b"Integrating P tovoltaics Onto Buildingvelope S ces ho En urfaContinued from page 13 If the roof isfor aarray, get an existing roof plan of the build C Information Requirement for Esuitablesolarontractorsstimating ing or be prepared to create an accurate plan with allHVAC, electric,Provide installation contractor(s) with the following information so they curbs, drains, and scuppers. All of these items must be pinpointed and measured.can price out the systems.Approved roof plan and roof specifications. Roof Approved PV array plan and specifications. Plan The building's orientation, solar shad and insolation are important App wiring plan and specifications. owing,roved design elements useddetermine what type of PVmused and Approved controller plan and specifications (battery systems only). tosyste can be how large of a P caninstalled.alar array performs depends Approved inverter plan and specifications. VarraybeHowsoon location and de .same 100-kW system designed for San J ,Utility-interactive system design. sign TheoseCA, might o y75 kW just adistance away inFrancisco,Photovoltaic estimating software isfrom severalrces.ut nl generateshortSanavailablesou InpCA, due to the differences in theirall data into software and generate the PV system cost. Andy Black's Onclimates.Grid roo rains,twareoneest.softwa Create af plan with all rooftop elements (d curbs, pipes, etc.).sof system isof the b There provides all the financialGoogle or equivalentllite photos of building and surrou ing build- in needed to explainfollowing: sate nd formationthe ings. System cost.Building site location. Operating cost.Building solar orientation (what d faces). Operating pirection itrofits.Identify shadow obstacles (rooftop equipment, surrounding roofs,Operating losses. buildings, and trees can affect the overall effectiveness ofPV system). Netrings. thepowe savIdentify solar access (insolation). lnsolation is aof solar radiation Lifecycle power savings. measure incident on ar Itthe amount of solar energy received over a given T credits. su face.isax area in atime. Capital depreciation. given Ceiling sp and wall structure access for wiring system to the utilityRebates. ace service.Return on investment (ROI). E ity/property value in . qu creasesPreliminary Powerysis DataProperty resel value. Anal I It is important to determine the electricalenergy consumptionfor theSystem payback. periodbuilding. T following informationis needed on existing buildings. NewREC (green tag) income. he b dings must calculate this information.P -based incentives (PBls). uil erformance Utility b (highest bill per quarteru the past two years.Most software packages will generate charts and gr so that R and illsminim m) foraphsOIUsage pattern with peak, part-peak, and off-p u and summer andpayback cycles are cleareasy to un .software packages eaksageandderstand Some winter demand charges.can fill out therms needed for state and u lity r and the forms for fo ti ebatesC rent and future electric rate sch factoring in tiered rates and time commissioning the PV arr system with the utility company. ur edule,ay ateecessary pa erworktax of-use utility pricing and annual r inflation.Completing the n p for the rebates andcredits and Inventory list of major appliances and other-ampere dr equip being aware of the deadlines related to th rebates arery important. A high awingesevement (seasonal/nonseasonal).con r orcan in land liabilities if he or tracto designercur substantia costshe L and inventoryisting electrical services (photos).fails to complete the rebateper utility in nocateex andformance-basedce tives paperwork and forms in alytotific incentive tier dead . time fashionmee spec linesInformation ProcessingPreliminary Design 4Understan ng the reba and performance-basedincentive process is anddi te boveusedgettin theat make the The items a areto calculate the information needed to design thecritical forgclient and contractor the cost savings thPVsolarecon lyble. system.systemomical feasi Electrical L Determine building power r (total peak kW).T rebates and incentives vary; some states may requiresystoad:equirementshesePVemArray Sizing:array size requirements (kW).installation first,the owner then applying forcredit later on. In CalculatewiththesomeArray L module size, based on roof size and equipment locationscases, the state will only p if it has allocated fun inaccount at ayout:aydsthethe and pricing.time ofOther states require onereserve the rebates by first filing; a filing.toWiring System D~ voltage drop,building code, N code,set amount of time is then allocated to get the system installed and comsign:safetyECand environ missioned. Perform b incentives mean just that - over time, the ment.ance- ased Combiner:lo array system is monitored and is expected to perform as designed. So be Box size andcations.Controller Specifications: size of battery back-up system only.5careful with p production estim designing aarr sysowerates whensolarayInverter Specifications:z tem; alation could prove to be veryive! si e.miscalcu expensUtility-interactive system design. Note:npower g d,solar array shuts down unless Whe theri goes down the ita hasbattery system."