Proposal for Energy Saving / Monitoring Equipments For New College of Engineering Project @ Qatar University INDEX SL.NODescriptionTAB 01Energy Management & Control System TAB-A 02Advantages of Variable Frequency Drive in Energy Management and Control System TAB-B 03Energy Management Presentation TAB-C 04Proposed BTU Meter Location Drawing TAB-D 05Proposed VFD Details TAB-E 06Proposal for VFD & BTU Meters TAB-F TAB-A Energy Management & Control System Energy Management and Control System: Desired Capabilities and Functionality

P r o j e c t : Ne wCo l l e g eOf En g i n e e r i n g@ Q a t a r U n i v e r s i t yD o h a Q a t a r 1 Energy Management and Control System:Desired Capabilities and Functionality Contents SL. NODescriptionPage No 01SummaryPage -04-04 02NomenclaturePage -05-06 03IntroductionPage -07-08 04Functions and Capabilities of Energy Management Control Systems (EMCS) Page -09-10 05Central Information Processing and Control WorkstationsPage -10-10 06Day-to-Day OperationsPage -10-11 07Basic FunctionsPage -12-12 Scheduling FunctionPage -12-12 Supply-Air Temperature Reset FunctionPage -13-13 Static Pressure Reset FunctionPage -13-13 Thermostat ControlsPage -13-14 Start/Stop OptimizationPage -14-14 Economizer ControlsPage -14-14 AlarmingPage -14-15 Access to Sensor and Equipment Performance DataPage -16-16 08Intermediate FunctionsPage -17-17 Demand Limiting (Load Shed / Load Rolling)Page -17-19 Duty CyclingPage -19-19 2 Energy Management and Control System:Desired Capabilities and Functionality SL. NODescriptionPage No Event Initiated ControlsPage -19-20 Load ShiftingPage -20-20 09Advanced FunctionsPage -20-21 Automated Fault Detection and DiagnosticsPage -21-21 Monitoring Simultaneous Heating and CoolingPage -21-21 Tracking Energy-Use.Page -21-21 Whole-Building OptimizationPage -21-22 Whole-Site Optimization, Integration plus SecurityPage -23-23 10Cost vs. BenefitsPage -24-25 11Commissioning EMCSPage -26-26 12Operator Skills and TrainingPage -27-27 13Control-System MaintenancePage -28-28 3 Energy Management and Control System:Desired Capabilities and Functionality Energy Management and Control System: Desired Capabilities and Functionality Project Name: New College Of EngineeringQatar University State of Qatar Client:Qatar UniversityState of Qatar Project Consultant: Kathib & AlamiPO Box No 10281Doha Qatar Main Contractor: AL Darwish Engineering WLLPO Box No 183Doha Qatar MEP Contractor: ETA StarDoha Qatar Prepared for Project:Prepared By: New College Of EngineeringShahjan Trading Company W.L.L Qatar UniversityPO Box 8689 State of QatarDoha Qatar 4 Energy Management and Control System:Desired Capabilities and Functionality Summary Energymanagementandcontrolsystem(EMCS)technologyhasevolvedoverthepastthree decadesfrompneumaticandmechanicaldevicestodirectdigitalcontrols(DDC)orcomputer basedcontrollersandsystems.Today'sEMCSsystemsconsistofelectronicdeviceswith microprocessorsandcommunicationcapabilitiesandutilizewidespreaduseofpowerful,low cost microprocessors and standard cabling communication protocols. Thisdocumentdiscussesfunctionsandcapabilitiesofatypicalbuilding/facilityEMCS.The overallintentistoprovideabuildingoperator,managerorengineerwithbasicbackground informationandrecommendedfunctions,capabilities,andgood/bestpracticesthatwillenable thecontrolsystemstobefullyutilized/optimized,resultinginimprovedbuildingoccupant quality of life and more reliable, energy efficient facilities. Most basic functions and some intermediate and advanced functions described in this document aregenerallyrequiredtooperatebuildings/facilitiesefficiently.Acarefulreviewofthesite specific requirements is recommended before picking the functional requirements of an EMCS. It should be noted that the basic functions described in this document are generallyavailable in most EMCS systems, while the availability of the intermediate and advanced functions varyby manufacturer. 5 Energy Management and Control System:Desired Capabilities and Functionality Nomenclature AFDD: Automatedfaultdetectionanddiagnosticsinvolvestheuseofsoftwaretoolstoanalyze thebehaviorofthebuilding,determineiftheperformanceisunsatisfactory(fault detection)andthenisolateorlocalizethefaulttofacilitaterepair(faultdiagnosis).The behavior may be observed in the course of an active functional test performed by the tool or in the course of passive monitoring of routine operation. BACnet:BACnet is a data communication protocol for building automation and control networks developed by American Society of Heating, Ventilation, and Air Conditioning Engineers ANSI/ASHRAE 135-1995. A data communication protocol is a set of rules governing the exchange of data over a computer network. BAS:Building automation systems, also known as EMCS. BMS: Building management systems, also known as EMCS. Cascading Resets: an example of cascading resets is when both the chilled-water supply temperature as well as the supply air temperature is reset in a sequence. Commissioning: AprocesstoensurethatEMCSisdesigned,installed,functionallytested,and capableofbeingoperated&maintainedaccordingtotheowner'soperational needs. Controller:Processesdatathatisinputusuallyfromasensorperformslogicaloperations based on the device being controlled and causes an output action to be generated. Economizer:Air-side economizers use controllable dampers to increase the amount of outside-air intake into the building when the outside air is cooler than the return air and the building requires cooling. Demand limiting:acontrolfunctionthatenablesmanagementofpeakdemandlevelbyshedding predefined loads when the building/facility demand nears a preset maximum. DDC:Direct digital controls, also known as EMCS. DDE:DirectdataexchangeisastandardMicrosoftWindowsmessage-passing protocol that defines a mechanism for Windows applications to share information with one another. Distributed Facility Management: Management of building and facilities that are distributed over a widegeographicalregion.Althougheachbuildinghasitsown EMCS systems, the buildings are also managed remotely from a centrallocationthroughuseofgatewaysandsoftware applications. EMCS: Energy management control systems FMS:Facility management systems, also known as EMCS. 6 Energy Management and Control System:Desired Capabilities and Functionality Gateways:Devicesthatallowforintegrationofcontrolnetworkswith internet,sothatthedevices/controllersonthecontrolnetwork can be accessed through the Internet Interoperability:Abilityofadevice/controlleroraproducttoworkwithother devices/controllers or products without special effort on the part of the customer. Latent Cooling:Moisture removal through dehumidification LonTalk:AcommunicationprotocolforLonWorksdevicesto communicate with each other on a LonWorks network. LonWorks:A networking platform created by Echelon Corporation. MODBUS:AstandardcommunicationprotocoldevelopedbytheModicon Corporation.TheMODBUSprotocolisoftenusedinfacility metering applications. OLE:Object linking and embedding is like DDE, a standard Microsoft Windowsmessage-passingprotocol,whichdefinesa mechanismforWindowsapplicationstoshareinformationwith one another. Ratchet Clause: Aterminacustomerscontractorrateschedule(tariff)that dictates that thecustomersbillingsforeachbillingperiodmust be based at least in part on the maximum billing received by that customer over a given period, usually the preceding year. Sampling Interval:Theintervalbetweentwoconsecutiveadjustmentsofcontrol parameters. Settling Interval:Time required for the control to settle after a change in a control parameter. Temperature Reset:Adjustmentofsupplytemperaturehigher(duringcooling)or lower (during heating) to match the heating and cooling needs. Web-Enabled Device:Devicethatcanbedirectlyaccessedfromastandardinternet browser. 7 Energy Management and Control System:Desired Capabilities and Functionality Introduction Energy management and control system (EMCS) technology has evolved over the past 3 decadesfrompneumaticandmechanicaldevicestodirectdigitalcontrols(DDC)orcomputer basedcontrollersandsystems.Today'sEMCSsystemsconsistofelectronicdeviceswith microprocessorsandcommunicationcapabilities.Widespreaduseofpowerful,low-cost microprocessors, use of standard cabling, and the adoption of standard communication protocols (such as BACnet, LonWorks, and MODBUS) have led to today's improved EMCS systems. MostmodernEMCSsystemshavepowerfulmicroprocessorsinthefieldpanelsand controllersthatwillsoonbeembeddedinsensorsaswell.Therefore,inadditiontoproviding betterfunctionalityatalowercost,theseEMCSsystemsalsoallowfordistributingthe processingandcontrolfunctionstothefieldpanelsandcontrollerswithouthavingtorelyona central supervisory controller for all functions. Although true interoperability is still myth rather thanareality(asdiscussedlaterinthisreport),anewEMCSinstallationshouldconsider standardprotocols(suchas:BACnet,LonWorks,andMODBUS,etc.),web-basedorweb-enabled controllers, and control networks that can be integrated with the internet and intranets. Theopenprotocolquestionhastobeansweredwithagreatdealofthoughtand engineering. Currently BACnet and LonWorks are the two most popular, truly open protocols for useincommunicationsbetweenman-machineinterface(MMI)orfront-endsandlowertiered controllers. MODBUS is used widely in the Supervisory Control and Data Acquisition (SCADA) orutilitysideofsystems.Ifyouwanttointegrateyourwasteandwatertreatmentplantsalong with utility electrical monitoring, then MODBUS can be used to bring these operations on to the mastersiteEMCSoperation.Thisthenallowsforfarbettercontrolandintegratedoperations between different divisions into one shared system. When determining whether to go to an open orclosedprotocol,onemustlookattheactualapplicationandwhereitwillbeapplied.Open protocols allow for more than one vendor to talk to a master controller and share basic point data only.Itdoesnotallowforcodingandprogrammingfunctionstotakeplacebetweendifferent vendors.YoucannotusevendorAssoftwaretoprogramvendorBscontroller.Youmustuse eachvendorssoftwareandproprietarytoolstoprogramorchangetheprogramwithina controller. This option does not apply to front-ends or MMIs. Some front ends or operator work stationscansharedatausingdynamicdataexchange(DDE),OPCorotherinformationsharing protocol.YouwillgenerallynotwantmorethanoneMMIorfront-endonasitebecauseof training and operational requirements. Anotheroption,ifyouareworkingwithnewersystems,isweb-basedsystems.These systems can use standard web browsers to view pages of data. They are currently more limited in programming and capabilities than older systems. They do have a place in some installations and should be considered. Higher security concerns play a part when you start to apply a web-based system.ExamplesofagoodapplicationforBACnetmightbeaTranechillerinterfacetoan EMCSsystem.Apoorexamplewouldbetotakeanexistingbuildingandaddoneortwo BACnetdevicesintoanoperatingproprietarysystem.Also,trainingmustbeweightedintothe decision.Ifyouperformsoftwaremaintenanceinhouse,thenmorethanonevendorstraining may be required, if you purchase from more than one vendor. 8 Energy Management and Control System:Desired Capabilities and Functionality WhenanewEMCSinstallationisbeingconsideredorareplacementofanexisting EMCS is being planned, a detailed plan is essential. The plan should address the following items 1. Current Installed EMCS System a. Hardware b. Work stations, operator interfaces c. Communication d. Interoperability e. Salvageable pneumatic or conduit infrastructure 2. Planned Installations 3. Analysis a. Cost issues b. Procurement/contracting limitations and requirements c. Standard/open protocol considerations d. Accuracy requirements/types of applications e. Current use of system f. Future needs g. Training needs h. Commissioning needs 4. Internal Issues/Perspectives 5. Capabilities of Local Control Vendors a. Products b. Resources (qualified people, response times) 6. Need for Standards a. Specifications b. Sequences 7. Existing Base EMCS Infrastructure and Compatibility. 9 Energy Management and Control System:Desired Capabilities and Functionality Functions and Capabilities of Energy Management Control Systems (EMCS) AnEMCSmaybeknownbyvariousothernamessuchas:buildingautomationsystem (BAS),buildingmanagementsystem(BMS),energymanagementsystem(EMS),andfacility managementsystem(FMS).Forthisdocument,theEMCSisexplicitlydefinedasthesensors, transmitters, data acquisition, and data processing performed at the user (building) level as well as data and control systems that are more global to full campus control schemes. TheEMCSmayalsohaveaglobalsupervisorycontrollertoperformhigh-leveltasks(e.g., resettingtemperaturesetpointsbasedonbuildingconditionsandschedulingon/offtimes).The hardwaregenerallyconsistsofadistributedcomputerenvironmentwithsmartcontrollers strategically located throughout the system (buildings and base-wide network). Several network terminals or PC computers can be attached to these networks to provide a man-machine interface (MMI). ThereareawidevarietyoffunctionsanEMCScanperform,dependingonits capabilities.Ataminimum,theEMCShasasensor(s)tomeasureacontrolvariable(s)(e.g., temperatureandflowrates,SupplyFanSpeed),acontrollerwiththecapabilitytoperform logicaloperationsandproducecontroloutputs,andacontrolleddevice(s)thatacceptsthe control signals and perform actions (e.g., move dampers and valves), as shown in Figure 1. Figure 1. Schematic of an Example Control Loop Interfacesystemsareusedtointegratetolowerlevelpackagedcomponents.EMCS modulesofthistypeareableto"integrate"orconnectandcommunicatetofacilityplant equipment,whichhasmicroprocessor-basedcontrols.Thedifferentvendortypesofequipment thatthesemodulescanconnecttoinclude:variablespeeddrives,powermeteringequipment, electricalswitchgear/uninterruptiblepowersupply(UPS),etc.andotherpackagedHVAC 10 Energy Management and Control System:Desired Capabilities and Functionality equipment, which are microprocessor-based. These interfaces give a global management strategy that encompasses entire building and site complexes. Maincontrolpanelsconsistingoflocalareanetwork(LAN)interfacesandlowerlevel communicationsshouldbestrategicallylocatedinbuildingsthroughoutthefacility.These modules will allow for direct communication to laptop computers and support of all lower level functions.ThesoftwareshouldbedevelopedtotakeadvantageoftheMicrosoft"Windows" operatingenvironment,wherebytheuserscanopenmultiplewindowssothattheycanaccess andmanipulatemassquantitiesofdata.Windowsfeaturesshouldbeincorporatedintothe system design, such as mouse point-and-click operations. Central Information Processing and Control Workstations The operator workstations for an EMCS are normally desktop, medium to high end style Pentium or better and should be "Microsoft Windows" based PCs. The workstations should be connected directly into the LAN or directly to any main control panel. A radio-networked laptop PC in an operator truck can also be linked via a radio modem to provide full access to the systems for mobile maintenance and operations staff. Day-to-Day Operations The day-to-day operations and control of environmental conditions (temperature, humidity, and air flow) enable the facility managers to have remote, unrestricted access to environmental information on each building or piece of equipment that is part of the EMCS. This access allows for remote and immediate diagnostics and troubleshooting of system conditions. Buildings with EMCS direct digital controls incorporated into the design allow for adjustment of: temperatures, humidity, supply and exhaust duct static pressures and air flows, equipment run times, special condition monitoring, and other environmental conditions that are incorporated into the EMCS design for that particular building. Most facilities with EMCS controls are designed with automatic recovery mechanical and electrical systems to start backup equipment in case of a fault in normal operations. This happens without operator actions and at the instance of failure. In most instances, automatic recovery prevents faults from interfering with the day-to-day operations. These events happen in the background, and alarms and notifications are made without impact on the facility. These automatic control features are the best business investment of the EMCS system and are invaluable when compared to down time, reporting cost, or environmental accidents. Facilities can also be designed to be fully, remotely controlled and monitored in case of an event in a building causing evacuation. This limits the exposure of personnel during a hazardous event. EMCS is not a new concept for Qatar Civil Defense (QCD) activities. The desired functions and capabilities are summarized in Table 1. 11 Energy Management and Control System:Desired Capabilities and Functionality Table 1 Summary of Desired EMCS Functions and Capabilities 12 Energy Management and Control System:Desired Capabilities and Functionality Basic Functions Functions in the Basic group include a minimum set that is required to operate a building: scheduling,supply-airtemperaturereset,thermostatcontrols,andstartstoptimeoptimization, economizercontrols,alarming,andtheabilitytoseamlesslyexportsensorandequipment performance data to third-party software applications. A.Scheduling Function ThesinglemostimportantfunctionofanEMCSistheabilitytoscheduletheoperationof majorequipment(e.g.,air-conditioners,lights,SpeedControl).Abuildingthatisnotoccupied 24-hours per day does not require comfort conditioning, ventilation and comfort lighting during unoccupiedperiods.Thissavesnotonlyenergy,butalsounnecessarywearandtearon equipment leading to unplanned maintenance costs. The goal is to have as much maintenance planned, hopefully anticipated just before failure, signaled by control system data. This results in the added bonus of extending facility equipment life.Theresultindollarsavingstothecustomerisbothimmediateandlongterm.Inabilityto properlycontrolmajorequipmentorend-usesduringunoccupiedperiodscanincreaseenergy consumptionsignificantly(by15%orhigher)dependingonthelengthsoftheoccupiedand unoccupiedperiods.Inareaswithhighhumiditylevelsduringpartsoftheyear,limited operations at night might be required. Indoor sensors will be required to know when the system is getting near dew points and water may start to condense onto walls or colder objects. During dryer times, systems can remain off. To handle special events, if a building is occupied beyond the normal operating hours, many EMCSsystemsprovideatemporaryschedulingoroverridefeaturetodisablethenormally scheduled operation.If the override feature is enabled, it should be implemented in sucha way thatitistemporary,i.e.,thescheduleautomaticallyrevertsbacktonormaloperationswithina fewhoursorthenextday.Iftheoverrideisnottemporaryordoesnothavetheabilitytoreset itselfthefollowingday,themajorequipmentinthebuildingwilloperateduringunoccupied periods,wastingenergy.Ifthesystemwillnotrevertbacktonormalautomatically,thena procedure should be in place to remind operations to release all overrides when appropriate. The scheduling functions must allow programming of special schedules for weekends, holidays, anddaylightsavingstime.Theequipmentandend-usesthatbenefitfromschedulinginclude: ventilation, exhaust and supply fans (interior and exterior) and security lighting, packaged HVAC equipment, air-handling equipment and other miscellaneous. Some of this equipment can be off during the day and only on at night or during required use times. Most would be off when the facility is unoccupied Recommendation: Theschedulingfunctionisoneofthemostimportantfunctionsin operating the building efficiently, and therefore, is highly recommended. 13 Energy Management and Control System:Desired Capabilities and Functionality B.Supply-Air Temperature Reset Function For constant-air volume (CAV) air-handling units, the supply-air temperature can be reset basedonthezoneconditions.Whenthezonesareatalightloadcondition2,resettingthe supply-airtemperaturewillreducethecoolingandreheatenergyconsumption.Typically,the supply-airtemperatureonvariable-airvolume(VAV)systemsisheldconstantbecausethe volume of the air is modulated to meet the zone load. Recent studies, however, have shown that thesupply-aircanberesetforVAVsystemsaswell,althoughthecontrolssequenceismore complex. Recommendation: Resettingsupply-airtemperatureduringpart-loadconditionscan save energy; therefore, this function is recommended for constant-airvolumesystems.Foravariableair-volumesystem,thereis tradeoff between the fan and the cooling/heating energy. Also, the controlalgorithmsaremorecomplex.Thisprocedureisnot recommended with variable- air volume systems unless a thorough site-specific analysis is done and the results are favorable. C.Static Pressure Reset Function Forvariable-airvolume(VAV)air-handlingunits,thesupply-airstaticpressurecanbe reset based on the zone conditions. When the zones are at a light load condition, resetting the supply-air static pressure will reduce the cooling and reheat energy consumption. Typically, the supply-air pressure on VAV systems is held constant because the volume of the air is modulated tomeetthezoneload.Recentstudies,however,haveshownthatthestaticresetbasedonthe zones with the highest damper conditions can save large amounts of energy. Some systems have been seen to run as low as 0.25 inches at lighter loads compared to a 1 to 2 inch normal set point. Recommendation: Resettingsupply-airstaticduringpart-loadconditionscansave energy;therefore,thisfunctionisrecommendedforvariable-air volume systems. D.Thermostat Controls Thermostatsareusedtocontrolthecomfortconditions.Incommercialbuildings,a typical HVAC zone has a number of sub-zones (rooms) all served by a single heating or cooling unit,whichiscontrolledbyasinglethermostatlocatedinonlyoneofthesub-zones.Ifthe internalloads(e.g.,equipmentinthespace,numberofoccupants,etc.)andexternalenvelope loads(i.e.,heatgainorlossthroughexteriorwalls)areuniformacrossallroomsinasingle HVACzone,asinglethermostatisadequatetomaintainthecomfortacrossrooms.Inmany cases, however, the loads are not uniform across the zone. One way to avoid hot or cold spots is to install a number of temperature sensors (wireless or wired) across the zone (e.g., one in each room)andthentousetheaveragevalueofthesensedtemperaturesinthezonetocontrolthe HVAC equipment.It is important to have the ability to reset the thermostats remotelyfrom the centralEMCSworkstation.Thiswillallowfortemperaturesetupduringunoccupiedsummer periodsandtemperaturesetbackduringunoccupiedwinterperiods.Itwillalsoprovidea 14 Energy Management and Control System:Desired Capabilities and Functionality mechanism to shed loads during supply shortages or during demand-limiting periods. The ability tosetupandsetbackthermostatsreducesenergyconsumptionofsupplyfans,packaged equipment, chillers, boilers, and air handlers. Recommendation: Thermostatcontrolswithremotemonitoringandsetpointcontrol that are integrated with EMCS systems are highly recommended E.Start/Stop Optimization Start/stop optimization or temperature/time optimization, as it is sometimes referred to, is an improvement over simple setup/setbacks. Setup/setbacks are based on time-of-day, while the start/stopoptimizationstrategyaccountsforoutdoor-airconditionsandcanincludethermal storage of building mass to determine when to startup and setback the HVAC system operation. TheoptimizedstoptimepermitscertainHVACsystems(e.g.,chillersandboilers)tobeshut downbeforetheendoftheoccupiedperiod(e.g.,10to15minutes)andallowsthezone temperature to float within acceptable comfort levels. Similarly, the optimized start time permits certainHVACsystems(e.g.,boilersandchillers)tostartjustintimetoallowforthezone conditions to reach the acceptable range just when the zone begins to be occupied. Recommendation: Optimumstart/stopfunctionisdesirablewherebuildingsarenot occupied24-hours.Eveninbuildingsoperated24hoursaday,7 daysaweek,therearegenerallyseveraltimezonesthatcanbe shut off to reduce energy usage during some hours of the day. F.Economizer Controls Incoolingmode,thereareanumberofhourswhentheoutsideairiscoolerthanthe return-airstream.Useoffreecoolingwhenoutsideconditionsarefavorableisreferredtoas airsideeconomizing.Aneconomizercyclecanbeemployedonbuilt-upAHUsaswellason packaged unitary products, generally referred to as roof top units. For built-up AHUs, the EMCS mustprovidethenecessarysequenceofoperationsfortheeconomizercycle,whilemost packagedunitscomeequippedwitheconomizercyclesandbuilt-ineconomizercontrols.The coolingenergysavingsfromuseofaneconomizercyclerangefrom15%to50%;theprecise savings depending on the type of economizer cycle employed and the climate location. The most commonly used economizer control strategies are: 1. Differential dry-bulb temperature based, 2. Differential enthalpy-based,3. high-limit dry-bulb temperature-based, 4. high-limit enthalpy-based. Withdifferentialcontrolstrategies,theoutside-airconditioniscomparedwiththereturn-air condition. As long as the outside-air condition is more favorable, outside air is used to meet all orpartofthecoolingdemand.Anexampleofafavorableconditionwithdry-bulbtemperature control would be the outside-air dry-bulb temperature being less than the return-air temperature. 15 Energy Management and Control System:Desired Capabilities and Functionality If the outside air alone cannot satisfy the cooling demand, mechanical cooling is used to provide the remainder of the cooling load. With high-limit control strategies, the outside-air condition is compared to a single set point or fixed set point, usually referred to as a high limit. If the outside-airconditionisbelowthesetpoint,thenoutsideairisusedtomeetallorpartofthecooling demand;theremainderofthecoolingloadisprovidedbymechanicalcooling.Althoughthe sequence of operations for economizer control appears to be simple, the failure rate in the field is veryhigh.Afaultyorimproperlyoperatingeconomizercycleisdifficulttodetectbecausethe heating/coolingsystemgenerallycompensatesforthefailurebyprovidingmoremechanical heating or cooling, and no occupant discomfort is noticed. Recommendation: Properlyoperatingeconomizercontrolscansavesignificant coolingenergyconsumptionandarehighlyrecommended.Indry climates(e.g.mostofwesternU.S.),dry-bulbdifferentialbased economizercontrolsarepreferred,whiletheenthalpy-based controlsarepreferredinhumidclimates(e.g.,mostofthemid-westandsouthernU.S.).Ineithercase,comparingthereturn-air conditionstotheoutside-airconditions(differentialcontrol)has significantgainsovertheolderhighlimitsetpointtypecontrols (highlimitcontrol).Thiscontrolalgorithmalsoneedsto coordinate with the heating and cooling controls. G. Alarming EMCSprovidesthefunctionofalarmannunciationanddisseminationforthesystems currently connected directly to a central location. This provides early detection of trouble/critical alarmsduringnormalandoff-shifthours.Duringoff-shifthours,whenmanpowerisgreatly decreased, the value of EMCS alarm notification and central location relay and response cannot be underestimated. Theimmediatebenefittousersincludestheeffectivemonitoringofcriticalbuildingsand utility functions, which is a necessary ingredient to the total operation of the individual buildings andtheentirecampusasawhole.Thisensuresthattheinvestmentineachofthebuildingsis protected and not compromised by enabling an immediate and quick response to any building or utilityfailure.Alarmsareusefulindetectingmanyabnormalconditionsinbuildings.For example,theabilitytomonitorthespacetemperatureandcreateanalarmwhentheconditions deviatefromtheacceptablerangecanbeusefulinmitigatingproblemsbeforetheoccupants complain. All modern EMCS systems provide such alarming functions. Recommendation: Alarms are strongly recommended. They are useful in both day-to-day operations and the maintenance of buildings and facilities. The receiving alarm computer or station does not have to be manned if alarmsaretransmittedautomaticallyviapageroremailtothe appropriate staff 16 Energy Management and Control System:Desired Capabilities and Functionality H.Access to Sensor and Equipment Performance Data Having an EMCS in every building is not sufficient to address the growing needs of the facility manager and operator. Many of the intermediate and advanced functions, described in the following section, are generally not available in most EMCS systems. They have to be developed and integrated in-house or by a third-party software provider because EMCS vendors are unlikely to provide this functionality in the near future. Keys for successful implementation of these functions is easy access to sensor, controller and equipment performance data distributed throughout the facility on a control network managed by EMCS and networks that tie the EMCS with the rest of the enterprise (internet or intranet). This will lead to the next generation of distributed facilities management systems. Without easy access to data, it would be difficult to realize all the benefits of distributed facilities management. These benefits include: Lower energy expenses, Fewer occupant complaints and faster resolution of problems, Reduced liability and litigation expenses, relating to indoor air quality (IAQ) issues, Improved performance of occupants because of a better indoor environment. Although the details of data gathering depend on the type of EMCS and the protocols it supports, most EMCS systems provide some standard methods to access data from geographically distributed facilities. Many EMCS manufacturers provide DDE/OLE Direct Data xchange/Object Link and Embedded servers to facilitate data exchange between controllers/devices and software application programs. Having an EMCS that supports a standard data exchange method (e.g., DDE, OLE, BACnet, LonTalk) does not guarantee success. For example, a third-party application that can import data from one EMCS using a standard data exchange method might not work with another EMCS, although both EMCS systems support the same standard. Most EMCS manufacturers support trend logging for sensor, controller and equipment data, which are generally not in a standard format. Although trend logs are useful, they require some pre-processing before they can be directly used with third-party applications. In addition, the logs are generally not available in real-time, and it is difficult to automate functions using trended data. Therefore, trend logs should not be confused with real-time direct access to sensor, controller, and equipment data through use of standard communication or data exchange protocols (DDE/OLE, BACnet, MODBUS or LonWorks). Recommendation: Theabilitytoextractdataisessentialforimplementationof functions that are not directly supported by theEMCS. Therefore, onlyconsiderthoseEMCSsystemsthatsupportstandarddata exchangemethods(DDE/OLEorBACnet).Thesefunctionsare critical if the EMCS system is planned to gather meter, run time or otherdatatoimportintoanothersoftwarepackage.Thesemight bemaintenancerequesttrackingpackagesorutilitymonitoring packages. 17 Energy Management and Control System:Desired Capabilities and Functionality Intermediate Functions Functions that fall in the intermediategroup include: demand limiting (load shedding or loadrolling),loadshifting,dutycycling,andeventinitiatedcontrolsandmonitoring simultaneous heating and cooling. A.Demand Limiting (Load Shed / Load Rolling) Insomeregionsofthecountry,demandchargescanbeasignificantfractionofelectricity costs.Oftenutilitieshaveratchetclausesthataffectthebilledpeakforthenext12months. Demandlimitingisonewaytocontrolexcessivedemandcharges.Itallowsforsystematic shedding of electric loads when the peak demand of the building approaches a preset level. Many chillershavedemandlimitingfeaturesthat,whentriggered,limitthepowertothecompressor. ThiscanalsobeimplementedinanEMCS.Demandlimitingsupervisorycontrolsmustensure that the desired demand limit is not exceeded at any time during the month or the season. Some advancedcontrolfeatures,suchasbuildingpre-coolingandpre-heating,canhelpalleviate uncomfortable conditions when AHU or chiller usage is limited during demand limiting periods. For illustration purposes, consider the following example: AfacilityhasanEMCSsystemcapableofautomaticallyrunninganindependentload sheddingsoftwarescheme.Thesequencereadsthebasemeterelectriccurrentratedataand broadcasts,overtheindependentnetwork,demandlevelsforthebuildingstofollow.Demand levels follow the base utility rate structure for costing demand. The facility rate structure has the following three peak time periods: on-peak, partial-peak and off-peak. The peaks are defined as follows: Summer months, March through October: 1. On-peak: 12 noon thru 6:00 P.M., Monday thru Friday, excluding holidays, 2. Partial-peak: 8:30 A.M. through 12 noon and between 6:00 P.M. through 9:30 P.M., Monday thru Friday, excluding holidays, 3. Off-peak: 9:30 P.M. thru 8:30 A.M., Saturdays, Sundays and all holidays. Starting at 11 A.M., the EMCS system starts ramping down, so that the systems are able toachievesetpointatthestartoftheOn-peaktimeperiod.DuringtheOn-peaktime frame, the EMCS systems will control to the On-Peak prescribed kilowatt (kW) demand limitset-pointmaximum.DuringthePartial-peakperiodstheEMCSsystemscontrolto theprescribedPartialpeakKWdemandsetpointvalue.Allotherdaysandtimes,the EMCS system will control to the Off-peak prescribed kW maximum setting Winter months, November thru Feb: 1. On-peak: none 2. Partial-peak, 8:30 A.M. thru 9:30 P.M., Monday thru Friday, excluding holidays, 3. Off-peak:9:30P.Mthru8:30A.MweekdaysplusSaturdays,Sundaysandallholidays. During the partial-peak time frame, the EMCS system will control to the partial-peak kW demandsetpointvalue.Duringallotherdaysandtimes(off-peaktimes),theEMCS system will control to the off-peak prescribed kW setting. Each of the three demands time 18 Energy Management and Control System:Desired Capabilities and Functionality slots have a corresponding maximum kW set point. Thesewould be notto exceed set points. For this example: 1. The meter allocation was 12.6 megawatts 2.Thenottoexceedsetpointforalltimeframeswas12megawatts.Themainload sheddingsoftwarewasdesignedtohave10separategroupsand4controlstages,as defined below. Buildings were assigned to specific groups, based on priority, with the 1st group being the least important (most capable of withstanding environmental change) and the10thgroupbeingthemostimportant(leastcapableofwithstandingenvironmental change). Group 1 executes load shedding first and group 10 executes load shedding last. AsthekWlevelrisesbecauseofincreasedload,the1stgroupexecutesstage1load limiting,followedbyGroup2,etc.untilallgroupshaveactivatedstage1.Afterall groupshaveexecutedstage1,andthedemandlevelcontinuestoclimb,group1would executestage2,followedbyGroup2,etc.,untilallgroupshaveexecutedstage2, followed by stage 3 and 4, respectively. Caution, there should be a gradual ramp down of thesetpointspriortoon-peaksettingtobalancetheloadsasthesystemscomeinto alignment. Master load shed/load roll group settings: Target Base Load 12000 kW Stage 1 Stage 2 Stage 3 Stage 4 Group 1 11600117001180011900 Group 2 11610117101181011910 Group 3 11620117201182011920 Group 4 11630117301183011930 Group 5 11640117401184011940 Group 6 11650117501185011950 Group 7 11660117601186011960 Group 8 11670117701187011970 Group 9 11680117801188011980 Group 10 11690117901189011990 Building Load shedding stage definitions/scheme: Eachfacilityshallbeassignedagroupnumber.Anexamplewouldbefacility333mightbe assigned to group 6, meaning it would be load shed near the middle of the priority scheme. TheEMCS system in the building listens for the broadcast of a demand level from the master meter and changes its sequenced control per the following. DEMAND LEVEL # 1: Resets T/Stat setpoints out 1F from current setpoints. DEMAND LEVEL # 2: Resets T/Stat setpoints out 2F from original setpoint and limits chilled water valves to 75% of full open capability. DEMANDLEVEL#3:ResetsT/Statsetpointsout4Ffromsetpointandlimitsthechilled water valves to 25% of open capability. 19 Energy Management and Control System:Desired Capabilities and Functionality DEMAND LEVEL # 4: Load sheds / load rolls (often referred to as duty cycling) main chiller or direct expansion A/C unit off. Chiller and fans shall be monitored for allowable off and short cyclingruntimes.Oncereleasedtorun,aunitshallbeallowedtorunapresetamountoftime before cycling off again. Units shall be only allowed to stay off a preset amount of time. Recommendation: Becausethisfunctionisusefultoreducepeakconsumptionand controlloadsbasewide,itisrecommendedwhenthedemand chargeisasignificantpercentofthetotalenergycost(greater than 20%) or other drivers require the ability to shut off or reduce peakenergyusage.Thisfunctionisnotreadilyavailableinmost EMCSsystemsandhastodevelopedandintegratedin-houseor with the help of a third-party service provider. B.Duty Cycling DutycyclingiscyclingofequipmentONorOFFtocontrolthebuildingpeakenergy consumption while still maintaining comfort conditions. Duty cycling is one approach to demand limitingandisameanstochangeorcontrolthedutycycle(i.e.,theratioofon-periodtototal cycle time) of on/off controlled equipment (e.g., unitary air conditioners, heat pumps, furnaces). Thereareanumberofwaystoimplementdutycycling,asdescribedinaFEMPTechnology Focus article3. The following is extracted from the article: Inthepast,avarietyofmethodswereusedtoimplementdutycyclingonheatingandcooling equipment.Theserangedfromsimplefixed-time-basedstrategiestosophisticatedoptimization methods. In all of these methods it is ultimately the off-period that is either fixed or adjusted in either a given reference period (typically 15 or 30 minutes), or dynamically based on temperature measurements. This results in the imposition of an equipment duty cycle that is primarily under the control of the cycler; i.e., it overrides the natural duty cycle of the thermostat. Recommendation: Becausethisfunctionisonlyusefultoreducethepeak consumption, it is only recommended when the demand charge is a significant percentage of the total energy cost (greater than 20%). This function may not be available in most EMCS systems and has to be developed and integrated in-house or with the help of a third-party service provider. C.Event Initiated Controls Eventinitiatedcontrolsaresimilartodemandlimitingcontrolswhereasetofcontrol sequencesareinitiatedwhenacertainexternaleventoccurs.Forexample,ifthefacilityis participatinginanemergencydemandresponseorloadcurtailmentprogramofferedbysome utilities, the utility may send a signal directly to the EMCS or a page to the building operator. If theutilitysendsamessagedirectlytotheEMCS,theactionsareautomaticallyfollowed,while thebuildingoperatorhastoinitiatetheexternaleventifapagernotificationisused.Another exampleisafacilitythatisnormallyunoccupiedexceptforspecialevents(e.g.,agymnasium, lyceum or a sport facility) for which control sequences can be event initiated. 20 Energy Management and Control System:Desired Capabilities and Functionality Recommendation: Becausethisfunctionisonlyusefultoreducepeakenergy consumption, it is only recommended when the demand charge is a significantpercentoftheenergycost(greaterthan20%).This function is not readily available in most EMCS systems and has to bedevelopedandintegratedin-houseorwiththehelpofathird-party service provider. D.Load Shifting Load shifting is another demand-side management process where the load is shifted from peak consumption periods to non-peak periods, usually to take advantage of time-of-use rates or realtimepricing.Itrequiresathoroughanalysisoftheloadsandprocessesthatcanbeshifted and the benefits arising from shifting. Most EMCS systems can be programmed to shift electric loads, but the facility manager or operator must currently perform analysis of what loads to shift andcalculatemanuallyhowlongtheycanbeshifted.Technologyshouldbecomeavailableto automatically support and execute such decisions over the next several years. Recommendation: Becausethisfunctionisonlyusefultoreducethepeakenergy consumption, it is only recommended when the demand charge is a significantpercentofthetotalenergycost(greaterthan20%). ThisfunctionisnotreadilyavailableinmostEMCSsystemsand hastobedevelopedandintegratedin-houseorwiththehelpofa third-party service provider. Advanced Functions Functionsthatfallintheadvancedgroupinclude:optimalsequencingandloadingmultiple Chilled Water Pumps load aggregation, automated remote fault detection and the diagnostics of buildingsystemsandsubsystems,trackingenergyusageandend-usesbybuildingorgroupsof buildings,andwhole-buildingoptimizationandoptimizationacrossmultiplebuildingsand building systems. A.Automated Fault Detection and Diagnostics Effective use of building system diagnostics can help facility managers and operators cut the costofoperationsandreduceconsumptionofresourceswhileimprovingthecomfortandthe safetyoftheoccupants.Continuousdiagnosticsforbuildingsystemsandequipmentwillhelp remedymanyproblemsassociatedwithinefficientoperationofbuildingsbyautomaticallyand continuouslydetectingsystemperformanceproblemsandbringingthemtotheattentionof buildingoperators.Someoftheseproblems(e.g.,simultaneousheatingandcooling)might otherwise go undetected. Advanced diagnostic tools can even suggest causes of problems, make recommendations for solving problems, and estimate the cost of not solving a problem. Althoughfaultdetectionanddiagnosticshavebeenanactiveresearchtopicforseveralyears, onlyafewsoftwareapplicationsareavailabletoday.Lackofawell-definedinfrastructureand 21 Energy Management and Control System:Desired Capabilities and Functionality difficulties in accessing sufficient quantity and quality of data are two of the reasons for the slow start. Control manufacturers have not yet started packaging diagnostic tools with EMCS systems. At the present time, these diagnostic tools have to be used as standalone third-party applications. Recommendation: having automated fault detection and diagnostic capabilities can enhance the operation and maintenance of a facility. Although a number of researchers have been working in this general area, there are not many commercial quality tools available currently. Existing tools should be evaluated and used where possible and additional capabilities should be developed and integrated with the help of a third-party service provider as needed. B.Monitoring Simultaneous Heating and Cooling Simultaneous heating and cooling can occur in a building intentionally or unintentionally. In a multi-zone system, if one of the zones is calling for heating and the rest are calling for cooling, the air to the zone that requires heat will be cooled first and then heated. This generally occurs in systems when cooling is the dominant load and is provided by a central chiller plant. Reheating oftheairusuallyoccursinvariableairvolume(VAV)orconstantairvolume(CAV)terminal boxes,wheretheairtemperatureisbroughttothecorrecttemperaturefordischargeintoeach zone.Thisshouldbeavoidedorminimizedwherepossible.Simultaneousheatingandcooling can also occur because of faulty air-handling unit (AHU) controls or leaky valves. In most cases, suchfaultycontrolscannotandwillnotbedetectedbecausetheydonotleadtooccupant discomfort.Whenaleakyhotwatervalveleakswaterintotheheatingcoil,itincreasesthe cooling load with little or no discomfort to the occupant. If the leak is not severe (less than 50%),itcangoundetectedbecausethecoolingcoilcompensatesfortheleak.Thelogic necessary to detect such faulty operations is not generally provided with EMCS systems. Algorithms are under development for automatically detecting these problems, but they may not be included in EMCS systems for several years. Recommendation: Currently, EMCS systems do not provide for a mechanism to detect simultaneous heating and cooling. Depending on the type and condition of the system, the impact of simultaneous heating and cooling can be significant and difficult to detect. Custom code or third-party tools or algorithms should be seriously considered to mitigate simultaneous heating and cooling from occurring. Managing this function is a requirement of the EMCS specialist, who is responsible for energy usage and the operations of the EMCS system. C.Tracking Energy-Use Although tracking energy use for major equipment and end-uses has several benefits, it is not generally done through an EMCS. Leveraging EMCS infrastructure to track energy consumption of major end-uses can be less expensive than setting up standalone systems to collect the end-use 22 Energy Management and Control System:Desired Capabilities and Functionality consumptiondata4.Thebenefitsofenergyend-usetrackingforafacilitymanagerofalarge campus with distributed facilities include: Abilitytobenchmarkhistorical,normalized(i.e.,withrespecttoweather,size,sales) enduesconsumptionbetweensimilarbuildings/facilities.Comparisonwithbenchmarks can help identify buildings with operational inefficiencies. Ability to forecast energy budgets and prepare energy purchasing plans Ability to track energy savings from performance contracting Ability to detect unscheduled operations of equipment as a result of control malfunction, errant programming or to detect controls that have been manually overridden. This management can normally be accomplished through software resident on an automated meterreadingsystem(AMR),supervisorycontrolanddataacquisition(SCADA)systemor EnergyMonitoringandControlSystem(EMCS).Inallcases,technologyimprovementsand personnel constraints dictate maximum use of remote meter reading. Recommendation: to monitor the energy usage BTU meter, Electricity meter, and Water meters need to be integrated with EMCS / BMS Currently, EMCS systems do not provide a function to track energy use/Energy Bill within equipment or buildings. With software integration of supplied energy meter consumption of energy can be tabulated an alarm can be generated in EMCS/ BMS to intimate the user on excess usage. D.Whole-Building Optimization Inthederegulatedutilityenvironment,oneofthegreatestcost-savingsopportunitiesfor facilitymanagersandoperatorsliesintheabilitytocontrolandoptimizewhole-facilityenergy consumption.Someutilitiesarenowofferingratesthatvarybyhour-of-dayandday-of-week, similartothereal-timepricingratesandtime-of-useratesofferedbysomeutilities.Totake advantage of time-varying rates, facilities will need advanced control strategies. These strategies includeHVACloadsheddingforchillers,thermalstorage,supplyandzonetemperatures,fans, and pumps; load shifting, using pre-cooling or thermal storage; and fuel shifting for gas, oil, and standbygenerators.Thesestrategiesnotonlyrequiremonitoringtheperformanceofequipment and accessing data from sensors and meters but also the capability of controlling equipment from a central location. In regulated areas, in addition to the energy charge, most utilities also have a demand charge that can be as high as $25 per kW or more. In some cases, the peak period is tied totheutility'ssystem-widepeak.Insuchacase,predictingthesystem-widepeakand implementing the load control measures during a 2 or 3 hour window surrounding the anticipated time of the peak will save a large facility (such as a University Campus) a significant amount in demandcharges.Suchadvancedcontrolandcampuswideoptimizationtoolsarestillintheir infancies, so the EMCS vendors are unlikely to provide them in the near future. 23 Energy Management and Control System:Desired Capabilities and Functionality Recommendation: Currently,EMCSsystemsdonotprovidethisfunctionality,andit isunlikelythattheywoulddothisinthenearfuture.Theneedof this function should be evaluated on a site-by-site basis because it requires a significant in-house or third-party development effort. E.Whole-Site Optimization, Integration plus Security Inthecurrentinformationtechnology(IT)environmentmanycomputerizedsystemsarebeing advertised to directly connect to the facility local area network (LAN). This is true of all EMCS systems. Several issues have to be addressed before connecting an EMCS system to a LAN. SecurityoftheLANisprimary.IfconnectingtoanopenbaseLANsystem,thebaseIT operations staff will have security requirements that will need to be addressed and followed. Access to the EMCS system will be restricted to these facility LAN requirements. Most of these willhavetodowithoutsideworldconnectionslikemodems,Internetaccessandtypesof softwarerunningonconnectedcomputers.MostfrontendsforEMCSsystemswillrunon WindowsplatformsorWindows-basedoperatingsystems.Theequipmentinthefieldnormally willhaveasmallvendoroperatingsystemandisgenerallynotsubjecttoattackfromnormal outsidemeans.Frontendswillhavetobehardenedagainstattackswithfirewallsandvirus protection software. Because most viruses and disruptions come in via email functions, it is not recommended that email accounts and EMCS software be operational on the same critical front endcomputers.Alarmsandbase-widecontrolschemesarecriticaltooperationsofacomplete EMCS system.If the LAN is being overloaded for any reason, these alarms may not make it to their intended recipient in a timely manner. This can be another drawback of having the EMCS on a baseLAN system. Phone-in ability is a verygood maintenance tool for the support of any EMCSsystem.Dependingonsoftware,encryptionandaccessrequirements,theseconnections can be setup for remote, outside service from vendors or base personnel. Recommendation: It is recommended that base EMCS systems be connected to an independent LAN on the base. This can be either a true standalone network or a logical network that isolates it from other network problems and outages. If the system is on a standalone network, then phone-in support becomes a much easier and secure option to implement. A standalone network also opens up the possibility of web access. 24 Energy Management and Control System:Desired Capabilities and Functionality Cost vs. Benefits It is difficult to talk cost vs. benefits, in general terms, because there are many issues that needtobeconsidered.Thissectionwilldiscussthecostbenefitsofdifferentoperational schemes, and savings calculation methodologies. It includes a definition of terms. Basicsavingsrulesofthumb:BecausesomeEMCSfunctionsareonlyusefultoreducepeak consumption,itisonlyrecommendedtoaddthesefunctionswhenthedemandchargeisa significantpercentoftheenergycost(greaterthan20%).Engineeringevaluationsmayprovide anexceptiontothis.Thecoolingenergysavingsfromtheuseofaneconomizercycleranged from 15% to 50%, the precise savings depending on the type of economizer cycle employed and the climate location. Savings from resetting supply chilled-water temperature can range from 5% to 20% (2003 Handbook for HVAC Applications, Chapter 41). Example savings calculation methodology: Afteranextensiveevaluationoftheexamplefacilitysenergyusagereports,energybills,and other square footage sources, the following can be calculated from the data: Based on the start of the example EMCS Project, FY2000 was used as the baseline year. Facility housing costs were not included. The best indicator of energy usage is Btus per square foot per degree-day. This is because the example facility is in constant flux on energy cost, demand charges and even changes in square footage. Energy use per square foot went down from 30.22 averagesBtu/sqft/dd in the baseyear to 24.49Btu/sqft/dd in 2002. This is a reduction of 5.72 Btu/sqft/dd or 18.9% reduction from the base year. This can be attributed to EMCS and other energy conservation measures. There was a square footage increase from the baselineyear of 2305 K square feet in 2000 to 2727 K square feetin2002,anincreaseof15.5%.Usingastraightratioforenergydemand,thismeansthe example facility would have normally had an increase in energy use of 15.5% over this period if it had not been for the energy reduction measures taken. 25 Energy Management and Control System:Desired Capabilities and Functionality Puttingadollarvaluetothisreductionismuchmoredifficultbecauseofprice fluctuationsfrommonthtomonth.Usingcostaveragingforthebaseyearandthecurrenttotal cost per mBtu for the current year to calculate real savings, the numbers are as indicated below. Savings are calculated from reduction x dollars per Btu for that year Z square footage (reduced x $/Btu/Zsq ft). Todate,thisamountsto$1.3milliondollarsinaccumulatedsavingsfrombaseyearof avoidedcostinenergyonly.Nocredithasbeentakenforlaborsavings.Thesystemhasonly been in operation for 2 full years, thus 2001 and 2002 are the only years that show savings. 26 Energy Management and Control System:Desired Capabilities and Functionality Commissioning EMCS Without complete and through commissioning of the EMCS, there is no guarantee that the functions and capabilities will work as intended. Most often even the new systems are not adequately commissioned leading to incomplete and inefficient operation of the EMCS. Sufficient resources should be allocated to commission the EMCS after it is installed to ensure that it works as intended. Often during installation, key pieces of hardware are either missing, not installed, or defective. Other common problems include 1. The installation of sensors and thermostats in the wrong locations, and or 2. Improper coding of the sequence of controls for equipment. These and other problems are identified and corrected by a good control system commissioning process. Recommendation: We recommend that control system specifications require a thorough commissioning of EMCS as part of EMCS procurement and that technicians on-site with end ownership verify same. 27 Energy Management and Control System:Desired Capabilities and Functionality Operator Skills and Training One of the keys to enhancing building operations and maintenance and thereby achieving the efficiency goals of buildings/facilities are well trained building operators and managers. Lack of properly trained operators and high turnover of building operators contributes significantly to inefficientbuildingoperationandmaintenance.Performanceproblemsresultfromerrorsin installationandoperationofcomplexbuildingheating/coolingsystemsandparticularlytheir controls.Furthermore,HVACsystemsarebecomingincreasinglymoresophisticatedtoobtain ever-higherlevelsofenergyefficiency,addingtothecomplexityandsubtletyofproblemsthat reducethenetefficiencyacquired.Withouttherightskillsetsandpropertraining,building operatorsandmanagersmaynotbeabletomanagethefacilityoptimallyevenwiththemost advancedEMCS.Tooperatebuildingsefficiently,inadditiontoagoodcontrolsinfrastructure, the following is also necessary: 1.Increase the skill level of operators and maintenance personnel. This can be accomplished by providing the building operators with frequent proper training and incentives for performing well. 2.Provide adequate engineering supervision of technician work to ensure that adequate knowledge of fundamental processes is brought to bear on operation and maintenance actions. 3.Provide operators with system performance feedback. This includes not just reporting alarms through an EMCS, but also providing easy-to-use system diagnostic information to correct problems and to understand the cost impacts from improper operations. 4.Provide incentives for correcting problems. There is a general lack of motivation among operators to identify the root cause when a problem arises. More often operators try to correct the symptom of the problem by changing set points or controls rather than determining the root cause and correcting it. 5.Provide incentives for achieving efficiency goals. Most often when building operators work hard to achieve the efficiency goal set for the building; they are rewarded with a reduced energy budget corresponding to the new lower consumption level. This budget reduction may be interpreted by engineering and operations staff as a disincentive. Attention should be given, instead, to ensuring that operators are provided positive reinforcement for good performance. 6.Educate everyone who influences the planning, budget, design, and procurement of energy and related systems. 28 Energy Management and Control System:Desired Capabilities and Functionality Control-System Maintenance Maintenance of the control system is critical to ensuring its performance after installation and commissioning. Commissioning ensures that the control system operates properly at only one point in time, the time immediately following the completion of commissioning. Many factors can cause degradation of the control systems performance afterward: Overrides of automatic control by operations staff, a frequent problem, generally driven by customer complaints Drift or failure of sensors Failure of actuators Corroded or failed wires and their connections Improper changes to control schedules (sometimes temporary changes become permanent changes by oversight) Degradation or failure of controlled devices. These problems can only be prevented by good operation and maintenance practices, such as a reporting system for all overrides, periodic re-commissioning of the control system, and maintenance of the control system and the physical components it actuates. As cited earlier in this document, automated fault detection and diagnostic tools, alarms, plots of trend data, and maintenance tracking systems can be used to help with identifying performance degradation, faults and the need for maintenance, but even these tools cannot ensure that the control system continues to operate properly unless the maintenance staff heeds the results and recommendations of these tools and takes action. Recommendation: Werecommendthatthecontrolsystemspecificationsinclude requirements for maintenance documents and a maintenance plan. Furthermore,thefacilityshouldalsoconsidercontractingfor maintenancesupportifitwillnotbeprovidedin-house.In procuringmaintenancesupport,theorganizationshouldensure that the maintenance contract requires maintenance of all systems in a manner that ensures continuous, or nearly continuous proper operationofallcontrolsandcontrolleddevices.Thisrequires frequent,periodicinspection,testing,andevaluationofsystems andequipmentfollowedbythecorrectionofanydefectsfound. Systeminspection,testingandevaluationcanbeautomatedvia continuous monitoring tools. TAB-B Advantages of Variable Frequency Drive in Energy Management and Control System Advantages of Variable Frequency Drive in Energy Management and Control System: Project Name: New College Of EngineeringQatar University State of Qatar Client:Qatar UniversityState of Qatar Project Consultant: Kathib & AlamiPO Box No 10281Doha Qatar Main Contractor: AL Darwish Engineering WLLPO Box No 183Doha Qatar MEP Contractor: ETA StarDoha Qatar Prepared for Project:Prepared By: New College Of EngineeringShahjan Trading Company W.L.L Qatar UniversityPO Box 8689 State of QatarDoha Qatar Variable-Speed Drives: An Energy-Efficient Solution Among the most successful strategies managers have at their disposal for controlling electrical energy use and minimizing utility costs is the use of variable-speed drives (VSDs). Incorporating VSDs into applications such as fans, pumps, and cooling towers can reduce energy use up to 50 percent at partial loads by matching motor speed to the changing load and system requirements. Advances in VSD technology are putting even more power in the hands of maintenance and engineering managers, who are taking a closer look at the life-cycle costs and potential benefits of VSD applications for their facilities. Technology Drives Forward Electric motors driving equipment, such as pumps and fans, normally operate at a constant speed. Some form of mechanical throttling a valve on the outlet, in the case of a pump, or the slats in a louver, in the case of a fan controlled the water or airflow speed and volume. Using these flow-control methods, the motor continues to operate at full speed and uses electric energy at the full-load rate, even though it was performing less useful work. In the process, it wasted a great deal of energy. VSDs have introduced a more efficient way to provide load control when the load varies, which is most of the time when moving fluids. The two most commonly used methods to vary speed electrically, rather than mechanically, depend on whether the drive is alternating current (AC) or direct current (DC). If it is AC, which encompasses most motors, varying the frequency of the electrical energy supplied to the motor controls the speed. Examples include AC motors driving fans, pumps, and compressors. If the motor is DC still a large portion of equipment-drive motors a typical solution is to apply an AC power source to a silicon-controlled rectifier (SCR) motor control, converting the AC to rectified DC. DC power, speed, torque and horsepower then vary to meet the demand. Technicians can convert AC induction motors to variable-speed applications by inserting a variable-frequency drive (VFD) controller basically, a power supply and a computer into the circuit, either as the original equipment specification or as an upgrade, matching the controller and motor with demand variations required by the application. Two AC motor principles form the basis for the significant efficiency gains VFDs offer. First, speed varies directly with frequency. Second, input power varies with the cube of the speed and volume. The speed principle states the speed at which an AC electric motor rotates depends on the number of poles in the motor and the AC frequency. Changing the frequency changes the speed. This relationship is expressed mathematically as follows: Speed in revolutions per minute (rpm) equals the frequency multiplied by 120, with the product divided by the number of poles, where the constant, 120, is 60 seconds per minute multiplied by two poles per pole pair, and frequency is expressed in cycles per second. Based on this equation, a four-pole AC motor running at 1,800 rpm under 60 Hertz (Hz) power would run at 1,500 rpm if the frequency were reduced to 50 Hz. Because of advances in VFD technology, most units now use pulse-width modulation (PWM) as the basis for their circuitry. A PWM control converts the 60-cycle input line power to DC, then intermittently and rapidly applies the output voltage for varying lengths of time, similar to AC, to arrive at the desired frequency. The power principle above states the power required to drive a pump or fan varies with the cube of fan or pump speed and volume. Based on this principle, only slightly more than 10 percent of the power required at full speed is required to turn a pump or fan at one-half speed. Compared to other ways of controlling partial loads, VFD advances have yielded savings in the form of energy reduction that often reach 50 percent. Multiplying Applications Advances in technology have produced a proliferation of application-specific features. In HVAC applications, VSDs are integrated with building automation system protocols. Most VFDs now use the latest advances in soft switching, such as fourth-generation insulated-gate bipolar transistors (IGBT). These latest-generation IGBTs cause less stress on insulation, increasing motor life. Advantages for HVAC variable-torque applications include more low-speed torque applications, motors that operate with less harmonic noise, and better low-speed stability with minimum oscillations. They also feature better operator interface features, including: start, stop and speed adjustment reversing and toggling between manual and automatic speed adjustment from an external process control signal alpha-numeric display, indicator lights, and meters to provide text information for communication and maintenance a front-mounted or cable-connected keypad for input input/output terminals available for push buttons, switches and other interface devices serial communication port for VFD configuring, monitoring and controlling using a computer loading of parameter settings from one drive to another multi-day timers broadcast function to control dozens of drives from one advanced operator panel. Operational capabilities include lowering the peak energy use on which energy rates are based. Normally, when an AC motor starts, it draws an inrush of as much as 300 percent of rated current while developing only 50 percent of rated torque. When a VFD starts a motor, it applies a very low frequency and very low voltage to the motor, gradually ramping up the frequency and voltage at a controlled rate. This approach allows the motor to develop 150 percent torque while drawing only 50 percent of rated current. For quicker stopping, operators can add a braking circuit to produce the required braking torque. Available VFDs can match the voltage and current of most three-phase AC motors. Low-voltage controllers range from 110 volts to 690 volts (V) and from 0.2 kW or horsepower (hp) to 750 kW or 1,000 hp. Medium-voltage controllers operate at 2,400/4,160 V and 60 Hz, or 3,000 V and 50 Hz, and on up to 10 kilovolts. With the availability of premium motors, operators can extend VFD-to-motor cable lengths up to 190 percent of the distance allowed with energy-efficient and standard motors. Application Costs and Benefits Experts estimate that 50 percent of the energy supplied in the United States powers AC induction motors. Of that amount, 65 percent goes for variable-speed applications. So the energy-reduction opportunities offered in this area alone are tremendous. Among the many other benefits of VSDs are less wear on equipment, lower maintenance costs, and a lower power factor (PF), which is the ratio between active power and total power. Taken together, these benefits lower both the rate charged per kW hour by the utility company and the total kW hours required. Energy costs can drop by as much as 50 percent when the connected loads are below rated capacity because at lower speed, the drive uses less power, rather than dissipating it as heat or other losses. Equipment wear will slow, and equipment life cycles will lengthen, due to less stress on rotating parts, including bearings, sleeves, casing wear rings, couplings, and packing glands, as well as on electrical parts, such as windings and insulation. Also, fewer vibration problems related to throttling will arise to drive up maintenance costs. A side benefit of the AC VSD is it will correct the PF without using expensive capacitors on all induction motor circuits converted to VSD. Induction motors generally have low PF around 0.85, where ideally PF equals 1, meaning 100 percent useful or active power and no losses or reactive power. So, in addition to the energy savings from running at speed adjusted to need, there also are savings associated with reducing the use of reactive power. The Payoff Managers can quickly and accurately calculate the payback on the purchase price, breakeven point, and return on the investment using available energy-savings programs. Location-specific data, such as VSD conversion purchase price, flow rate and head, daily and annual flow variability, operating shifts, and annual operating days are the input. The output is the amount of time, often as little as a few months, for the investment to pay off and start generating net savings. Added to these benefits are purchase-price rebates from utility companies in some instances as high as 50 percent, depending on the size of the drive and application. Utilities know demand on their systems will drop substantially with the installation of VSDs. Managers might need pre-approval, so due diligence in this regard is important. Energy-saving benefits versus acquisition and operating costs are certainly worth the effort. Finally, most drives are subject to deterioration in dry and wet conditions, similar to other motors. Still, some suppliers predict the mean time between failures will be as high as 200,000 hours or more with only very basic preventive maintenance for example, cleaning, visual and infrared inspection, and tightening on weekly to monthly cycles, depending on severity of conditions and use. Theoretical Analysis of Energy Saving by Use of VFD Variable frequency drives compared to throttling devices In many flow applications, a mechanical throttling device is used to limit flow. Although this is an effective means of control, it wastes mechanical and electrical energy. Figure 1 represents a pumping system using a mechanical throttling valve and the same system using a VFD. If a throttling device is employed to control flow, energy usage is shown as the upper curve in Figure 2, while the lower curve demonstrates energy usage when using a VFD. Because a VFD alters the frequency of an AC motor, speed, flow, and energy consumption are reduced in the system. The energy saved is represented by the green shaded area. Variable frequency drives theory The affinity laws can determine the system performance for centrifugal devices, including theoretical load requirements and potential energy savings. Represented in Figure 3 are the three affinity laws: 1.Flow or volume varies linearly with speed. If speed decreases by 50%, flow decreases by 50% (Graph A). 2.Pressure or head varies as a square of the speed. If speed decreases by 50%, the pressure decreases to 25% (Graph B). 3.Power or energy consumption varies as a cube of the speed. If speed decreases by 50%, power consumption decreases to 12.5% (Graph C). The potential of energy savings is available as the flow requirement is reduced. Pumping system characteristics Determining the system curve, which describes what flow will occur given a specific pressure, is critical to selecting the appropriate pump for a system. To determine an accurate system curve, two elements must be known: Static head or liftthe height that the fluid must be lifted from the source to the outlet. Friction headthe power required to overcome the losses caused by the flow of fluid in the piping, valves, bends, and any other devices in the piping. These losses are completely flow-dependent and are nonlinear. In Figure 4, the static head, friction head, and resulting system curve are shown for a typical pumping system. In this example, the maximum flow rate required is 160 gallons per minute (gpm).This information helps to determine the required pump and impeller size for the system to provide the maximum required flow. Based on the system curve in Figure 4, the pump should develop at least 120 feet of pressure. Variable frequency drives for further cost savings The use of VFDs can bring further total system cost reductions, due to the elimination of components required for valve control only. In a valve flow control system, there are losses in the valve and additional piping required to bring the valve to a height where it can be adjusted. In the previous example, the piping loss is 10 hp, and the valve loss is 15 hp. Because of these losses and the internal pump loss, to obtain a head equivalent to 50 hp, an equivalent of a 90 hp pump and a 100 hp motor is required. With the use of the VFD, there are no valve or pipe losses due to bends or additional piping, thus reducing the piping losses to 8 hp. With the reduction of these losses, a smaller pump can be used with lower losses. For the same equivalent of 50 hp of head, only a 68 hp pump and a 75 hp motor are required. This results in a substantial system cost and installation savings, further economically justifying the use of the VFD. BTU Meter Why Measure Thermal Energy?To control something, you must first measure it BTU Meters are used to monitor the consumption of energy in chilled water line What is BTU Heat Metering? In almost all Cooling applications chilled water is used. One is interested in knowing the amount of energy extracted from the cooling media and not the flow rate. This involves the measurement of flow of the cooling medium, the inlet and outlet temperature and then using temperature difference to calculate the Net Heat transferred.British Thermal Unit (BTU) meters use accurately calibrated ultrasonic Flowmeter, Matched pair of temperature sensors and computing unit to calculate Net Heat consumed. Net Heat = Qm X Enthalpy Difference (HT1 HT2) Special Features Single source for flowmeters, temperature sensors and net heat computing unit The NHM system uses most accurate type of electromagnetic flowmeters for the measurement of flow All the flowmeters factory calibrated to ascertain highest accuracy over longer period of time Matched pair of accurately calibrated Temperature transmitters User defined flow units for the flowmeter Flowmeters display instantaneous and totalized flow User defined (Factory set) units for the Net Heat computing units Nonvolatile memory stores the data in case of power failures BTU Metering Benefits / Results Utilities Cost Allocation Utility consumption baseline can be decided Central Utilities Growth Planning Promote ConservationAcquire LEED points Energy usage in Operational hour & Non Operational hour can be determined and tabulated. Excess usage can be highlighted to client / User to reduce energy consumption TAB-C Energy Management PresentationUSE OF BUILDING MANAGEMENT SYSTEMIN ENERGY MANAGEMENTFor COLLEGE OF ENGINEERING PROJECT @ QATAR UNIVERSITY PROPOSED BMS FOR COE PROJECTSmartStruxure solution Integrated building management systemSmartStruxure solution Real simple. Real Smart. Real Performance.Your job is complicated SmartStruxure solution helps you simplify by delivering the right information when, where, and how you want it.> Personalized user interface> Anytime, anywhere access> Simplified day-to-day operationsSmartStruxure solution delivers an efficient enterprise by optimizing your buildings performance and saving up to 30% or more of your energy costs.> Optimized performance> Maintain facility comfort and increase value> Actionable intelligenceEQUIPMENT'S ON BMS a. Following listed Equipment's of this Building has BMS Connectivity. Some of them are only monitored by BMSEquipment's On BMS Ref: STC/IO2014/J11079/COE/ETA/Rev-01EXHAUST FANS28 Nos JET FANS7 Nos AHU (Arrangement-02) 34 NoFRESH AIR FANS5 Nos LIGHTING CONTACTS 323 Nos CHILLED WATER SYSTEM CHILLED WATER PUMPSCHP-01 to CHP-044 NosMAIN LOAD1 No EXPANSION TANK1 No TREATMENT PLANT 1 No FAHU (Arrangement-01) 9 NoKITCHEN HOOD EXHAUST FAN 1 No CRAC UNITS4 No OIL/GREASE INTERCEPTORS UNIT7 NoFM-200 1 NoGAS (LPG) SYSTEM1 No WATER FEATURE - 1 FILTERING SYSTEM (MCC) 5 No WATER FEATURE - 1 FILTERING SYSTEM (MCC) 7 No LIFT17 No TRANSFORMERS9 NosEMERGENCY GENERATOR1 No MAIN FUEL TANK1 No DAY TANK2 No FUEL PUMP 2 No MVSG: 7 No DATA AND TELEPHONY 1 No PUBLIC ADDRESS1 No CC-TV STYSTEM 1 No MASTER CLOCK SYSTEM 1 No IINV TANK 1 No TREATED WATER BOOSTER PUMPBP-4,BP-5,BP-6 1 Set GRAY WATER BOOSTER PUMP & TANKS1 Set IRRIGATIONWATER BOOSTER PUMP & Tanks1 Set HOT WATER RE-CIRCULATION PUMPCP-1,CP-2,CP-3,CP-4 2 Set SUBMERSIBLE PUMP 13 Set FIRE PROTECTION WATER TANK 3 No ELECTRIC FIRE PUMP 1 No DIESEL FIRE PUMP 1 No JOCKEY PUMP 1 No DOMESTICWATER BOOSTER PUMP & TANK1 SetFAHU (Arrangement-03) 10 No SMOKE EXHAUSTFANS (SMF-R-01)(SMF-R-01) 2 Nos SMOKE EXHAUSTFANS (SMF-R-01)(SMF-R-01) 2 Nos SMOKE EXHAUSTFANS (SMF-R-01)(SMF-R-01) 2 Nos FAHU (Arrangement-04) 2 NoEMERGENCY GENERATOR1 No FCU 455 Nos Third Paty Integration WATER LEAK DETECTION SYSTEM1 LOT VARIABLE FREQUENCY DRIVES1LOT MCC PANELS1LOT SMDB/ESMDB & EMDB67LOT FIRE ALARM CONTROL PANEL1 LOTDescription Qty UnitMonitorControlCollege Of Engineering Qatar University QatarDate: 27/10/14Rev-0181%6%2%2%0%8%1% 0%HVAC EQUIPMENTS IN BMS FCU (81%) AHU (5.8%)FAHU TYP (01) (2%) FAHU TYP (03) (2%)FAHU TYP (04) (1 %) Ventillation Fans (8%)CRAC UNIT(2 %) Chilled Water System (1%)95%2%1%2%3%ELECTRICAL EQUIPMENTS IN BMS Intgerated Lighting Control CircuitsTRANSFORMERSEMERGENCY GENERATORMVSG:02468101214Data & TelephonePA SystemCC-TV SystemMaster ClockIINV TANKBooster PumpGreay Water SystemIrrigation Water SystemHot water Circulation SystemSubmersible PumpsFire Fighting SystemDomestic Water SystemWater Leak DetectionFire Alarm IntegrationUPS SystemCentral BatteryGenerator IntegrationOther Service Other ServiceEnergy Management Features 1. Energy Management Features (As per Specification)2.11 ENERGY MANAGEMENT FEATURESA. Energy Manager1. Provide a supervisory routine, which shall improve the energy efficiency of the building HVAC systems. This feature shall oversee the execution of all Energy Management features as function as an executive software system for them. That is, it shall establish priorities and execution times for all of the energy related features (Load Manager, HVAC Manager, Chiller Manager). B. Load Manager1. The Load Manager (LM) feature shall provide a means to reduce electrical energy usage. Thecontrol algorithms shall be designed for use with electrical energy control, but applications to other energy sources shall be possible without software revisions.2. The Load Manager feature shall be controlled and serviced by the Energy Manager, the supervisory program that coordinates the activities of all energy application features. The Load Manager shall be a supervisory program overseeing the functions of Demand Limiting. TheLoad Manager shall be provided to support either Imperial or Metric units of measurement.3. Each Load Manager system shall be assigned a unique identifier and expanded identifier as specified herein before under SYSTEM FORMAT. The unique identifier shall be used to request operator relevant data pertinent to Load status. The expanded identifier shall be used to further identify or label the LM system. A minimum of 32 LM system shall be able to be defined 4. Load Manager systems, points and parameters shall be defined on-line by the user. Any additions, modifications or deletions shall be made on-line.a. Demand Limiting/Load Shed during emergency power supply All equipment is connected to power supply mains in a flexible way to run all equipment during emergency power supply. The BMS will take the necessary action to manage power consumption during supply failure in the optimum way. The BMS will shed the equipments with lower priorities to give priority for equipments with higher priorities and based on a pre-defined priority assignment. The BMS will continuously monitor the load on the emergency generator to make sure that no overload occurs.1. Fire Mode:During fire mode, the following equipment shall have the priority to operate:Fire pumps.Smoke fans and related dampers.Toilet and kitchen exhaust fans.Emergency lighting.Economizer fans.Computer room cooling equipment.2. Normal Power Failure ModeDuring normal power failure, -with no fire mode the following equipment shall run using emergency power from Diesel Generator:(I) Computer room cooling equipment.(ii) Toilet and kitchen exhaust fans.(iii) Emergency lighting.(iv) Booster and sump pumps.(v) LiftsC. HVAC Manager1. The HVAC Manager feature shall be controlled and serviced by the Energy Manager, the supervisory program that coordinates the activities of all energy application features. The HVAC Manager shall be a supervisory program overseeing the functions of Optimal Run Time, Supply Air Reset and Enthalpy Switchover.2. Each HVAC Manager system shall be assigned a unique identifier and expanded identifier as specified herein before under SYSTEM FORMAT. The unique identifier shall be used to request operator relevant data pertinent to HVAC status. The expanded identifier shall be used to further identify or label the HM system. The whole Projects HVAC systems shallbe able to be defined3. HVAC Manager systems, points and parameters shall be defined on-line by the user. Any additions, modifications or deletions shall be made on-linea. Optimal Run Time (Optimal Start/Stop)(I) The Optimal Run Time (ORT) program shall control the start-up andshutdown times of HVAC equipment during both the heating and cooling seasons to provide the most efficient operating strategy during potentially energy wasteful periods of the day. The ORT program shall base its control decisions primarily upon occupancy schedules, outside air temperature, seasonal requirements, and interior roommass temperature of the building.(ii) For start-up, ORT program shall use outside air temperature and room mass temperatures to "learn" the building's thermal characteristics through an adaptive modeling technique. The adaptive model shall allow the system to predict how long the building shall take to warm-up (heating mode) or cool-down (cooling mode) under different outside and inside temperature conditions(iii) For shutdown, ORT program shall use the outside air temperature and the building thermal characteristics to determine how early it can shutdown the system without adversely affecting ventilation requirements(iv) The ORT program shall analyze multiple building sensors to automatically determine the seasonal mode and worst-case condition for every day of the year(v) Analysis shall require only easily obtained occupancy schedule data and desired mass temperatures for implementation.b. Duty Cycling(I) The Duty Cycling (DC) program shall cycle the HVAC equipment On/Off during both the heating and cooling seasons to provide the most efficient operating strategy during potentially energy wasteful periods of the day and conserving electrical energy. The DC program shall base its control decisions primarily upon interior room mass temperature of the building and configurable Hi and Lo limits.(ii) The DC program will calculate Off times to provide minimum energy consumption(iii) The temperature sensor monitors each area affected by the duty cycling. If feedback from the sensor indicates that the area is within comfort range, duty cycling takes place.(iv) If temperature approaches the limits of the comfort range, the OFF cycle is reduced.(v) Each price of equipment assigned to duty cycling will be assigned a minimum and a maximum OFF times. A Minimum OFF time ensures that the equipment is protected from damage due to short cycling. MaximumOFF time guarantees that equipment is brought back into use before space control is jeopardizedc. Chiller Log/Alarm: Provide print out of all variables/alarm measured/detected by chillers computers. The measured variables output shall be hourly chiller log for 24 hours between 15th and 22nd J uly every year and then on single 24 hours print on the 15th day of each month. However, all data from chillers computers shall be stored on the computer hard disk in work sheet format for each hour of the 24 hours. The Contractor shall provide all wiring from chiller interface box to BMS and shall obtain chiller's manufacturers complete data for the worksheet report.D. Chiller Manager1. The Chiller Manager (CM) feature shall be controlled and serviced by the Energy Manager, the supervisory program that coordinates the activities of all energy application features. The Chiller Manager shall be a supervisory program overseeing the functions of Chilled Water Temperature Reset and Chiller sequencing. The Chiller Manager shall be provided to support either Imperial or Metric units of measurement.2. Each Chiller Manager system shall be assigned a unique identifier and expanded identifier as specified herein before under SYSTEM FORMAT. The unique identifier shall be used to request operator relevant data pertinent to Chiller status. The expanded identifier shall be usedfurther identify or label the CM system. A minimum of 32 CM systems shall be able to be defined.3. Chiller Manager systems, points and parameters shall be defined on-line by the user. Any additions, modifications or deletions shall be made on-line.a. Chilled Water Reset: Chilled Water Reset (CHR) program shall be provided to automatically reset the chilled water temperature to the highest possible value, which will still satisfy the cooling coil requiring the greatest cooling.b. Chillers (Boilers) Lead/Lag Sequence:1. Chiller (Boilers) Lead/Lag Sequence (CBLLS) shall be provided to automatically control chillers sequence of operations as well as chillersassociated pumps. The sequence will cycle the chillers on/off based on the chilled water load to provide minimum energy consumption and increase mechanical equipments (Chillers and Chilled Water Pumps) life cycle.2. The sequence will use the main return chilled water temperature as a load indication to calculate chillers requirements. T1 will be the temperature at which Chiller#1 will have to be started, T2 will be the temperature at which two chillers must be started and finally, T3 will be the temperature at which the three chillers must be started. A configurable minimum Start/Stop time period will be used by the sequence to prevent successive starts and stops in case the load cycles within the boundaries of on of the limiting temperatures (T1, T2 & T3).3. The sequence will also make sure to start the standby chillers in case any chiller fails to start.4. The sequence will also keep track of the totaled start period for each individual chiller. The sequence will, and based on these values exchange the chillers starting order to reach an approximately equal. usage period for all chillersc. Condensed Water sequence1. The Condensed Water Sequence (Cooling Towers Sequence), (CTS) will manage the operation of the cooling towers, cooling towers fans speeds as well as the condensed water circuit and associated condensed water circuit pumps. The sequence will cycle the towers fans speed1/speed2/off based on the condensed water load to provide minimum energy consumption andincrease mechanical equipments (towers, chillers and condensed water pumps) life cycle2. The sequence will use the main return condensed water temperature as a load indication to calculate cooling towers requirements. A condition which must always be satisfied is if the one chiller is started, at least two CTs must be started, if two chillers are started, at least three CTs must be started, if the three chillers are started, all the cooling towers must be started.3. A second control factor is the two speeds fan motors used to reduce energy usage in case of part load4. Configurable minimum Start/Stop time period will be used by the sequence to prevent successive starts and stops in case the load cycles within the boundaries of the limiting temperatures.5. The sequence will also keep track of the totaled start period for each individual CT. The sequence will, and based on these values exchange the CTs starting order to reach an approximately equal usage period for all CTs.d. Condensed Water Anti-Surge Protection ValveThe condensed water anti-surge protection valve sequence (ASP), will continuously monitor the temperature of the cooling towers discharge water header, to keep the temperature of the condensers input above a minimum limit. If the temperature of the cooling towers discharge water header is detected below the limit, the ASP sequence will automatically respond and modulate the anti-surge bypass valve correspondingly to keep the temperature above the limit. The ASP sequence will mainly be useful in part load where the cooling towers discharge water temperature will decrease and anti-surge bypass valve will mix a part of the cooling towers supply water with the cooling towers discharge water to attain the required temperature.e. Secondary Pumps Lead/Lag Sequence (SPLL)1. The secondary pumps lead/lag sequence (SPLL) will manage the operation of the secondary pumps. The sequence will cycle the pumps start/stop based on the secondary supply water to provide minimum energy consumption and increase mechanical life cycle.2. The sequence will also keep track of the totaled running period for each individual pump.2.12 PROGRAMMING APPLICATION FEATURESA. Trend Log1. A program shall be provided which outputs a log on a time interval basis. This programshall provide the operator with the ability to place a total of 48 points on four individual Trend Logs and the ability to assign the trend interval from 1-120 minutes.2. The operator shall be able to store up to 19 time intervals of each Trend Log before printing.3. Adding, changing or deleting a trend point, assigning the Trend Log period, or outputtingthe Trend Log shall be performed without any loss of change of-state reporting on the designated hardcopy device.4. Trend Log report information shall be listed in vertical columns. Staggered columns are not acceptable.5. The initiator's name shall appear in the heading of the Trend Log as well as a directory of columnar placement6. Applicationa. Weather DataProcess signals from the outdoor temperature and relative humidity sensors installed in the fresh air intake of one AHU. Using the psychometric calculation program, calculate the wet bulb, dew point temperature and enthalpy. Provide trend log, on one hour interval, for dry bulb, wet bulb, relative humidity, dewpoint and enthalpy. Provide percent clearness factor as detected byb. Central Equipment Energy Use Provide trend log, on one hour interval, for the following:(I) Total building load (tons of refrigeration).(ii) AHU load.(iii) Chilled