Sun Position

Sun Position will be a valuable resourcefor programmers and solar engineers of this century.

Knowing where the sun is at in the sky, with high accuracy, is at the core of all solar energy research, whether for site planning, or real time aiming of the most sophisticated concentrating receivers, heliostats, and photovoltaic tracking systems. Sun Position meets this need with two well-documented, easy-to-implement and easy-to-translate Visual Basic algorithms. For most applications the concise 0.02 degree accuracy code works very well. However, for the most exacting requirements, Sun Position also presents a precision algorithm accurate to within 0.00003 degrees.

John Clark Craig, author of many computer programming books for Microsoft, has also programmed solar algorithms for several of the largest solar energy projects, located all over the world. While developing control and monitoring software systems for these projects, John constantly searched for the best algorithms and improved code for determining accurate sun position. Most of the available documentation was not easy to use, with bits and pieces of algorithms here and there, mixed in with poorly explained terminology, and with very little guidance for translating to other programming languages. John vowed to write Sun Position as the reference book he wished he had all along, with easy to read and easy to translate code, check points, validation test cases and debugging help.