Energy Efficiency in Historic Museums: The Interplay between Thermal Rehabilitation, Climate Control Strategies and Regional Climates Hugo Entradas Silva, Fernando M. A. Henriques Applied Sciences Switzerland, 2023 Museums housed in historical buildings combine the intrinsic value of the collections with the historical and architectural values of the building itself. Although usually made with thick elements with high thermal inertia, very effective in damping and delaying the heat flow, these buildings are usually characterized by elements with low thermal resistance, poor-quality windows and low area/volume ratio in the noblest buildings, which renders them ineffective at maintaining a stable indoor climate adequate for conservation, comfort and energy efficiency issues. In this paper, a simulation study was carried out to analyze the impact of the building location (weather), thermal envelope and climate control strategies by analyzing a generic room of the National Museum of Ancient Art of Lisbon. A simulation study was carried out for 15 European cities to verify the impossibility of standardizing the rehabilitation solutions in cultural heritage since energy needs depend on the location. It was concluded that the focus on climate control strategies has great potential for energy reduction and that in temperate climates of southern Europe, the improvement of thermal transmittance has a reduced effect on the building’s response.
Study of Natural Ventilation Strategies in the São Cristóvão Church in Lisbon Using a Multizone Airflow Model Luis G. Baltazar, João Alcobia, Hugo Entradas Silva Applied Sciences Switzerland, 2023 Visitors have a significant impact on the indoor climate of buildings housing works of art, and the relationship between the number of visitors, the indoor air quality and the protection of exposed works of art is an important factor in the overall study of the indoor climate of heritage buildings without mechanical ventilation and/or air-conditioning systems. In view of these concerns and the lack of studies on natural ventilation in heritage buildings, this study aims to analyse the performance of natural ventilation in the São Cristóvão Church in Lisbon, Portugal. For the preparation of this study, an analysis of the natural ventilation of this church was carried out by creating a model in the CONTAM software, and the indoor air quality was analysed based on different international standards and guidelines for carbon dioxide levels and air flow rates (ACH). Estimating the current ventilation strategy, an average ACH of 0.75 h−1 was estimated during the time the church is open, and an ACH of 0.15 h−1 was estimated during the time the doors were closed. In a yearly analysis, an average ACH of 0.30 h−1 was obtained. These air exchange values guarantee EN 16798-1 category I air quality for 72% of the year and category II air quality for 18% of the year. Different natural ventilation strategies were analysed: (a) three scenarios exploring different cross ventilation scenarios; (b) a scenario assuming that the church is closed all year round; and (c) a scenario estimating an increase in the number of visitors, giving an idea of the variations in human pollutants and possible consequences. Taking into account the air infiltration and the fact that masses, an occasional situation with a high number of visitors, are always held just before the church closes, it is guaranteed that carbon dioxide levels will never exceed the limit of 350 ppm above the outdoor values imposed by EN-13779, registering a maximum of 291 ppm.
Retrofitting Historic Buildings for Future Climatic Conditions and Consequences in Terms of Artifacts Conservation Using Hygrothermal Building Simulation Guilherme B. A. Coelho, Vasco Peixoto de Freitas, Fernando M. A. Henriques, Hugo Entradas Silva Applied Sciences Switzerland, 2023 Climate change will greatly influence the world at several levels and will have consequences on the interior climate of historic buildings and artifacts conservation. Buildings are responsible for a large slice of the overall emissions, which is due both to the greenhouse gases that are released during their construction as well as the activities that are performed therewithin. One way of counteracting this trend is to design more efficient retrofit buildings and predict their behavior using simulation software, which can thoroughly assess the performance of new buildings or the impact of each retrofit measure for existing buildings. In this study, a calibrated computational model of high thermal inertia building was used to assess the performance of passive retrofits in mitigating the effects of climate change concerning artifact decay mechanisms. In addition, a methodology that aims to reduce the amount of time spent to perform these studies is also presented, in which time savings reach up to 63%.
