This European Standard specifies a calculation method for the energy performance of storage systems used for ventilation systems. It takes into account the energy performance of storage systems using water from phase change material (PCM) to store cooling energy. This standard presents a general method applicable to the different technologies of water-based storage systems or PCM related controls systems. It does not cover the cooling emission, distribution and generation that are covered by EN 15316 2, EN 15316 3 and EN 16798-13 respectively.The standard covers typically hourly time steps but can be adapted to different time steps accordingly with the scenarios used for energy use and energy delivered or to bin method.A simplified method is provided for monthly or annual time step.This standard does not cover:-the cooling emission, distribution and generation systems; or-sizing or inspection of such storage systems.Table 1 shows the relative position of this standard within the set of EPB standards in the context of the modular structure as set out in prEN ISO 52000 1:2015.NOTE 1In prCEN ISO/TR 52000 2 the same table can be found, with, for each module, the numbers of the relevant EPB standards and accompanying technical reports that are published or in preparation.NOTE 2The modules represent EPB standards, although one EPB standard might cover more than one module and one module might be covered by more than one EPB standard, for instance a simplified and a detailed method respectively. See also Clause 2 and Tables A.1 and B.1.Table 1 - Position of this standard (in casu M4-7) within the EPB set of standards...