Issue 4/2022

In 1902, the councillors of Královské Vinohrady, then an independent part of Prague, decided to build a large stone theatre. In 1907 the theatre was inaugurated. The paper briefly introduces history and the cultural and political development of the theatre and mainly focuses on the technical systems of the building – heating and ventilation. Following the preserved technical documentation, the author describes the original system of hot-air heating and ventilation of the main areas of the theatre – the auditorium and the stage. According to the documentation and his own research, the author describes the heating system, the location and relocation of the coal boiler room, and the transition to gas heating. He also discusses the changes in the ventilation system that have taken place over the years. This also covers the more recently designed air conditioning equipment tha t is no longer in use today . To improve the thermal comfort in the indoor environment, a central source of cold was added to the building during the 1994 renovation; it was intended to cool only the supply air to the auditorium area. Separate split cooling units were installed for some of the smaller rooms. The paper is accompanied by photographs of the old and new equipment, including the air supply solution respecting the interior design.

The subject of the paper is the design and description of an unconventional concept of an energy and environmental system of a building. Theoretical background and motivation for system design are established and introduced. Subsequently, the system is presented in two variants, levels, which address the building rainwater management, cooling, and, optionally, building heating and hot water production. Consequently, the results of the basic balance calculation are presented, using a case study example to determine the usability of the proposed system.

The first part of the contribution presents the theoretical part of the design of an operation control for an autonomous electricity and heat generation system. The system consists of a Wave ORC cogeneration unit, photovoltaic panels, battery storage and a virtual heat storage. The whole system is located at the University Centre for Energy Efficient Buildings of the Czech Technical University in Prague. The aim of the control is to minimize the purchase and sale of electricity from the distribution grid and to maintain the supply of heat and electricity with the highest possible efficienc y of the whole system.

There are technical solutions that allow periodic access to forecasted climatic variables, such as ambient air temperature, relative humidity, wind speed and wind direction. Solar radiation data are not yet routinely provided by weather forecast. The aim of this paper is to describe a method for estimating daily solar irradiation from available weather forecast data. The proposed calculation model uses a strong relationship between the daily global solar irradiation and the difference between the daily minimum and the maximum ambient air temperature. The unknown parameters of prediction models were searched by means of mathematical optimization methods. The comparison with measured global solar irradiation showed a relatively high degree of agreement with a relative error very often less than 10 % in the warm season of the year. The method used for conversion of the predicted global solar irradiation on the horizontal plane to global solar irradiation on vertical oriented planes did not lead to such a good a greement with measured da ta.

This article sums up the technical and the normative conditions of fire protective systems to insure the fire resistance of air ducts and the smoke extraction ducts. It analyses the fire scenarios defined by the test standards and shows the typical fire protection examples found in practice. The paper aims not only at the HVAC designers but also a t designers in rela ted disciplines.

The paper presents different approaches to the evaluation of positive energy districts. One hundred Positive Energy Districts (PED s) should be implemented in the EU by 2025. There are already three cities in the Czech Republic that are currently working on proposals for a PED project. So far, the focus in Europe has been on building energy, mainly in the context of individual buildings with nearly zero energy consumption. However, a clear trend can be seen in European research projects of a shift from single building solutions to energy concepts for entire city districts. Although the definition of PED has not been yet well established in any European legislation, there are several different approaches to assessing the level of use of renewable energy in an urban neighbourhood. An analysis of the approaches to determine the positive energy balance is carried out for a set of residential buildings and the impact of the definition on the design of the energ y concept is evalua ted.