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ASTM E973-05a

(Test Method)

Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell

Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell

SIGNIFICANCE AND USE
The calculated error in the photovoltaic device current determined from the spectral mismatch parameter can be used to determine if a measurement will be within specified limits before the actual measurement is performed.
The spectral mismatch parameter also provides a means of correcting the error in the measured device current due to spectral mismatch.
5.2.1 The spectral mismatch parameter is formulated as the fractional error in the short-circuit current due to spectral differences.3 ,4  
5.2.2 Error due to spectral mismatch can be corrected by dividing the measured photovoltaic cell current by M, a procedure used in Test Methods E 948 and E 1036
SCOPE
1.1 This test method covers a procedure for the determination of a spectral mismatch parameter used in performance testing of photovoltaic devices.
1.2 The spectral mismatch parameter is a measure of the error, introduced in the testing of a photovoltaic device, caused by mismatch between the spectral responses of the photovoltaic device and the photovoltaic reference cell, as well as mismatch between the test light source and the reference spectral irradiance distribution to which the photovoltaic reference cell was calibrated. Examples of reference spectral irradiance distributions are Tables E 490 or G 159.
1.3 The spectral mismatch parameter can be used to correct photovoltaic performance data for spectral mismatch error.
1.4 This test method is intended for use with linear photovoltaic devices.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
31-Aug-2005
ICS
27.160 - Solar energy engineering
Technical Committee
E44 - Solar, Geothermal and Other Alternative Energy Sources
Drafting Committee
E44.09 - Photovoltaic Electric Power Conversion
Current Stage
Ref Project

Relations

Replaces
ASTM E973-05 - Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell
Effective Date
01-Sep-2005
Replaced By
ASTM E973-10 - Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell
Effective Date
01-Jun-2010
Referred By
ASTM G214-23 - Standard Test Method for Integration of Digital Spectral Data for Weathering and Durability Applications
Effective Date
01-Sep-2005
Referred By
ASTM E1362-15(2019) - Standard Test Methods for Calibration of Non-Concentrator Photovoltaic Non-Primary Reference Cells
Effective Date
01-Sep-2005
Referred By
ASTM G113-22 - Standard Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic Materials
Effective Date
01-Sep-2005
Referred By
ASTM G130-12(2020) - Standard Test Method for Calibration of Narrow- and Broad-Band Ultraviolet Radiometers Using a Spectroradiometer
Effective Date
01-Sep-2005
Referred By
ASTM E1036-15(2019) - Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells
Effective Date
01-Sep-2005
Referred By
ASTM E927-19 - Standard Classification for Solar Simulators for Electrical Performance Testing of Photovoltaic Devices
Effective Date
01-Sep-2005
Referred By
ASTM E948-16(2020) - Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight
Effective Date
01-Sep-2005
Referred By
ASTM E2848-13(2023) - Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
Effective Date
01-Sep-2005
Referred By
ASTM E2236-10(2019) - Standard Test Methods for Measurement of Electrical Performance and Spectral Response of Nonconcentrator Multijunction Photovoltaic Cells and Modules
Effective Date
01-Sep-2005
Referred By
ASTM E1021-15(2019) - Standard Test Method for Spectral Responsivity Measurements of Photovoltaic Devices
Effective Date
01-Sep-2005
Referred By
ASTM E1125-16(2020) - Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum
Effective Date
01-Sep-2005

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ASTM E973-05a - Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference CellASTM E973-05a - Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell
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ASTM E973-05a - Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:E973–05a
Standard Test Method for
Determination of the Spectral Mismatch Parameter Between
1
a Photovoltaic Device and a Photovoltaic Reference Cell
This standard is issued under the fixed designation E973; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Using Reference Cells
E1039 Test Method for Calibration of Silicon Non-
1.1 This test method covers a procedure for the determina-
Concentrator Photovoltaic Primary Reference Cells Under
tion of a spectral mismatch parameter used in performance
3
Global Irradiation
testing of photovoltaic devices.
E1125 Test Method for Calibration of Primary Non-
1.2 The spectral mismatch parameter is a measure of the
Concentrator Terrestrial Photovoltaic Reference Cells Us-
error,introducedinthetestingofaphotovoltaicdevice,caused
ing a Tabular Spectrum
by mismatch between the spectral responses of the photovol-
E1328 Terminology Relating to Photovoltaic Solar Energy
taic device and the photovoltaic reference cell, as well as
Conversion
mismatch between the test light source and the reference
E1362 Test Method for Calibration of Non-Concentrator
spectral irradiance distribution to which the photovoltaic ref-
Photovoltaic Secondary Reference Cells
erence cell was calibrated. Examples of reference spectral
G138 Test Method for Calibration of a Spectroradiometer
irradiance distributions are Tables E490 or G173.
Using a Standard Source of Irradiance
1.3 The spectral mismatch parameter can be used to correct
G173 Tables for Reference Solar Spectral Irradiances: Di-
photovoltaic performance data for spectral mismatch error.
rect Normal and Hemispherical on 37° Tilted Surface
1.4 This test method is intended for use with linear photo-
SI10 Standard for Use of the International System of Units
voltaic devices.
(SI): The Modern Metric System
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Terminology
responsibility of the user of this standard to establish appro-
3.1 Definitions—Definitions of terms used in this test
priate safety and health practices and determine the applica-
method may be found in Terminology E772 and Terminology
bility of regulatory limitations prior to use.
E1328.
2. Referenced Documents 3.2 Definitions of Terms Specific to This Standard:
2 3.2.1 test light source, n—a source of illumination whose
2.1 ASTM Standards:
spectral irradiance will be used for the spectral mismatch
E490 Standard Solar Constant and Zero Air Mass Solar
calculation.
Spectral Irradiance Tables
3.3 Symbols—The following symbols and units are used in
E772 Terminology Relating to Solar Energy Conversion
this test method:
E948 Test Method for Electrical Performance of Photovol-
M—spectral mismatch parameter,
taicCellsUsingReferenceCellsUnderSimulatedSunlight
´—measurement error in short-circuit current,
E1021 Test Method for Spectral Responsivity Measure-
l—wavelength, µm or nm,
ments of Photovoltaic Devices
−1
R (l)—spectral response of reference cell, AW ,
r
E1036 TestMethodsforElectricalPerformanceofNoncon-
−1
R(l)—spectral response of photovoltaic device, AW ,
t
centrator Terrestrial Photovoltaic Modules and Arrays
−2
E—irradiance, Wm ,
−2 −1 −2 −1
E (l)—spectral irradiance, Wm µm or Wm nm ,
and
1
This test method is under the jurisdiction of ASTM Committee E44 on Solar, −2 −1
E (l)—reference spectral irradiance, Wm µm or
o
Geothermal,andOtherAlternativeEnergySourcesandisthedirectresponsibilityof
−2 −1
Wm nm .
Subcommittee E44.09 on Photovoltaic Electric Power Conversion.
CurrenteditionapprovedSeptember1,2005.PublishedOctober2005.Originally
NOTE 1—Following normal SI rules for compound units (see Practice
approved in 1983. Last previous edition approved in 2005 as E973–05. DOI:
SI10), the units for spectral irradiance, the derivative of irradiance with
10.1520/E0973-05A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Withdrawn. The last approved version of this historical standard is referenced
the ASTM website. on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
E973–05a
−3
respect to wavelength dE/d (l), would be Wm . However, to avoid
7. Procedure
possible confusion with a volumetric power density unit and for conve-
7.1 Determine the spectral response R(l) of the photovol-
...

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5.1 This practice can be used to determine an expected capacity for an existing or a proposed photovoltaic system in a particular location during a specified period of time (see data collection period in Test Method E2848).  
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Standard Practice for Determining Resistance of Solar Collector Covers to Hail by Impact with Propelled Ice Balls

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2.1 In many geographic areas there is concern about the effect of falling hail upon solar collector covers. This practice may be used to determine the ability of flat-plate solar collector covers to withstand the impact forces of hailstones. In this practice, the ability of a solar collector cover plate to withstand hail impact is related to its tested ability to withstand impact from ice balls. The effects of the impact on the material are highly variable and dependent upon the material.  
2.2 This practice describes a standard procedure for mounting the test specimen, conducting the impact test, and reporting the effects.  
2.2.1 The procedures for mounting cover plate materials and collectors are provided to ensure that they are tested in a configuration that relates to their use in a solar collector.  
2.2.2 The corner locations of the four impacts are chosen to represent vulnerable sites on the cover plate. Impacts near corner supports are more critical than impacts elsewhere. Only a single impact is specified at each of the impact locations. For test control purposes, multiple impacts in a single location are not permitted because a subcritical impact may still cause damage that would alter the response to subsequent impacts.  
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SCOPE
1.1 This practice covers a procedure for determining the ability of cover plates for flat-plate solar collectors to withstand impact forces of falling hail. Propelled ice balls are used to simulate falling hailstones. This practice is not intended to apply to photovoltaic cells or arrays.  
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SIGNIFICANCE AND USE
4.1 Although this practice is intended for evaluating solar absorber materials and coatings used in flat-plate collectors, no single procedure can duplicate the wide range of temperatures and environmental conditions to which these materials may be exposed during in-service conditions.  
4.2 This practice is intended as a screening test for absorber materials and coatings. All conditions are chosen to be representative of those encountered in solar collectors with single cover plates and with no added means of limiting the temperature during stagnation conditions.  
4.3 This practice uses exposure in a simulated collector with a single cover plate. Although collectors with additional cover plates will produce higher temperatures at stagnation, this procedure is considered to provide adequate thermal testing for most applications.
Note 1: Mathematical modeling has shown that a selective absorber, single glazed flat-plate solar collector can attain absorber plate stagnation temperatures as high as 226 °C (437 °F) with an ambient temperature of 37.8 °C (100 °F) and zero wind velocity, and a double glazed one as high as 245 °C (482 °F) under these conditions. The same configuration solar collector with a nonselective absorber can attain absorber stagnation temperatures as high as 146 °C (284 °F) if single glazed, and 185 °C (360 °F) if double glazed, with the same environmental conditions (see “Performance Criteria for Solar Heating and Cooling Systems in Commercial Buildings,” NBS Technical Note 1187).4  
4.4 This practice evaluates the thermal stability of absorber materials. It does not evaluate the moisture stability of absorber materials used in actual solar collectors exposed outdoors. Moisture intrusion into solar collectors is a frequent occurrence in addition to condensation caused by diurnal breathing.  
4.5 This practice differentiates between the testing of spectrally selective absorbers and nonselective absorbers.  
4.5.1 Testing Spectrally Selective...
SCOPE
1.1 This practice covers a test procedure for evaluating absorptive solar receiver materials and coatings when exposed to sunlight under cover plate(s) for long durations. This practice is intended to evaluate the exposure resistance of absorber materials and coatings used in flat-plate collectors where maximum non-operational stagnation temperatures will be approximately 200 °C (392 °F).  
1.2 This practice shall not apply to receiver materials used in solar collectors without covers (unglazed) or in evacuated collectors, that is, those that use a vacuum to suppress convective and conductive thermal losses.  
1.3 The values stated in SI units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E782-95(2022)(Practice)
Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

SIGNIFICANCE AND USE
3.1 This practice describes a weathering box test fixture and provides uniform exposure guidelines to minimize the variables encountered during outdoor exposure testing.  
3.2 This practice may be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
3.3 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either alone, a weathering box that elevates the temperature of the cover materials is used.  
3.4 This practice is intended to assist in the evaluation of solar collector cover materials in the operational, not stagnation mode. Insufficient data exist to obtain exact correlation between the behavior of materials exposed according to this practice and actual in-service performance.  
3.5 Means of evaluation of effects of weathering are provided in Practice E781, and in other ASTM test methods that evaluate material properties.  
3.6 Tests of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences which comprise weather. Exposure conditions are complex and changeable. Important factors are solar radiation, temperature, moisture, time of year, presence of pollutants, etc. These factors vary from site to site and should be considered in selecting locations for exposure. Control samples must always be used in weathering tests for comparative analysis. Outdoor exposure for at least two years is required to make evident changes, such as surface degradation without the use of sophisticated analytical equipment.  
3.7 Temperature conditions attained with this box may not exactly duplicate those that occur under operational conditions with fluid flow. Dependent on environmental exposure conditions, the cover plate temperatures obtained with this box may be higher or lower than those obtained und...
SCOPE
1.1 This practice provides a procedure for the exposure of cover materials for flat-plate solar collectors to the natural weather environment at temperatures that are elevated to approximate operating conditions.  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors or photovoltaics.  
1.4 The values stated in SI units are to be regarded as the standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E881-92(2022)(Practice)
Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

SIGNIFICANCE AND USE
4.1 This practice describes a weathering box test fixture and establishes limits for the heat loss coefficients. Uniform exposure guidelines are provided to minimize the variables encountered during outdoor exposure testing.  
4.2 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either exposure alone, a weathering box that elevates the temperature of the cover materials is used.  
4.3 This practice may be used to assist in the evaluation of solar collector cover materials in the stagnation mode. No single temperature or procedure can duplicate the range of temperatures and environmental conditions to which cover materials may be exposed during stagnation conditions. To assist in evaluation of solar collector cover materials in the operational mode, Practice E782 should be used. Insufficient data exist to obtain exact correlation between the behavior of materials exposed in accordance with this practice and actual in-service performance.  
4.4 This practice may also be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
4.5 Means of evaluating the effects of weathering are provided in Practice E765, and in other ASTM test methods that evaluate material properties.  
4.6 Exposures of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences that comprise weather. Exposure conditions are complex and changeable. Important factors are material temperature, climate, time of year, presence of industrial pollution, etc. Generally, because it is difficult to define or measure precisely the factors influencing degradation due to weathering, results of outdoor exposure tests must be taken as indicative only. Repeated exposure testing at different seasons over a period of more than one year is req...
SCOPE
1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2·°C).  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2·°C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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