• Energy Research

The requirements concerning energy performance of buildings and their internal installations, particularly HVAC systems, have been growing continuously in Poland and all over the world. The existing, traditional calculation methods following from the static heat exchange model are frequently not sufficient for a reasonable heating design of a building. Both in Poland and elsewhere in the world, methods and software are employed which allow a detailed simulation of the heating and moisture conditions in a building, and also an analysis of the performance of HVAC systems within a building. However, these systems are usually difficult in use and complex. In addition, the development of a simulation model that is sufficiently adequate to the real building requires considerable time involvement of a designer, is time–consuming and laborious. A simplification of the simulation model of a building renders it possible to reduce the costs of computer simulations. The paper analyses in detail the effect of introducing a number of different variants of the simulation model developed in Design Builder on the quality of final results obtained. The objective of this analysis is to find simplifications which allow obtaining simulation results which have an acceptable level of deviations from the detailed model, thus facilitating a quick energy performance analysis of a given building.

The requirements concerning energy performance of buildings and their internal installations, particularly HVAC systems, have been growing continuously in Poland and all over the world. The existing, traditional calculation methods following from the static heat exchange model are frequently not sufficient for a reasonable heating design of a building. Both in Poland and elsewhere in the world, methods and software are employed which allow a detailed simulation of the heating and moisture conditions in a building, and also an analysis of the performance of HVAC systems within a building. However, these systems are usually difficult in use and complex. In addition, the development of a simulation model that is sufficiently adequate to the real building requires considerable time involvement of a designer, is time–consuming and laborious. A simplification of the simulation model of a building renders it possible to reduce the costs of computer simulations. The paper analyses in detail the effect of introducing a number of different variants of the simulation model developed in Design Builder on the quality of final results obtained. The objective of this analysis is to find simplifications which allow obtaining simulation results which have an acceptable level of deviations from the detailed model, thus facilitating a quick energy performance analysis of a given building.

Energy efficiency is extremely significant for industrial processes and technologies. Rising energy prices, depleting fossil fuels, as well as tightening regulations that impose the need to reduce GHG emissions incentivize companies to look for energy-efficient solutions. This also applies to wastewater treatment plants, which, on the one hand, are consumers of very large amounts of energy, and on the other hand, have significant potential to retrieve waste energy in the form of heat accumulated in wastewater. The authors of this publication have recognized the benefits of managing this heat. However, they have also pointed out several problems and difficulties associated with this process. By means of measured data, this publication provides a comprehensive analysis of the heat that can be recovered from wastewater treatment plants. As a result of the analyses, the locations of sites for collecting heat from wastewater have been determined, and potential technologies for this purpose have been identified. Moreover, the impact of the proposed heat recovery technology on the process of biological wastewater treatment has also been analyzed. As a result of the research, the authors developed generalized guidelines for selecting an optimal heat recovery site and the technological system designed for this purpose.

Energy efficiency is extremely significant for industrial processes and technologies. Rising energy prices, depleting fossil fuels, as well as tightening regulations that impose the need to reduce GHG emissions incentivize companies to look for energy-efficient solutions. This also applies to wastewater treatment plants, which, on the one hand, are consumers of very large amounts of energy, and on the other hand, have significant potential to retrieve waste energy in the form of heat accumulated in wastewater. The authors of this publication have recognized the benefits of managing this heat. However, they have also pointed out several problems and difficulties associated with this process. By means of measured data, this publication provides a comprehensive analysis of the heat that can be recovered from wastewater treatment plants. As a result of the analyses, the locations of sites for collecting heat from wastewater have been determined, and potential technologies for this purpose have been identified. Moreover, the impact of the proposed heat recovery technology on the process of biological wastewater treatment has also been analyzed. As a result of the research, the authors developed generalized guidelines for selecting an optimal heat recovery site and the technological system designed for this purpose.

In the EU countries, almost 50% of the produced energy is used in residential buildings. More than 25% of this energy is used to produce domestic hot water, of which almost 80% is used to heat water in domestic hot water circulation systems. This is due to high expectations on the part of residents based on their comfort, in particular regarding the supply of heat for heating and domestic hot water. In the course of their long-term research conducted on real systems, the authors confirmed that the operation of domestic hot water distribution systems causes significant costs, mainly due to heat losses. Therefore, typical variants of energy optimization of such systems were analyzed. Tests have shown that selected solutions, such as the use of control automation, are not sufficient, and recommended additional thermal insulation may not be applicable due to technical reasons. With an aim of finding a solution to the problem, the publication analyzes operational data from an existing heat source and domestic hot water circulation system in a residential building. On the basis of these analyses, a solution was proposed to reduce energy consumption within the installation by means of its hydraulic optimization. The reduction of heat losses in domestic hot water installation by means of a method presented by the authors is estimated at approximately 20%.

In the EU countries, almost 50% of the produced energy is used in residential buildings. More than 25% of this energy is used to produce domestic hot water, of which almost 80% is used to heat water in domestic hot water circulation systems. This is due to high expectations on the part of residents based on their comfort, in particular regarding the supply of heat for heating and domestic hot water. In the course of their long-term research conducted on real systems, the authors confirmed that the operation of domestic hot water distribution systems causes significant costs, mainly due to heat losses. Therefore, typical variants of energy optimization of such systems were analyzed. Tests have shown that selected solutions, such as the use of control automation, are not sufficient, and recommended additional thermal insulation may not be applicable due to technical reasons. With an aim of finding a solution to the problem, the publication analyzes operational data from an existing heat source and domestic hot water circulation system in a residential building. On the basis of these analyses, a solution was proposed to reduce energy consumption within the installation by means of its hydraulic optimization. The reduction of heat losses in domestic hot water installation by means of a method presented by the authors is estimated at approximately 20%.