Uncertainty in the Calibration Transfer of Solar Irradiance Scale: From Absolute Cavity Radiometers to Standard Pyrheliometers

In this work, the method for calculation of uncertainty of pyrheliometers’ responsivity during their outdoor calibration process in the laboratory is exposed. It is applied first for calibration of standard pyrheliometers by comparison to cavity radiometers, and after for calibration of an end-user...

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Detalles Bibliográficos
Autores: Balenzategui, José Lorenzo, Molero García, María, Silva, José Pedro, Fabero, Fernando, Cuenca, José, Mejuto, Eduardo, de Lucas Veguillas, Javier
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Instituto Nacional de Técnica Aeroespacial (INTA)
Repositorio:DIGITAL.INTA Repositorio Digital del Instituto Nacional de Técnica Aeroespacial
OAI Identifier:oai:digital.inta.es:20.500.12666/839
Acceso en línea:https://www.mdpi.com/2673-9941/2/2/10
http://hdl.handle.net/20.500.12666/839
https://doi.org/10.3390/solar2020010
Access Level:acceso abierto
Palabra clave:Solar irradiance
Calibration
Cavity radiometers
Pyrheliometers
Solar metrology
Uncertainty
Traceability
Descripción
Sumario:In this work, the method for calculation of uncertainty of pyrheliometers’ responsivity during their outdoor calibration process in the laboratory is exposed. It is applied first for calibration of standard pyrheliometers by comparison to cavity radiometers, and after for calibration of an end-user pyrheliometer against that standard pyrheliometer. The dissemination of the WRR irradiance scale is illustrated in practice and the increasing uncertainty in the traceability chain is quantified. The way of getting traceability to both WRR scale and to SI units in the current situation, where the shift between these radiometric scales is pending to be solved, is also explained. However, the impact of this gap between scales seems to be more important for calibrations of reference Class A pyrheliometers than in the final determination of DNI irradiance, because in this case, the cumulative uncertainty is large enough as to not significantly be affected for the difference. The way to take into account different correction terms in the measurement model function, and how to compute the corresponding uncertainty, is explained too. The influence of temperature of some pyrheliometers during calibration process and the potential impact on the DNI irradiance calculated with these instruments is exemplified.