Regarding TRNSYS models, novel types were created for absorption chillers, using COP values from manufacturers’ data (not just COP max but COP(T)). The model is able to run for a whole year (365 days) according to control rules, self-deciding whether to operate in heating or cooling mode.

For building simulation, Type12c was used in the model. Type12c was used instead Type56 because it is less complex and the results have enough accuracy for the purpose of studying the system. The models also consider solar gains through the glazed area. Typelb allows the simulation of a flat-plate collector. In order to simplify the model, the same type was used for simulating the vacuum tube collector. For thermal storage, several stratified tanks with variable inlet and uniform heat losses were considered — Type4c. Several data files of absorption chillers were created according to Yazaki and Phonix chiller technical data, with Type107. For the electrical vapor compression chiller Type53 was used with a data file containing information of the

YorkLCHHM200 WL machine. Other types used were: Type109-TMY2, Type3b for simulation of pumps and cooling tower (less complex compared to Type51), Type91 and Type6.

For the hotel and office building located in Rome and Lisbon, cooling needs correspond to 65 up to 85% of the total thermal load. In Berlin, those buildings have more heating needs, although cooling needs to be considered because it represents 15 to 25% of the total thermal load.

In a single-family house, the cooling load is not so high because it doesn’t match so considerably with occupation time (except on weekends). In Rome and Lisbon it corresponds to values between 25-40%. For Berlin, it can be neglected (less than 5%).

4 Results