Issue 3/2022

Keywords: new generation district heating, low temperature networks, energy efficiency

Abstract
The paper outlines the characteristics of the stages of technological development of district heating systems to this day and age, highlighting the key concepts that the state-of-the-art fourth-generation district heating systems are based on. It concerns the issues of reducing the temperature in district heating networks, as well as the use of low-temperature district heating networks, showcasing the potential advantages of this solution, in addition to technical challenges to be solved. Upgrading the existing district heating systems to the fourth-generation standard will lead to increasing the number of local renewable energy sources and waste heat recovery systems, which in turn is going to increase the stability of heat prices and improve the safety of heat supply. The paper indicates that low-temperature district heating systems are viewed as an up-and-coming innovative solution with great potential to replace the existing district heating systems.

Keywords: district heating systems, project, qualitative risk assessment

Abstract:
This article is inspired by the problems faced by the heating sector in the face of transformational changes that we have witnessed recently. The implementation of the goals in the field of heating transformation requires the introduction of many new investments aimed at improving the quality of heating systems functioning, and thus the living conditions. The aim of the work is to review the issues related to the risk of investment projects along with the analysis and assessment of potential risks that may occur in investment projects in the heating sector. An integral part of the work is the selection of the most optimal and useful risk measurement methods, thanks to which the heating company will be able to eliminate the given risks at source or reduce their size to an acceptable level. The risk analysis of investment projects is shown on the example of a real investment project, which is currently being implemented by a district heating company. The analysis was based on the experiences gained in coordinating project implementation in the district heating sector and managing a team implementing projects co-financed from EU funds.

Keywords: Forecast control, Forecasting heat consumption, Building energy model, Control of heating, Energy efficiency in existing buildings, Smart buildings

Abstract
Energy efficiency in existing and new buildings is an important issue in view of the need to achieve carbon neutral buildings in the near future. One option to increase the energy efficiency of existing buildings is to use predictive control of the heating system. However, there is still no simple and easy-to-use method that implements forecast control taking into account internal and external factors. Therefore, this article presents the first part of information on a simple to apply in existing buildings method of forecast control of a heating system. In particular, the process of installing the proposed forecast control system in buildings (installation time less than 2 hours) and creation of building energy model (including its heating system) in the form of an equivalent outdoor temperature was presented. The second part of the article (planned in the issue 7-8/2022) will contain information on the implementation of the forecast control process and the energy savings for heating.

SAbstract
Article is systematizing information concerning: principles for introducing or/and make available materials and construction products on the domestic market, declaration of the performance for products with construction marking, national declaration of performance of construction products and national declarations of performance for pre-insulated pipes and joints.

Keywords: compressor heat pump, design, principle of operation, performance coefficients

Abstract
The test subject was a WPC 13 compressor brine/water heat pump with a heating capacity of 13.2 kW. The test site was located in a single-family building with a total area of 340 m2 [1]. The heat pump was adapted to cooperate with a low-temperature heat exchanger, which was a water tank located next to the building. The construction and principle of operation of compressor heat pumps, their classification and basic parameters as well as the applied construction solutions in relation to the bottom heat sources are presented.