GSRad

GSRad is a cross-platform component containing routines to calculate daily and hourly values of extra-terrestrial and ground-level global solar radiation. The latter is both generated using stochastic approaches or estimated by means of physical relationships between solar radiation and other weather variables (i.e. air temperature, sunshine duration, cloud cover). Clear sky transmissivity is estimated according to alternative approaches. Provisions are supplied to have ground-level global solar radiation partitioned into direct, diffuse, and reflected components. Methods to estimate daily and hourly photosynthetically active radiation, both as lumped and partitioned by beam and diffuse components, are also provided. Finally, methods are also implemented to extract slope and aspect angles from elevation data. A summary diagram of the set of methods implemented is linked here.

The component implements the test of pre-conditions and post-conditions for each of the models provided, allowing an input on screen, TXT or XML file; custom output drivers can also be developed. Moreover, data sets used to perform unit tests on each of the models made available are also provided as part of this documentation.

The component can be freely used and distributed by modellers and developers in their own applications, if the application contains either a dedicated menu item or a dedicated button calling the info() method of the component. This method displays information about the component and a button which activates the help of the component (examples of how to do this are shown in the sample applications provided to illustrate the use of the component). The component can be used in code developed using any Windows or Linux programming language (VB.NET, C#, C++: C# version; Java: Java version; the COM version made available as prototype prior to this release is neither supported nor updated with respect to this version). The component design allows for expansions by the users that can add easily their own models. Three sample clients are provided inclusive of source code to demonstrate how to add models (C# version), to build a Win .NET application (C# version), and to built a Java application (Java version). A sample web service and a sample web application are available on line as further examples of possible use of the component.