Issue 3/2022

The paper shows a simple case of the use of the ČSN EN 15316-4-8 standard, designed to evaluate the energy performance of gas appliances used to heat large premises. It opens a discussion on the possible problem of the calculation procedure with oversizing; since higher installed capacity is likely to lead to a lower energy consumption, it points out the possible illogical inclusion of the heat lost through the envelope of the appliance into the usable energy of the room. It also indicates possible calculation errors when choosing too long calculation interval, since all energy flows are aggregated within the time interval.

The paper focuses on the heat pump as a whole, in particular its acoustic directivity and recommendations for installation. In the conclusion, it presents an insight into the shortcomings of noise assessment and labelling of hea t pumps.

The paper maps and describes current approaches in the field of rainwater management. It discusses the different technical measures and solutions that are applied in this context. The aim is to create a comprehensive and clear set of measures in the field of rainwater management, to demonstrate the importance of this field in building practice with regard to environmental implications and other contexts, and to explain ho w buildings can be designed to make maximum use of rainwa ter.

The topic of the paper is a simulation analysis of a solar system for the preparation of hot water for an apartment building in two variants – centralized and decentralized. The analysis focuses on the impact of both variants on the overall energy consumption of hot water production. The results show that the usable solar heat gain and the year-round operating efficiency are similar for both variants of the solar system. However, the options differ substantially in solar fraction and auxiliary energy demand, due to the different values of the total annual hot wa ter energy demand.

The article reviews the historical sources available on the issue of school ventilation. It describes the approach to the ventilation of classrooms at the time more than 100 years ago, documented by citations of the regulations of the time. The paper provides historical requirements for the required ventilation airflow rate per pupil, which are derived mainly from metabolic CO 2 balance. Finally, the historical ventilation systems available at the time are described.

From 1st January 2020, all new buildings shall comply with a standard called Nearly Zero Energy Building (NZEB ), which imposes certain restrictions, particularly in relation to the configuration of the building technical systems. The definition of a near-zero energy building is given in Act No. 406/2000 Coll. by the general statement that it is a building with a very low energy performance whose energy consumption should be covered to a significant extent by renewable energy sources. The conditions for setting the parametric requirements for this standard are contained in the implementing Decree No. 264/2020 Coll., which defines the requirements for individual energy performance indicators. The subject of this paper is a comparison of the design of building technical systems in relation to the new requirements that are valid from 1 st Januar y 2022.