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AssessingSolar is a practical guide to solar resource assessment in Python, aiming to make it easy to obtain solar radiation data, apply radiation models, and make accurate forecasts. The development of this guide is a collaborative effort within the IEA Photovoltaic Power Systems Programme (PVPS) Task 16.

Contrary to traditional textbooks or scientific articles, this guide presents the various topics of solar resource assessment with interactive plots and documented how-to examples using Python code. This is achieved using Jupyter Notebooks, which permits seamless integration of explanatory text, code examples, figures, mathematical equations, and references. The Python programming language was chosen as it is open-source, easy to learn, and the primary choice for the majority of open-source solar and PV libraries, including pvlib, which is extensively used throughout this guide.

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