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ARM Pyrgeometer Calibrations Update

Broadband Radiometric Measurements Group

Tom StoffelIbrahim RedaMark Kutchenreiter

29 March 2011

NATIONAL RENEWABLE ENERGY LABORATORY

Solar Radiation Research Lab (SRRL)

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Construction ProjectScheduled Completion:

June 2011

NATIONAL RENEWABLE ENERGY LABORATORY

Radiometer Infrastructure Upgrades

SIRS• New Mounting Fixtures• Upgraded Data Loggers• Replace Signal Cables/Connectors

Radiometer Calibration Facility• Replace Signal Cables/Connectors• Implement Pyrgeometer Calibrations Traceable to

World Infrared Standard Group (ECO-00781)

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NATIONAL RENEWABLE ENERGY LABORATORY

SIRS Upgrades

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Since ~1993 New A-Frame

NATIONAL RENEWABLE ENERGY LABORATORY

SIRS Upgrades

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• Signal Cables• Power Cables• Conduits• Campbell Loggers CR-3000

NEW

NATIONAL RENEWABLE ENERGY LABORATORY

RCF Upgrades

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• BORCAL (Shortwave)• BORCAL (Longwave = PYRG-CAL)

New Hardware & PROCESS

NEW

Pyrgeometer Calibration ProcessWISGWorld Reference

NREL Reference

NREL Transfer Standards (+/- 2 W/m2 agreement with NOAA/GMD)

ARM/SGP Transfer Standards

ARM Field Pyrgeometers

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Pyrgeometer Calibration Action Items

(6) Frequency: Two Year Cycle using outdoor method

(7a) EPLAB Re-cal for 10 PIRs for comparisonwith original results:Six (6) SIRS PIRs going to EPLAB as wespeak

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Compare WISG with NREL Calibrations

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NATIONAL RENEWABLE ENERGY LABORATORY

Compare WISG with NREL Calibrations

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NATIONAL RENEWABLE ENERGY LABORATORY

Compare WISG with EPLAB Calibrations

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NATIONAL RENEWABLE ENERGY LABORATORY

Joe’s Validation of NREL Equation

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NATIONAL RENEWABLE ENERGY LABORATORY 13

NATIONAL RENEWABLE ENERGY LABORATORY 14

NATIONAL RENEWABLE ENERGY LABORATORY

Pyrgeometer Calibration Action Items

(7b) Compare PIRs with new (WISG) ARM calibrations with original EPLAB calibrations using 2-coefficient formula:

_Original Cal and case-dome coeff = 4.0_Original Cal and new case-dome coeff_New Cal and new case-dome coeff_New Cal and 3-Coeff formula_Compare above to see differences…

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ARM Pyrgeometer Calibrations UpdateSolar Radiation Research Lab (SRRL)Radiometer Infrastructure UpgradesSIRS UpgradesSIRS UpgradesRCF UpgradesPyrgeometer Calibration ProcessPyrgeometer Calibration Action ItemsCompare WISG with NREL CalibrationsCompare WISG with NREL CalibrationsCompare WISG with EPLAB CalibrationsJoe’s Validation of NREL EquationSlide Number 13Slide Number 14Pyrgeometer Calibration Action Items