ASTM_E_2527_-_15.pdf

Designation:E252715Standard Test Method forElectrical Performance of Concentrator TerrestrialPhotovoltaic Modules and Systems Under Natural Sunlight1This standard is issued under the fixed designation E2527;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the elec-trical performance of photovoltaic concentrator modules andsystems under natural sunlight using a normal incidencepyrheliometer.1.2 The test method is limited to module assemblies andsystems where the geometric concentration ratio specified bythe manufacturer is greater than 5.1.3 This test method applies to concentrators that usepassive cooling where the cell temperature is related to the airtemperature.1.4 Measurements under a variety of conditions are al-lowed;results are reported under a select set of concentratorreporting conditions to facilitate comparison of results.1.5 This test method applies only to concentrator terrestrialmodules and systems.1.6 This test method assumes that the module or systemelectrical performance characteristics do not change during theperiod of test.1.7 The performance rating determined by this test methodapplies only at the period of the test,and implies no past orfuture performance level.1.8 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D6176 Practice for Measuring Surface Atmospheric Tem-perature with Electrical Resistance Temperature SensorsE772 Terminology of Solar Energy ConversionE816 Test Method for Calibration of Pyrheliometers byComparison to Reference PyrheliometersE1036 Test Methods for Electrical Performance of Noncon-centrator Terrestrial Photovoltaic Modules and ArraysUsing Reference Cells2.2 IEEE Standard:IEEE 929-2000 Recommended Practice for Utility Interfaceof Photovoltaic(PV)Power Systems3.Terminology3.1 DefinitionsDefinitions of terms used in this testmethod may be found in Terminology E772,and IEEEStandard 929.3.2 Definitions of Terms Specific to This Standard:3.2.1 Concentrator Reporting Conditions,n the ambienttemperature,wind speed,and direct normal solar irradiance towhich concentrator module or system performance data arecorrected.3.2.2 system,na photovoltaic module or array connectedto an inverter.3.3 Symbols:The following symbols and units are used inthis test method:E=direct normal irradiance,Wm-2Eo=reporting direct normal irradiance of 850 Wm-2P=maximum power,WPo=maximum power at concentrator reporting conditions(Eo,To,and Vo),WTa=ambient temperature,CTo=reporting ambient temperature of 20Cv=wind speed,ms-1vo=reporting wind speed of 4 ms-14.Summary of Test Method4.1 Determining the performance of a photovoltaic moduleor system under natural sunlight consists of measuring themaximum power over a range of irradiance and air tempera-ture.1This test method is under the jurisdiction of ASTM Committee E44 on Solar,Geothermal and OtherAlternative Energy Sources and is the direct responsibility ofSubcommittee E44.09 on Photovoltaic Electric Power Conversion.Current edition approved Feb.1,2015.Published March 2015.Originallyapproved in 2006.Last previous edition approved in 2009 as E2527-09.DOI:10.1520/E2527-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2 Amultiple linear regression is used to rate the maximumpower3at standard concentrator reporting conditions,definedas To=20C,vo=4 ms-1,Eo=850 Wm-2.4.2.1 A direct normal irradiance of 850 Wm-2was selectedfrom a resource assessment study4that showed when the globalnormal solar irradiance is near the 1000 Wm-2used in ratingflat-plate photovoltaic modules,the direct normal irradiance isabout 850 Wm-2.4.3 The actual test data and the performance results are thenreported.5.Significance and Use5.1 It is the intent of this test method to provide a recog-nized procedure for testing and reporting the electrical perfor-mance of a photovoltaic concentrator module or system.5.2 If an inverter is used as part of the system,this testmethod can provide a dc or ac rating or both.The dc or acrating depends on whether the inverter input or output ismonitored.5.3 The test results may be used for comparison among agroup of modules or systems from a single source.They alsomay be used to compare diverse de