Search Results (338)

With growing community awareness of greenhouse gas emissions and their environmental consequences, distributed rooftop photovoltaic (PV) systems have emerged as a sustainable energy alternative in residential settings. However, the high penetration of these systems without effective operational strategies poses significant challenges for local distribution grids. Specifically, the estimation of surplus energy production from these systems, closely linked to complex outdoor weather conditions and seasonal fluctuations, often lacks an accurate forecasting approach to effectively capture the temporal dynamics of system output during peak periods. In response, this study proposes a recurrent neural network (RNN)- based forecasting framework to predict rooftop PV surplus in the context of micro-residential communities over time horizons not exceeding 48 h. The framework includes standard RNN, long short-term memory (LSTM), bidirectional LSTM (BiLSTM), and gated recurrent unit (GRU) networks. In this context, the study employed estimated surplus energy datasets from six single-family detached houses, along with weather-related variables and seasonal patterns, to evaluate the framework’s effectiveness. Results demonstrated the significant effectiveness of all framework models in forecasting surplus energy across seasonal scenarios, with low MAPE values of up to 3.02% and 3.59% over 24-h and 48-h horizons, respectively. Simultaneously, BiLSTM models consistently demonstrated a higher capacity to capture surplus energy fluctuations during peak periods than their counterparts. Overall, the developed data-driven framework demonstrates potential to enable short-term smart energy scheduling in micro-residential communities, supporting electric vehicle charging from single-family detached houses through efficient rooftop PV systems. It also provides decision-making insights for evaluating renewable energy contributions in the residential sector. Full article

Residential space heating in Northern Europe requires long-duration thermal storage to align summer solar gains with winter heating demand. This study investigates a compact sand-based seasonal thermal energy storage integrated with flat-plate solar collectors for an A+ class single-family house in Kaunas, Lithuania. An iterative co-design couples collector sizing with the seasonal charging target and a 3D COMSOL Multiphysics model of a 300 m³ sand-filled, phenolic foam-insulated system, with a 1D conjugate model of a copper pipe heat-exchanger network. The system was charged from March to September and discharged from October to February under measured-weather boundary conditions across three consecutive annual cycles. During the first year, the storage supplied the entire winter heating demand, though 35.2% of the input energy was lost through conduction, resulting in an end-of-cycle average sand temperature slightly below the initial state. In subsequent years, both the peak sand temperature and the residual end-of-cycle temperature increased by 3.7 °C and 3.2 °C, respectively, by the third year, indicating cumulative thermal recovery and improved retention. Meanwhile, the peak conductive losses rate decreased by 98 W, and cumulative annual losses decreased by 781.4 kWh in the third year, with an average annual reduction of 4.15%. These results highlight the progressive self-conditioning of the surrounding soil and demonstrate that a low-cost, sand-based storage system can sustain a complete seasonal heating supply with declining losses, offering a robust and scalable approach for residential building heating applications. Full article

Intensive development of recreational construction has taken place in the Beskid Mountains in Southern Poland over the span of several decades, especially in the villages of Szczyrk, Wisła, and Brenna, due to the proximity of the industrial Silesian agglomeration. These buildings, constructed mostly since the 1970s, are heterogeneous in appearance and often do not reference traditional timber-and-stone sustainable architecture; instead, they replicate the esthetics found in contemporary single-family houses throughout Poland or abroad. Inconsistencies in building regulations have reinforced this approach, leading to a decline in the quality of both architecture and landscape. Although this situation has been widely discussed in public media, publications on this topic remain sporadic. This article therefore applies qualitative research to discuss the role of cultural identity in modern recreational architecture in the Beskid Mountains as it has affected the well-being of the citizens of Silesia since the 1930s. The unique contribution of this paper to Polish architectural and heritage research is threefold: it provides a structured framework for understanding the development of recreational architecture as a process, it explicitly links empirical field observations to theoretical frameworks (Frampton, Norberg-Schulz, Rapoport), and it proposes a general pathway for culturally sustainable design in the region. Full article

The EPBD 2024 recast sets the deadline for new Zero-Emission Building standards for all new publicly owned buildings to 2028 and to 2030 for all new buildings. In the scope of Life Cycle Assessment stages, all steps resulting in major emissions from buildings must be considered and presented. The research evaluates the life cycle greenhouse gas emissions of a single-family house, focusing on diverse construction types and the hourly method of the annual energy calculations for continental and coastal climate areas in Croatia under the upcoming standards. Embodied carbon of diverse construction types was compared mutually, and required steps to meet the operational zero-emission standards were analyzed. Embodied energy of a 137.0 m² family house built out of reinforced concrete results in up to 67 tons of CO₂eq emissions, while wood in cross-laminated timber structures absorbs more carbon than emitted for all other materials and construction processes—23 tons of CO₂eq. Regarding operational energy and accompanying emissions, in order to cost-effectively meet future ZEB standards in Croatia and offset the remaining operational emissions, photovoltaic systems of up to 2.5 kWp are required in continental areas and 1.6 kWp in coastal regions. Full article

This study evaluates the operational performance and carbon emissions of an air-source heat pump (ASHP) system based on a one-year field monitoring campaign conducted at a single-family detached house in Gongju, South Korea. The system, equipped with a 9 kW air-to-water ASHP, supplied both space heating (SH) and domestic hot water (DHW), achieving average coefficients of performance (COPs) of 2.27 for SH and 2.06 for DHW. To estimate nominal COPs, a bi-quadratic regression model was developed using manufacturer catalog data and compared against field measurements. The analysis revealed a significant performance decline during winter: a paired t-test using 7119 samples confirmed a statistically significant discrepancy under low-temperature conditions. Annual CO₂-equivalent (CO₂eq) emissions were also evaluated. Under current grid emission factors, the ASHP system emitted 1532 kgCO₂eq—approximately 8.6% more than a condensing gas boiler (1411 kgCO₂eq), primarily due to winter performance degradation and the relatively high carbon intensity of electricity. These findings underscore the importance of incorporating actual operating conditions, seasonal variability, and the national electricity emission factor when assessing ASHP performance and life cycle climate performance (LCCP). Full article

The research process was based on an analysis of an existing building equipped with a heat pump on which photovoltaic panels were installed; then, based on energy consumption, the investment profitability was evaluated. In this research, using the available data, the coefficient of self-consumption of energy from the PV installation, the potential index of the installation’s own needs coverage, and the index of energy use from photovoltaic modules were determined, which in practice is equated with the energy efficiency of the PV installation. The entire investment was subjected to simulation and field tests to determine the energy demand of a single-family building. The main aim of this work was to check whether a system equipped with a heat pump combined with a PV installation is an effective technical solution in the analysed climatic conditions in one of the countries of Central and Eastern Europe. In addition, both positive and negative aspects of renewable energy sources were analysed, including long-term financial savings, energy independence, and reductions in greenhouse gas emissions. It has been shown that the described solution is characterised by high initial costs depending on weather conditions. The installation presented would allow us to avoid 1891 kg/year of CO₂ emissions, which means that with this solution, we contribute to environmental protection activities. Full article

In recent years, European cities have experienced rapid changes in their functional and spatial organisation, which have affected, among others, the natural environment, the economy and society. The intensive and often uncontrolled growth of residential development associated with suburbanisation significantly impacts areas located around urban areas. Growing investment pressures usually lead to the transformation of rural and naturally valuable areas, altering their character and functions. Solving these problems requires developing a method to determine the main directions and intensity of land use changes in the context of urbanisation pressures and sustainable spatial development. This article presents the results of a spatiotemporal analysis of the dynamics of built-up area development in rural and suburban zones, utilising Geographic Information Systems (GIS) technology. The study focused on the expansion of single- and multi-family housing around the city of Białystok, Poland, between 1997 and 2022. The analysis was based on spatial data, including available orthomosaics and cadastral data from the Topographic Objects Database (BDOT10k). The GIS-based analysis covered an area of nearly 2000 km² and included methods for change detection, analysis, and land cover classification. The results indicated a marked intensification in landscape transformations, particularly in transition zones between rural and urban areas. At the same time, forests and protected zones significantly influenced the direction and pace of development, acting as natural barriers limiting spatial expansion. The results indicate the need to consider environmental factors (e.g., protected areas and forests) in spatial planning processes and sustainable development policies. The study confirms the high usefulness of GIS tools in monitoring and forecasting spatial change at both the local and regional scales. This research also contributes to the discussion on urbanisation, its characteristics, causes, and consequences, and highlights the role of green spaces in limiting sprawl. Full article

The integration of smartphone-powered Virtual Reality (VR) into architectural practice is transforming how unbuilt spaces are perceived. The presented study is based on ten single-family house projects in which immersive visualization was introduced through mobile VR headsets connected to Building Information Modeling (BIM). It should be treated as a pilot study, preceding further comprehensive research on the subject. A total of 23 participants (investors and future users of the buildings at the same time) were actively involved in the design process supported by VR technology. Field of view adjustment was implemented within the BIM + VR model to align the virtual perception with the natural human visual range, improving the realism of the experience. Preliminary findings indicated that VR walkthroughs enhanced the future users’ understanding of spatial arrangements and supported informed decision-making. Over 80% of participants reported that it helped them better assess room sizes, placement of windows and doors, and furniture layout. This improved communication between investors and designers, and reduced the number of revisions required at further design stages. The use of VR to merge architecture with interior design enabled a human-scale perspective, cost optimization, and the exploitation of BIM + VR visualization potential for sustainable residential design. Full article

The economic benefit of a 12.8 kWp photovoltaic (PV) system was calculated using real consumption and electricity generation data for a typical modern single-family house in Sweden for the six years between 2019 and 2024. Electricity trade prices were based on the local spot market plus taxes and fees. The effect of a tax reduction on exported electrical energy was evaluated. The economic benefit was simulated for the case of a virtual AC-coupled battery added to the house using a charging strategy to maximize the self-consumption of the house. Additionally, the economic benefit was simulated for a range of different yearly consumptions and PV system sizes. The calculation shows that the PV system alone can be economically beneficial, while adding a battery with typical investment prices from 2025 does not pay off if it is only used to increase the self-consumption rate. Full article

The solar energy reaching the immediate surroundings of a single-family house throughout the year is sufficient to repeatedly and fully cover its heating needs during the heating season in a temperate climate. Nevertheless, modern technology is not yet able to fully solve the problem of thermal self-sufficiency in single-family houses. It is therefore advisable to seek solutions that improve the thermal efficiency of domestic solar installations. Efficient use of solar radiation heat accumulated during the summer months for heating requires the use of high-volume storage tanks. Another option is to discharge excess heat outside the system during the summer. This publication focuses on the latter solution. A model of the solar heating system for a residential building and pool with a storage tank powered by solar energy has been developed. Simulation calculations were performed, showing that the removal of excess heat is a beneficial solution, especially when this energy can be used to heat water in the pool. The calculations concerned the heating of a single-family house in a temperate climate. Lowering the temperature of the water in the storage tank reduces heat losses from the tank to the environment (ground), while supplying the solar collectors with lower-temperature fluid increases the driving force of the heat transfer process. Full article

The transformation of energy systems towards low emission is one of the key assumptions of the climate and energy policy of the European Union and many countries around the world. These changes include not only the power and transport sectors but also the heating of residential buildings, which consume significant amounts of energy and emit large amounts of greenhouse gases. This article presents a detailed comparative analysis of the costs of heating using an air-to-water heat pump and a condensing gas boiler. The study concerned a retrofitted single-family building from the 1990s, located in southern Poland. The calculations were made taking into account daily meteorological data for two full heating seasons: 2022/2023 and 2023/2024. This approach made it possible to more precisely reproduce real operating conditions. The study was conducted for various configurations of the central heating system: surface and radiator. The following parameters were also taken into account: (1) variable heat pump parameters, such as supply temperature LWT and coefficient of performance COP; (2) current tariffs for electricity and natural gas; and (3) forecasted tariffs for electricity and natural gas in the conditions of market liberalization and phasing out of protective mechanisms. A comparison of the two heating seasons revealed lower costs with a heat pump. In some cases, the cost of heat generated by a gas boiler was over 100% higher than with a heat pump. This applies to both heating seasons. Under the current tariffs, the calculated gas cost for the first season was PLN 6856 (EUR 1605) (1 EUR = 4.27 PLN) compared to heat pump heating costs ranging from PLN 3191 to PLN 4576 (EUR 747 to 1072). For future gas and electricity tariffs, the costs were PLN 8227 (EUR 1926) for gas and PLN 3841 to PLN 5304 (EUR 899 to 1242) for a heat pump. Similarly, for the second heating season, these values were PLN 6055 (EUR 1418) for gas heating and PLN 2741–3917 (EUR 642–917) for a heat pump under the current tariffs, and PLN 7267 (EUR 1702) and PLN 3307–4540 (EUR 774–1064) under future tariffs. This means percentage savings of between approximately 33% and 55%, depending on the heating type and tariff. Therefore, the obtained results indicate the higher profitability of using an air heat pump compared to a gas boiler. This advantage was maintained in all the discussed scenarios, and its scale depended on the type of installation, supply temperature, and the selected electricity tariff. The highest economic profitability was noted for low-temperature systems. These results can provide a basis for making rational investment and design decisions in the context of the energy transformation of single-family housing. Full article

Advancements in material technologies and increasingly stringent thermal insulation requirements are driving the search for innovative solutions to serve as an alternative to traditional insulating materials. Using 3D printing techniques to produce thermal insulation opens up new possibilities for creating structures, geometries, and shapes from a variety of raw materials, ranging from synthetic polymers to biodegradable composites. This study aimed to develop a modern thermal insulation barrier with a comparable thermal conductivity to conventional materials to enhance the energy efficiency of buildings. Cellular materials based on the Kelvin cell were fabricated using additive manufacturing via 3D SLS printing from a composite consisting of a biodegradable material (TPS) and a recyclable polymer (PA12). The printed cellular structural partitions were tested for their thermal insulation properties, including thermal conductivity coefficient, thermal transmittance (U-value), and thermal resistance. The best thermal insulation performance was demonstrated by a double-layer partition made from TPS + PA12 at a mass ratio of 5:5 and with a thickness of 60 mm. This sample achieved a thermal conductivity of λ = 0.026 W/(m·K), a thermal resistance of R = 2.4 (m²·K)/W, and a thermal transmittance of U = 0.42 W/(m²·K). Cellular partition variants with the most favorable properties were incorporated into building thermal balance software and an energy simulation was conducted for a single-family house using prototype insulating materials. This enabled an assessment of their energy efficiency and cost-effectiveness. Full article

Long-term renovation strategies (LTRSs) play a central role in achieving the European Union’s objective of a climate-neutral building stock by 2050. In Poland, the challenge is particularly acute: a majority of the building stock was constructed before 1990 and does not even meet basic thermal performance standards. In view of the state of the buildings in Poland and the assumptions made about obtaining the necessary energy parameters in the coming years, it is necessary to undertake thermal modernization measures. The purpose of the paper is to assess the economic efficiency of the variants of modernization of building stock in Poland, taking into account the constraints related to improving energy efficiency. Additionally, the article also points out the problem of discrepancies resulting from climate zones that may significantly affect the final primary energy results (on average, 5–15%). In order to achieve the objectives, the paper focuses on the analysis of energy sources. According to the overall score in the analytic hierarchy process (AHP) method, the best solutions, with a global priority of 0.46, are renewable energy sources (RESs). The evaluation of selected fuel types in the 2055 perspective, using the technique for order preference by similarity to ideal solution (TOPSIS) method, indicate favorable environmental performance by sources based on electricity, i.e., air-source heat pumps, ground-source heat pumps, and electric heating, which achieved the highest relative closeness to the ideal solution. Heat pump systems can reduce energy consumption by 26–41% depending on the building and heat pump type. The final analysis in the paper concerns different options for thermal modernization of a model single-family house, taking into account different energy sources and stages of thermal modernization work. The scenario involves the simultaneous implementation of all renovation measures at an early stage, resulting in the lowest investment burden over time and the most favorable economic performance. Full article

Many countries worldwide are facing a housing crisis, marked by a shortage of affordable housing. To respond to this growing crisis, prefabricated residential construction is gaining popularity due to cost savings in mass production, faster construction times, improved quality control, and sustainability considerations. This study provides a critical review of the available literature within the prefabricated and modular residential construction industry to assess its present status and to identify opportunities and challenges. The literature was categorized into the subfields of architecture, sustainability, structural, energy, environment, factory build, installation, policy, possibilities and challenges, and case studies. A detailed summary is provided for each subfield. This study aims to provide insights into the prefabricated and modular residential construction industry to fill the knowledge gap, discover possibilities, and address any challenges to create a clear pathway for implementation. Full article

Hybrid ventilation is indicated as one of the effective methods of maintaining thermal comfort and indoor air quality and reducing energy consumption in buildings. It assumes the capacity to switch between natural and mechanical ventilation, allowing the most efficient use of the outdoor air potential. This article aims to quantify the impact of changing ventilation system, from natural to hybrid, on indoor air parameters and air change rates in a bedroom of a single-family house. The distinct aspects of this study include longitudinal measurement over three years, natural ventilation substituted by hybrid ventilation halfway into the monitoring period, and unaltered building and user characteristics. The analysis is based on measurements of temperature, relative humidity, CO2 concentration, and window opening for three seven-month measurement periods from September 1 to March 31. The measurements are complemented by in-depth user feedback and an audit of the building structure and installed HVAC systems. A clear correlation was observed between the values of relative humidity and carbon dioxide concentration and the type of ventilation strategy. A significant influence of residents’ behavior on the achieved indoor air parameters was observed. Full article