EuroSun2008-5

Classification of thermal solar systems

As can be seen from the title of the standards, the thermal solar systems have been divided into two groups: “factory made systems” and “custom built systems”. This division was necessary in order to be able to include the whole spectrum of thermal solar systems in Europe, which ranges from small compact systems (thermo-siphon and integrated collector-storage-systems) to very large systems individually designed by engineers. The classification of a system “as factory” made or “custom built” is a choice of the final supplier in accordance to the following definitions:

Factory made solar heating systems are batch products with one trade name, sold as complete and ready to install kits, with fixed configuration. Systems of this class are considered as a single product and assessed as a whole. For the determination of its thermal performance, such a system is tested as one complete unit. If a factory made solar heating system is modified by changing its configuration

or by changing one or more of its components, the modified system is considered as a new system for which a new test report is necessary.

Custom built solar heating systems are either uniquely built, or assembled by choosing from an assortment of components. Systems of this category are regarded as a set of components. The components are separately tested and test results are integrated to an assessment of the whole system.

Custom built solar heating systems are subdivided into two categories:

Large custom built systems are uniquely designed for a specific situation. In general HVAC engineers, manufacturers or other experts design them (HVAC: heating, ventilation, air­conditioning).

Small custom built systems offered by a company are described in a so called assortment file, in which all components and possible system configurations, marketed by the company, are specified. Each possible combination of a system configuration with components from the assortment is considered as one custom built system.

Table 2 summarises the different types of thermal solar systems. As a consequence of this way of classification, forced circulation systems can be considered either as factory made or as custom built, depending on the market approach chosen by the final supplier. Hence it is essential that the performance of these systems is determined for the same set of reference conditions as specified in Annex B of EN 12976-2 and Annex A of ENV 12977-2.

During the past four years the standards listed above were revised and updated. This procedure resulted in the publication of the following revised version or new parts of standards respectively (see Table 3). The most important changes and highlights resulting from the revision will be described separately for each of the three standard series in the following chapters.