Issue 6/2020

Nowadays, double-skin facades represent a distinctive architectural element in modern buildings. However, their real thermal impact on the overall building energy performance can be enhanced by the facades internal modifications. The main modifications include the dimensions of the facade cavity, the intensity of the solar radiation, the combination of the optical parameters of both the transparent and opaque parts, as well as the possibility to have a natural or forced air flow movement in the cavity. The presented paper is focused on the quantification of the different levels of the above-mentioned factors as the boundary conditions for the thermal performance of the air flo w movement in the facade ca vity through its overall height.

The paper presents the potential of using vegetation for improving the indoor air quality. The influence of plants is investigated on an experimental element with greenery, which was designed as a dividing element in large offices with the condition of the minimum necessary maintenance. The article presents the proposed element and the results of measuring the basic parameters of the indoor environment (temperature, relative humidity, concentration of carbon dioxide, light intensity and air velocity) inside the element. At the end of the article, other possibilities are also summarised for its a pplication.

The contribution is aimed at the hygrothermal interaction of an indoor climate with an original mural painting in the Romanesque Rotunda in Znojmo. This hygrothermal interaction has been analysed through impact of the heating, ventilation, and number of visitors on the indoor climate with the subsequent impact on the mural painting. This triple parametrical numerical simulation was performed in the WUFI®Plus 3.0 software and independently in the BSim 2000 software and CalA 4.0 software. The numerical simulation of the indoor climate is validated with real long-term measurements from 2011 – 2015 in hourly time steps. A correlation of 99 % was obtained for the WUFI®Plus 3.0 software with the BSim 2000 software for the indoor climate and a correlation of 97 % was obtained for the hygrothermal diffusion in the peripheral wall with the CalA 4.0 software. The obtained results show that a thermal stress up to 2.6 K and a dryness effect up to 18.3 kg/m3 caused by the intensive heating act on the mural painting. A thermal stress up to 1.4 K and a dryness effect up to 26.8 kg/m3 was also obtained by the intensive ventilation on the mural painting. This obtained knowledge shows that a natural indoor climate in combination with conservation heating should be preferred over a controlled indoor c limate in the Romanesque Rotunda in Znojmo.

In the majority of cleanroom applications, the thermal environment is overshadowed by the contamination control as a priority. As a consequence, the cleanroom users are likely to experience a lower thermal comfort. This study investigated the thermal environment of six research laboratories designed and operated as cleanrooms with the class of cleanliness ISO 5 or ISO 7. A comparison of the various classes of cleanliness and the different air distribution systems enabled the complex analysis in order to determine the issues of the thermal environment. Apart from the calculation of the PMV and PPD indexes, the vertical air temperature difference, risk of draught and homogeneity of the local conditions were also examined. Based on the results, cleanroom users are often exposed to conditions unsuitable for their well-being. The specific requirements of cleanrooms frequently result in high air velocities and inconvenient temperatures that are not tied to the activity and c lothing levels of the users.

A vast energy consumption database is available in the framework of the research project entitled “Large Scale Smart Meter Data Assessment for Energy Benchmarking and Occupant Behaviour Profile Development of Building Clusters”. The database contains consumption data for approximately 10,000 buildings. Amongst the smart metered buildings, there are both residential and non-residential types. This research aims to identify different consumer groups and energy consumption profiles for various building types. For this study, a small sample was selected, which includes 76 school buildings. The energy consumption data are examined by using different clustering techniques: K-means, Fuzzy K-means, and Agglomerative Hierarchical Clustering Methods. In this artic le, the current sta te of our research is summarised.

The combustion of fuels, especially non-renewable ones, is associated with the systematic emissions of harmful substances into the atmosphere, which, in turn, adversely affects the quality of the environment and human health, deteriorates the condition of ecosystems and leads to negative climate changes. The aim of the work is to calculate the expected ecological effects of measures, aimed at reducing the energy demand for existing residential buildings, to a level corresponding to the requirements for the thermal protection of buildings in Poland. It has been estimated that, as a result of reducing the energy consumption for heating in buildings to the level of 65-70 kWh/(m2year), over 70 % in energy savings can be achieved compared to 2011. This will result in a general reduction of pollutant emissions of nearly 70 %. A comparison was made of low low-stack emission reduction when using modern boilers fuelled by various energy carriers (hard coal, wood, natural gas, heating oil) in an educational building. The renewable energy potential of the European Union was also presented. The possibility of using renewable energy sources are illustrated, including an example of the use of geothermal wa ter for hea ting public buildings.