Hukseflux SR05 series - 4.4 Specific Use for Outdoor PV System Performance Testing

SR05-D1A3-PV manual v1801 24/83
WMO has approved the “pyranometric method” to estimate sunshine duration from
pyranometer measurements (Chapter 8 of the WMO Guide to Instruments and
Observation, 2008). This implies that a pyranometer may be used, in combination with
appropriate software, to estimate sunshine duration. Ask for our application note.
Table 4.3.1 Standards with recommendations for instrument use in sunshine duration
measurement
STANDARDS FOR INSTRUMENT USE FOR SUNSHINE DURATION
WMO
WMO-No. 8; Guide to Meteorological Instruments and Methods of Observation, chapter 8,
measurement of sunshine duration, 8.2.2 Pyranometric Method
4.4 Specific use for outdoor PV system performance testing
Pyranometers are used for monitoring PV power plant efficiency, in order to measure
incoming solar radiation independently from the PV system. Pyranometers can be placed
in two positions:
• plane of array (POA), parallel to the PV panels, for measurement of the in-plane
irradiance (also noted as G
i in IEC 61724-1)
• horizontally, for measurement of the global horizontal irradiance (E, also noted as GHI
in IEC 61724-1)
SR05 series is applicable in outdoor PV system performance testing. See also Hukseflux
model SR15-D1 “digital first class pyranometer” and SR30-D1 “digital secondary
standard pyranometer”.
Table 4.4.1 Standards with recommendations for instrument use in PV system
performance testing
STANDARDS ON PV SYSTEM PERFORMANCE TESTING
IEC / ISO STANDARD
EQUIVALENT ASTM STANDARD
IEC 61724-1; Photovoltaic system performance
monitoring – guidelines for measurement, data
exchange and analysis
COMMENT: Allows pyranometers or reference
cells according to IEC 60904-2 and -6.
Pyranometer reading required accuracy better
than 5% of reading (Par 4.1)
COMMENT: equals JISC 8906 (Japanese
Industrial Standards Committee)
ASTM 2848-11; Standard Test Method for
Reporting Photovoltaic Non-Concentrator
System Performance
COMMENT: confirms that a pyranometer is the
preferred instrument for outdoor PV testing.
Specifically recommends a “first class”
pyranometer (paragraph A 1.2.1.)