Audit-Based Energy Performance Analysis of Multifamily Buildings in South-East Poland

Abstract

Multifamily buildings account for about half of all residential buildings in Poland and about 70% of the urban population live in them. Most of them require thermal refurbishment. Evaluation of a building’s energy performance with the use of correlation models has been very rarely used in relation to buildings in Poland. This method is simple, fast and can improve the decision process on thermal modernisation. It is especially important at the pre-design stage of planned investments. This paper presents an attempt to develop correlations that could be used in the energy assessment of multifamily buildings. For this purpose a dataset containing of 29 audits of multifamily buildings was used. The statistical analysis was performed for buildings before and after planned refurbishment. Obtained relationships showed strong correlation between thermal demand for space heating or domestic hot water and ventilation airflow and thermal transmittance of windows (R2 > 0.6). After designed modernisation the number of strong correlations decreased. Energy for domestic hot water was correlated with the number of inhabitants (R2 = 0.6). Energy for space heating was correlated with the number of users and heated volume of a building.

Ventilation Methods for Improving the Indoor Air Quality and Energy Efficiency of Multi-Family Buildings in Central Europe

“…Each of the 20 flats with varying degrees of use and the building as a whole were assessed. Many previous studies in this area were based mainly on static calculations [39,40], which did not take into account the instantaneous variability of the ventilation airflow in rooms on different floors of the building and the diversified schedule of occupancy, which did not allow for a reliable assessment of the instantaneous level of indoor air quality. Even if the calculations were carried out in dynamic external climate conditions, most studies assumed a constant infiltration air exchange during the year.…”

Methodology for Modernizing Local Gas-Fired District Heating Systems into a Central District Heating System Using Gas-Fired Cogeneration Engines—A Case Study

“…Another idea is to apply heat recovery from domestic hot water [9][10][11] or use novel heating systems [12][13][14] with phase-change materials (PCM) [15], heat pipes [16], or radiative systems [17]. Other effective ideas to decrease energy demand in buildings include using earth-to-air heat exchangers [18,19], applying heat pumps into ventilation units [20], incorporating an atrium as an HAVC (Heating Ventilation and Air Conditioning) element [21], or making complex energy audits [22,23], in addition to many others that result in better thermal comfort and lowered energy usage [24]. Legal requirements in the European Union require new erected buildings to be low-energy buildings that take care to ensure thermal comfort and indoor air quality [25].…”

Recent Achievements in Research on Thermal Comfort and Ventilation in the Aspect of Providing People with Appropriate Conditions in Different Types of Buildings—Semi-Systematic Review

“…Nevertheless, in the introduction, which is the background of the current review, it is impossible not to pay attention to the issues related to energy demand, which is the cost of maintaining high air quality and/or thermal comfort. Various technologies for heat recovery [2], or methods of intensifying heat exchange in system components [3][4][5], as well as the use of decentralized ventilation systems [6][7][8][9] or earth-to-air heat exchangers [10,11], positively affect the reduction in energy consumption in the energy audit of the building [12]. The energy-saving effect can also be obtained by using heat recovery from domestic hot water [13][14][15][16], but it is easier to achieve it in mechanical ventilation systems [17].…”