Solar and Infrared Radiation Measurements

Appendix A :Modeling Solar Radiation

A.1 Introduction

Before incident solar radiation is measured, it’s important to understand the characteristics and magnitude of the incoming irradiance and how the radiation is changed as it passes through the atmosphere. Solar radiation basics are discussed in Chapter 2, and spectral characteristics are covered in Chapter 12. From the existing data and with knowledge of the characteristics of solar irradiance, a wide variety of models have been created to estimate irradiance from meteorological parameters, atmospheric constituents, and a limited set of irradiance measurements. Some models exist to estimate solar radiation on clear days, and other models have been created to estimate direct horizontal irradiance ...