Annual Yield Check of Large Scale Solar Thermal Systems

This document describes a simple methodology for verifying the predicted annual yield of large-scale solar systems. This method was developed by Fraunhofer ISE and Solar Experience GmbH as part of the ProSolNetz project (FKZ: 03EN603F) (Bundesministerium für Wirtschaft und Klimaschutz [BMWK.IIB5] & Forschungszentrum Jülich GmbH [PT-J.ESN6], 2025) and is described in ISO/DIS 24194. This report is divided into an overview of currently available methods for field characterization, which are relevant in the context of method development. It shows the global objectives that were at the forefront of the development of a method for checking the annual yield of a large-scale solar installation, presents the most important changes in the revision of ISO 24194 in this context and describes the practical application of the annual yield check as well as the restrictions that the procedure imposes on the operating and environmental conditions.