This European Standard is part of a series of standards on the method for calculation of system energy requirements and system efficiencies. The framework for the calculation is described in prEN 15603. The scope of this specific part is to standardise the: ? required inputs, ? calculation method, ? required outputs, for thermal solar systems (including control) for space heating, domestic hot water production and the combination of both. The following typical thermal solar systems are considered: ? domestic hot water systems characterized by EN 12976 (factory made) or ENV 12977 (custom built); ? combisystems (for domestic hot water and space heating) characterized by ENV 12977 or the Direct Characterisation method developed in Task 26 ‘Solar Combisystems’ of the IEA Solar Heating and Cooling programme; ? space heating systems characterized by ENV 12977.