5xO.746/54 = Rs 14825 per year Cost of new pump type DB 40/20 with 5.5HP motor = Rs 12030 Pay back period = 10 months. Total saving during full life(15 yrs) = Rs 2,22,375 each pump.

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RESULTS

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ACKNOWLEDG lENT

Bharati Vidyapeeth Engineering, Pune.

Deemed

University

REFERENCES

[I]

Field Visitsin various industries

[2]

Manuals of Kirloskar motors and pumps.

[3]

Handbook of Energy Conservation.

[4]

Various IEEE papers on motors and pumps.

College

of