
In the applications of solar energy, the solar radiation components data in a site must be known for the design of a system. However, for many developing countries solar radiation data are only available for site stations due to the cost of the measurement equipment and techniques involved. The present work proposes a simple model to estimate the direct, diffuse, and total solar radiation on horizontal surfaces. Calculations of this model were made for solar solstices and equinox for the purpose of testing. Results showed that the model provides an acceptable estimation of the direct, diffuse, and total components of solar radiation components. This simple model can be used at any location in the northern hemisphere.