•This paper investigated the energy impact of DSF design regarding window glazing type and cavity depth.•Parametric and optimization studies were conducted based on a validated DSF model.•Energy ...consumption decreased when the cavity depth of the DSF decreased.•Results show the significance of the initial DSF design on the thermal load of the adjacent conditioned zones.
The thermal characteristics of a cavity in a double skin facade (DSF) may vary according to the design of the DSF, since the DSF layers are generally fully glazed. Such thermal characteristics of the cavity influence the thermal load in adjacent air conditioned zones. Thus, the purpose of this study is to quantitatively analyze the impact of the initial DSF design, regarding window glazing type and cavity depth, on the energy consumption of adjacent conditioned zones. To this end, parametric and optimization studies on the DSF design were conducted based on a validation model. In the parametric study, the largest variation of energy consumption was the case when the window glazing type on the outside surface of the inner layer changes. Also, energy consumption decreased when the cavity depth of the DSF decreased. Finally, the model in which the optimal DSF design is applied resulted in a 5.62% reduction in energy consumption. These results suggest the significance of the initial DSF design on the thermal load of the adjacent conditioned zones.
Concerns related to food security and animal welfare have led to increasing interest in analyzing the energy demands of heating, ventilation, and air conditioning (HVAC) systems in livestock ...buildings. However, building energy simulation (BES) model, which facilitates precise HVAC systems energy analysis, is difficult to use for non-experts, and particularly, its usability drops significantly in livestock buildings, which are often constructed without involvement of building engineers. This study, therefore, developed a tool that can analyze the energy demand of pigsties by changing geometric design variables with only several numerical inputs without separate 3D modeling. Pigsty geometric design types were classified by examining pigsty architectural design manual and web portal map search. A simplified tool, utilizing EnergyPlus and MATLAB graphical user interface, was developed to analyze energy demand in pigsties by leveraging simple user inputs for geometric design modeling. This tool simplifies exploring potential energy savings through geometric design changes in the early design stages of livestock buildings. The methodology introduced in this study lays the groundwork for future enhancements, including the integration of various design-phase variables beyond geometric design.
•Simplified tool development for pigsty energy demand analysis, simulated by minimal numerical input requirements.•Generalized pigsty geometric design classification to simplified building energy simulation tool development.•Parameterization for coordinate definition from type-specific geometric features, facilitated by simple numerical inputs.•Leveraging EnergyPlus and graphical user interface for user-friendly assessment of geometric design-related energy savings.
Livestock facilities commonly generate NH3, a hazardous substance that may also harm livestock. Therefore, monitoring of NH3 concentrations in livestock facilities is necessary to ensure proper ...control. However, NH3 is alkaline and toxic, causing corrosion inside detection sensors and making monitoring difficult. This study proposes a virtual sensor concept to complement the durability of NH3 physical sensors. The study also conducts a long-term performance validation of a data-driven NH3 concentration prediction model. Results indicate that the model's prediction performance declines sharply when the data generation pattern inside the livestock facility changes due to changes in outdoor conditions and facility operation. Furthermore, the prediction performance of the model differed depending on the training data period settings when updating the model. Hence, the model needs versioning and update management to respond to the data generation pattern in the livestock facility when operating the NH3 concentration virtual sensor. The virtual sensor is expected to enhance monitoring and reduce sensor management costs in livestock facilities.
In response to the need to improve energy-saving processes in older buildings, especially residential ones, this paper describes the potential of a novel method of disaggregating loads in light of ...the load patterns of household appliances determined in residential buildings. Experiments were designed to be applicable to general residential buildings and four types of commonly used appliances were selected to verify the method. The method assumes that loads are disaggregated and measured by a single primary meter. Following the metering of household appliances and an analysis of the usage patterns of each type, values of electric current were entered into a Hidden Markov Model (HMM) to formulate predictions. Thereafter, the HMM repeatedly performed to output the predicted data close to the measured data, while errors between predicted and the measured data were evaluated to determine whether they met tolerance. When the method was examined for 4 days, matching rates in accordance with the load disaggregation outcomes of the household appliances (i.e., laptop, refrigerator, TV, and microwave) were 0.994, 0.992, 0.982, and 0.988, respectively. The proposed method can provide insights into how and where within such buildings energy is consumed. As a result, effective and systematic energy saving measures can be derived even in buildings in which monitoring sensors and measurement equipment are not installed.
South Korea has potential in developing large-scale pig-farming practices. However, poorly designed facilities and ventilation structures lead to production losses and energy inefficiency. This study ...examines energy efficiency in pig houses by establishing a heating, ventilation, and air-conditioning (HVAC) system. Using the current ventilation system of the baseline energy model, case studies were conducted. Compared with baseline case 1, energy consumption of remaining cases were lower. This suggests that the pig house is currently energy inefficient. Photovoltaic (PV) generation, contributing toward 35% of the annual energy consumption, for a sustainable pig house was investigated. This energy model shows energy efficiency potential. Therefore, expanding research into energy management is essential for optimal facility design and operation using the energy model.
•Sustainability of a pig house was analyzed using energy model.•Efficient and improved system saved approximately 33.8% more energy.•Annual PV generation was equal to 35% of the pig house's annual energy consumption.•The study aims to expand research to energy management using design and scenario.
This paper proposes a flexible modeling approach to develop a theoretical reference building (RB) for energy analysis. We designed an RB for five non-residential buildings, using dynamic simulation ...from statistically analyzed data of building stock in South Korea. For modeling, four subsets of data—form, envelope, system, and operation—were assessed. This study uses the autosizing function within EnergyPlus, to develop the RB. The proposed approach allows for a flexible design where capacities and flow rates of the heating, ventilation, and air-conditioning (HVAC) system match the newly defined RB model. This approach would be ideal for closing the gap between the architectural data and equipment elements. The RB developed in this study allows for performing energy performance analysis by end-use. The analysis results by the end-use can provide support for country-level greenhouse gas (GHG)-mitigation-strategy development.
Multiple sensor nodes are preferred for the development of digital twins in indoor environments; however, it poses significant financial burdens. Therefore, considering both cost-effectiveness and ...information richness, optimal physical sensor placement and efficient virtual sensor operation must be balanced. Data-driven techniques for sensor placement prioritize locations via statistical metrics, information fidelity, and signal strength. When extending spatial sensing through virtual sensors, the indirectly determined physical sensor sites encounter challenges like multicollinearity and overfitting, hampering the reliability of predictive models (virtual sensors). To address this, this study introduces an algorithm that selects optimal physical sensor combinations based exclusively on virtual sensor performance. The results highlight the superiority of our proposed algorithm over conventional methods for virtual sensor development. Notably, our approach reduces computational workload compared to brute-force methods. This algorithm provides an economical means to manage extensive data and holds substantial promise for advancing digital twin capabilities in indoor environments.
•Algorithm to optimize physical sensor placement for virtual sensor performance.•Error rates below 2% obtained in various test scenarios.•Outperformed other data-driven methodologies in virtual sensor performance.•An economical solution for effective digital twin development in indoor environments.
Energy scarcity and environmental damage necessitates efficient design, which requires significant information from different sources. As decisions affecting energy performance are made at early ...stages based on minimal information, support tools for the energy-efficient design of buildings are necessary during this period. Energy efficiency is a critical initial planning stage factor when designing smart farms. This study developed early design tool using building performance simulation (BPS) model for indoor fish farms which was validated with on-site measurement data for 120 days. The average MBE and the Cv(RMSE) values of the BPS model satisfied the error rate within the hourly criteria ranges for the entire measurement period. Design parameters for an early design tool were determined through a Morris sensitivity analysis. An early design tool was developed using the MATLAB graphical user interface, facilitating the search for variables that increased energy efficiency and enabling energy consumption comparisons of different alternatives.
•Propose a method for utilizing building performance simulation in aquaculture building.•Validated the simulation results by comparison with on-site measurement data.•Selected early-stage design parameters for indoor fish farm using Morris sensitivity analysis.•Development of design tools for critical decisions from the early design stage.•Tool can be used to evaluate parametric and alternative designs suitable for the indoor fish farm.
In general, for livestock building, a simple system for controlling the HVAC system that is based only on the indoor air temperature is applied. This study evaluated the applicability of temperature ...humidity index (THI)-based ventilation systems installed in livestock buildings using a building energy simulation model. Based on the monitoring data of an actual pig house, the integrated predictive performance of the indoor temperature and humidity of the building energy simulation model was calibrated. Additionally, the indoor environment of the existing temperature-based control and THI-controlled ventilation systems was compared through simulations. The average THI and the section exceeding the THI threshold were both lower compared to the existing system. This was because the part load ratio of the fans of the THI-controlled ventilation system was higher than that of the existing system, indicating better ventilation. These results suggest that THI-based ventilation systems can overcome the limitations of existing temperature-based systems and effectively improve the thermal stress management of livestock buildings. This study portrays that the indoor environment can be improved by simply changing control variables, while presenting the field applicability and research value of THI-based control systems in the management of livestock environments.
Semi-transparent photovoltaic (STPV) modules are a renewable energy source that significantly affects the energy load of buildings by simultaneously producing power and acting as a window. Therefore, ...the application of STPV to buildings requires investigation from various perspectives.
In this study, the space with STPV was modeled using EnergyPlus and the simulation results were compared with the mock-up data. The characteristics of power production according to cell type were not reflected in simulation because only the cell efficiency was applied to calculate in simulation unlike data obtained from a mock-up. Moreover, the result of analyzing the data based on the mock-up indicated that the indoor temperature in the space with the c-Si module was higher than that in the space with the a-Si. However, the opposite result was derived from simulation. This result was obtained because a temperature increase of modules during power generation was not reflected in simulation. Furthermore, it was found that the indoor temperature was analyzed based on only the u-value and SHGC in simulation because the indoor temperature increasing by the radiation from the STPV was not reflected in simulation. This study proposes the necessity and direction of algorithm improvement through comparison between simulation and mock-up.
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