Defining the Reference Hotel – toward nearly Zero Energy Hotels design

The ever mentioned “cost optimality” and “nearly Zero Energy Buildings” concepts, introduced by the EPBD recast, are still a blurry target at EU Member States’ level for non-residential buildings. Among the uncertainties hampering a quantitative description of cost optimal and nearly Zero Energy (nZE) level of energy performance in these building categories, the definition of the “typical energy use of a building” [1], is a key issue. Indeed, in non-residential buildings the energy use for maintaining occupants’ comfort (identified as the “typical”) is complementary to the energy use for maintaining the offered services’ quality. Given the general issue, the paper focuses on hotels. As an initial step toward nZE hotels, this study presents the definition of an existing Reference Hotel. First, typical and extra functions of a small-medium hotel were defined. Then, the general procedure for defining a Reference Hotel (RH) was drafted and an Italian RH was modelled: internal layout, envelope, systems features and operation profiles were identified. A dynamic energy simulation of the model was run to evaluate its energy performances. Results were then compared to benchmarks from literature. Next steps will exploit the Reference Hotel to investigate potential relations with the energy uses for extra services and to propose cost-optimal and energy efficient retrofit measures.