The role of hybrid systems in the decarbonization of residential heritage buildings in Mediterranean climate. A case study in Seville, Spain

Abstract

Residential heritage buildings in the Mediterranean region face unexpected challenges in the field of energy efficiency and indoor environmental quality to ensure the sustainable conservation of historic town centres. This paper evaluates whether the conservation of their values can coexist with the current energy efficiency requirements and be included in urban decarbonization plans to prevent neglect and degradation. For this, a comprehensive decarbonization plan was drawn up based on the results of a previous energy audit on the case study selected, an 18th-century listed residential building in Seville, Spain. Envelope improvement was combined with mechanical ventilation and an integrated heat pump combining RESs and electricity from the public grid to cover all thermal needs in order to reach NZEB performance in the building. Despite the complexity of integrating demanding energy efficiency standards into heritage buildings, which requires case-by-case analysis and dynamic simulation, findings show a notable degree of approximation to NZEB performance. The main obstacles stem from the large amount of energy consumed by auxiliary systems and the relatively low presence of RESs in the national electricity mix.