Design principles and field performance of a solar spectral irradiance meter

• Published in: Solar energy 2016-08, Vol.133, p.94-102
• Main Authors: Tatsiankou, V., Hinzer, K., Haysom, J., Schriemer, H., Emery, K., Beal, R.
• Format: Article
• Language: English
• Subjects: absolute cavity radiometer; Atmospheric parameterization; Comparative analysis; Direct normal spectral irradiance; Measurement; OTHER INSTRUMENTATION; pyrheliometer; Radiometers; Solar energy; Solar resource assessment; Solar spectral irradiance meter; Solar spectrum; spectroradiometer; SSIM
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2016.03.054

•A solar spectral irradiance meter (SSIM) uses ground-based measurements to inform software algorithm for rapid resolution of the solar spectrum across the entire 280–4000nm range.•Two SSIMs were tested and calibrated at the National Renewable Energy Laboratory (NREL) against four spectroradiometers and an absolute cavity radiometer.•The cumulative energy density collected by the SSIM over an eight month period agreed with that measured by an Eppley model NIP pyrheliometer to within 0.5%.•No degradation of bandpass filter performances or detector sensitivities was observed.•The difference in integrated daily spectral irradiance between the SSIM and the ASD spectroradiometer was found to be less than 1%. A solar spectral irradiance meter (SSIM), designed for measuring the direct normal irradiance (DNI) in six wavelength bands, has been combined with models to determine key atmospheric transmittances and the resulting spectral irradiance distribution of DNI under all sky conditions. The design principles of the SSIM, implementation of a parameterized transmittance model, and field performance comparisons of modeled solar spectra with reference radiometer measurements are presented. Two SSIMs were tested and calibrated at the National Renewable Energy Laboratory (NREL) against four spectroradiometers and an absolute cavity radiometer. The SSIMs’ DNI was on average within 1% of the DNI values reported by one of NREL’s primary absolute cavity radiometers. An additional SSIM was installed at the SUNLAB Outdoor Test Facility in September 2014, with ongoing collection of environmental and spectral data. The SSIM’s performance in Ottawa was compared against a commercial pyrheliometer and a spectroradiometer over an eight month study. The difference in integrated daily spectral irradiance between the SSIM and the ASD spectroradiometer was found to be less than 1%. The cumulative energy density collected by the SSIM over this duration agreed with that measured by an Eppley model NIP pyrheliometer to within 0.5%. No degradation was observed.