Design, Project, and Realization of a Prototype of an Energy-efficient Prefabricated House IDA I. using Renewable Energy Sources

In this paper, we describe our experience with the design, project, and implementation of a prototype of an energy-efficient prefabricated house IDA I. using renewable energy sources (RES). This prototype is the result of our research in the field of energy (solar) roofs, ground heat storages, and active thermal protection. The client of the applied research, the owner of the prefabricated plant, has purchased the license for the patented ISOMAX system. Experience from the implementation of buildings according to this system shows the high potential using of RES but also the shortcomings caused by the variable, unstable, hardly predictable solar and geothermic energy stored in ground heat storages. The production of panels ISOMAX in the lost form from expanded polystyrene was too complicated, time-consuming, and often showed problems from a static point of view. Our research aimed to design an innovative, original, and reliable mode of operation for the IDA I. prefabricated house prototype under development, which in synergy with the building management system, will optimize the mode of operation of all heat/cooling sources and energy systems. Another task was to innovate the design of the envelope panel with active thermal protection, eliminate the shortcomings of the technical design of the ISOMAX panel, and adapt as many components as possible to prefabrication. The prototype of the energy-efficient prefabricated house IDA I. using RES represents an innovative energy-secure and self-sufficient construction option compared to buildings with fossil fuel-based heating/cooling sources

Parametric study of the energy potential of a building’s envelope with integrated energy-active elements

Building structures with integrated energy-active elements (BSIEAE) present a progressive alternative for building construction with multifunctional energy functions. The aim was to determine the energy potential of a building envelope with integrated energy-active elements in the function of direct-heating, semi-accumulation and accumulation of large-area radiant heating. The research methodology consists in an analysis of building structures with energy-active elements, creation of mathematical-physical models based on the simplified definition of heat and mass transfer in radiant large-area heating, and a parametric study of the energy potential of individual variants of technical solutions. The results indicate that the increase in heat loss due to the location of the tubes in the structure closer to the exterior is negligible for Variant II, semi-accumulation heating, and Variant III, accumulation heating, as compared to Variant I, direct heating, it is below 1 % of the total delivered heat flux. The direct heat flux to the heated room is 89.17 %, 73.36 %, and 58.46 % of the total heat flux for Variant I, Variant II and Variant III, respectively. For Variant II and Variant III, the heat storage accounts for 14.84 %, and 29.86 % of the total heat flux, respectively. Variants II and III appear to be promising in terms of heat/cool accumulation with an assumption of lower energy demand (at least 10 %) than for low inertia walls. We plan to extend these simplified parametric studies with dynamic computer simulations to optimise the design and composition of the panels with integrated energy-active elements

Heat Recovery Variable Refrigerant Volume System Installation and Experiences from its Summer Operation

Variable refrigerant volume (VRV) systems operate on the principle of a cooling machine. They extract heat from one side and return it on the other, enabling them to function as a source of heat for both heating and hot water preparation, as well as a source of cold for cooling within a single building. These systems efficiently remove unnecessary excess heat outside and only introduce the required amount of heat from the outside into the building. With an appropriate configuration and setting, a VRV system can transfer heat in both directions within one system, eliminating the requirement for waste heat to be removed without use in the building. Instead, it is transferred to the desired locations where it is needed. This principle necessitates the adjustment of not only the refrigerant temperature but also its flow rate. Consequently, the VRV system can fulfil tasks that are otherwise handled by several individual systems in a building.A heat recovery VRV system was installed in a small retail store to extract waste heat generated by baking ovens during the baking process. This report provides a brief summary of electricity and energy consumption measurements taken during the summer period for cooling purposes. Sequential logic is observed and coherence is ensured, with active voice predominating for clearer and more direct communication. The parameters of interest include cooling setpoints, cooling outside of working hours, and capacity assessment

Parametric study of the energy potential of a building’s envelope with integrated energy-active elements

Building structures with integrated energy-active elements (BSIEAE) present a progressive alternative for building construction with multifunctional energy functions. The aim was to determine the energy potential of a building envelope with integrated energy-active elements in the function of direct-heating, semi-accumulation and accumulation of large-area radiant heating. The research methodology consists in an analysis of building structures with energy-active elements, creation of mathematical-physical models based on the simplified definition of heat and mass transfer in radiant large-area heating, and a parametric study of the energy potential of individual variants of technical solutions. The results indicate that the increase in heat loss due to the location of the tubes in the structure closer to the exterior is negligible for Variant II, semi-accumulation heating, and Variant III, accumulation heating, as compared to Variant I, direct heating, it is below 1 % of the total delivered heat flux. The direct heat flux to the heated room is 89.17 %, 73.36 %, and 58.46 % of the total heat flux for Variant I, Variant II and Variant III, respectively. For Variant II and Variant III, the heat storage accounts for 14.84 %, and 29.86 % of the total heat flux, respectively. Variants II and III appear to be promising in terms of heat/cool accumulation with an assumption of lower energy demand (at least 10 %) than for low inertia walls. We plan to extend these simplified parametric studies with dynamic computer simulations to optimise the design and composition of the panels with integrated energy-active elements

Experience in Researching and Designing an Innovative Way of Operating Combined Building–Energy Systems Using Renewable Energy Sources

This study describes our experience in researching and designing an innovative way of operating combined building–energy systems using renewable energy sources. We used the concepts of the ISOMAX integrated building–energy system’s patented technical solution, which we have long been exploring and have developed various novel and original solutions, as inspiration for our research. A consistent peak heat/cooling supply is a key component of the patented ISOMAX system, which has also been proven in its use in many buildings. Energy systems are no longer dependent on unreliable, unpredictable, and hard-to-forecast geothermal and solar energy because of the peak energy source. We had to improve the original design to guarantee the efficient, comfortable, and dependable operation of all the energy systems in the building. We increased the capacity of the ventilation system by including a peak heat/cooling source, a short-term heat/cooling storage tank, and the option of using an air handling unit with heat recovery or a water/air heat exchanger. The addition of terminal elements for heating, cooling, and ventilation systems was also made, along with including a solar system, a wind turbine, and the potential for waste heat recovery. Our study led to the creation of a unique operating model that, with the building management system, optimizes all of the energy systems and heating/cooling sources. The utility model SK 5749 Y1 analyzes the various alternatives in great detail

Contribution to Active Thermal Protection Research—Part 2 Verification by Experimental Measurement

This article is closely related to the oldest article titled Contribution to Active Thermal Protection Research—Part 1 Analysis of Energy Functions by Parametric Study. It is a continuation of research that focuses on verifying the energy potential and functions of so-called active thermal protection (ATP). As mentioned in the first part, the amount of thermal energy consumed for heating buildings is one of the main parameters that determine their future design, especially the technical equipment. The issue of reducing the consumption of this energy is implemented in various ways, such as passive thermal protection, i.e., by increasing the thermal insulation parameters of the individual materials of the building envelope or by optimizing the operation of the technical equipment of the buildings. On the other hand, there are also methods of active thermal protection that aim to reduce heat leakage through nontransparent parts of the building envelope. This methodology is based on the validation of the results of a parametric study of the dynamic thermal resistance (DTR) and the heat fluxes to the interior and exterior from the ATP for the investigated envelope of the experimental house EB2020 made of aerated concrete blocks, presented in the article “Contribution to the research on active thermal protection—Part 1, Analysis of energy functions by the parametric study”, by long-term experimental measurements. The novelty of the research lies in the involvement of variant-peak heat/cooling sources in combination with RES and in creating a new, original way of operating energy systems with the possibility of changing and combining the operating modes of the ATP. We have verified the operation of the experimental house in the energy functions of thermal barrier, heating/cooling with RES, and without RES and ATP. The energy saving when using RES and ATP is approximately 37%. Based on the synthesis and induction of analogous forms of the results of previous research into recommendations for the development of building envelopes with energy-active elements, we present further possible outcomes in the field of ATP, as well as already realized and upcoming prototypes of thermal insulation panels