Energy Consumption Simulation Research Articles

Factors Influencing Public Building Energy Consumption: A Case Study of Changjiang River Administration of Navigation Affairs in China

Based on the energy consumption data of the Changjiang River Administration of Navigation Affairs public building located in Wuhan, China, this paper analyzes the energy consumption characteristics of public buildings. Using the DesignBuilder energy simulation software (v7.0.0.096), various factors influencing building energy consumption are investigated. Furthermore, SPSS (v26.0.0.0) is employed to conduct correlation analyses between measured and simulated energy consumption data. The results indicate that the most significant factors affecting energy consumption are outdoor temperature, office equipment usage time, anticipated room temperature settings, boiler usage time, and per capita daily water consumption. By exploring the factors influencing energy consumption in public buildings, this study contributes novel insights into setting targets, adjusting schemes, and achieving energy-saving effects.

Analysis of Energy Consumption and Economy of Regional Gas Tri-Supply Composite System

With the development of Chinese society, there is an increasing demand for emissions reduction and the stable operation of the power grid. Regional comprehensive energy supply systems have entered the public’s view owing to their advantages of reducing capacity, unified dispatch, improving efficiency, and reducing energy consumption. This paper focuses on a system under construction in Chongqing, which adopts a combined gas tri-supply (combined cooling, heat, and power, CCHP) and dynamic ice storage cooling system as the research object. By establishing a mathematical model for the simulation research, this study examines the start–stop priority sequence of the gas tri-supply subsystem and the heat pump subsystem under the ice storage priority strategy in winter and summer and proposes corresponding optimization solutions. By comparing the annual operating energy consumption of the system, we conclude that the gas tri-supply composite system has good economic efficiency and peak-shaving capability, indicating that regional gas tri-supply composite systems have great application potential in the future. The proposed optimized operation strategy and simulated energy consumption calculation provide theoretical guidance for the construction and operation of both this project and similar projects.

Research on the Energy Consumption Influence Mechanism and Prediction for the Early Design Stage of University Public Teaching Buildings in Beijing

The public teaching buildings of universities have a large flow of people, high lighting requirements, and large energy consumption, which present significant potential for energy saving. The greatest opportunity for integrating “green” architectural design strategies lies in the design phase, especially the early stage of architectural design. However, current designers often rely on experience or qualitative judgment for decision-making. Thus, there is a pressing need for rational and quantitative green architectural design theories and techniques to guide and support decision-making for the design parameters of teaching buildings. This study, based on field surveys of 40 teaching buildings, constructs building archetypes regarding energy consumption including 28 typical values. Based on the “Rectangle”, “L”, “U”, and “Courtyard” archetypes, through batch energy consumption simulation and multiple regression methods, the influence mechanisms of nine energy consumption influencing factors on four types of building energy consumptions were explored, and energy consumption prediction models were derived. The findings of this research can serve as factor evaluation and selection in the early stage of architectural design for public teaching buildings at universities, and the prediction model can assist in the early estimation of energy consumption. This aims to enrich and supplement green architectural design methods by supporting the design of green public teaching buildings and providing reference and application for relevant engineering practices.

Two processes based on a data-driven model combined with dynamic simulation for demand forecasting and providing energy saving measures

In this study, two processes of predictive model combining dynamic simulation and regression model were presented. First, (1) the demand forecasting process defined in this study is a method of predicting energy consumption based on the simulated energy consumption of a target building, and (2) the energy saving process is a method of setting an energy reduction target based on the predicted energy consumption and providing energy saving measures to achieve the target. Specifically, there are two functions based on the regression models which are predicting actual energy consumption by inputting the energy consumption simulation data, and inversely inputting the actual energy consumption and deriving the corresponding simulation conditions. As a result of predicting building energy consumption through the demand forecasting process, the performance in the heating season showed CV-RMSE was 14.622%, and in the cooling season CV-RMSE was 5.877%. In addition, in the case study using the energy saving process, it was possible to derive the heating and cooling set temperature for 5% energy saving as an energy saving method by using weather forecast data.

Energy performance of buildings with multi-ribbed composite wall structural system

Multifunctional multi-ribbed composite wall (MRCW) structural system has been increasingly used due to its dual load bearing and energy saving capacities. Most of existing studies were focused on its mechanical properties. This paper aims to evaluate its energy saving effect. To this end, two models are constructed using EnergyPlus for the same residential building in Beijing, China, but with different systems of MRCW and shear wall. The dynamic simulation of hourly energy consumption throughout one year is carried out at the building operation stage. The results show that the heating energy consumption is higher than the cooling energy consumption. The total energy consumption of the MRCW system can be reduced by 11.4% compared with that of the shear wall system. Further, the annual energy consumption of the residential building models in five typical climate regions in China with different orientations is simulated. The results show that the energy saving of MRCW system range from 5% to 13% in the five regions when compared with shear wall system, and the absolute value of energy saving is the largest in severe cold and cold regions. The north-south orientation is the best energy-saving orientation. Based on this study, it can be concluded that, other than carrying load, MRCW system can also save energy compared with shear wall system, especially in severe cold and cold regions.

Machine Learning-Based Simulation of the Air Conditioner Operating Time in Concrete Structures with Bayesian Thresholding.

Efficient energy use is crucial for achieving carbon neutrality and reduction. As part of these efforts, research is being carried out to apply a phase change material (PCM) to a concrete structure together with an aggregate. In this study, an energy consumption simulation was performed using data from concrete mock-up structures. To perform the simulation, the threshold investigation was performed through the Bayesian approach. Furthermore, the spiking part of the spiking neural network was modularized and integrated into a recurrent neural network (RNN) to find accurate energy consumption. From the training-test results of the trained neural network, it was possible to predict data with an R2 value of 0.95 or higher through data prediction with high accuracy for the RNN. In addition, the spiked parts were obtained; it was found that PCM-containing concrete could consume 32% less energy than normal concrete. This result suggests that the use of PCM can be a key to reducing the energy consumption of concrete structures. Furthermore, the approach of this study is considered to be easily applicable in energy-related institutions and the like for predicting energy consumption during the summer.

Research on Multi-Objective Optimization Design of University Student Center in China Based on Low Energy Consumption and Thermal Comfort

Ensuring optimal building performance is vital for enhancing student activity comfort and fostering energy-saving initiatives toward low-carbon objectives. This paper focuses on university student centers in China, aiming to diminish building energy consumption while enhancing indoor thermal comfort. Parametric modeling of typical cases is executed using the Grasshopper 1.0.0007 software package, and the simulation of building energy consumption and indoor thermal comfort relies on the Ladybug and Honeybee plug-in. Employing a multi-objective optimization design method and the Octopus multi-objective optimization algorithm, this study integrates numerical simulations and on-site surveys to analyze how factors like building form, orientation, envelope structure, and others impact the indoor and outdoor environment. A comprehensive optimization design approach is implemented for the building’s exterior components, including the walls, windows, roof, and shading system. After conducting a comparative analysis of the annual comprehensive energy consumption and indoor thermal comfort before and after the optimization plan, it is determined that implementing these measures reduces the annual comprehensive energy consumption of the building under study by 58.8% and extends the duration of indoor thermal comfort by 53.0%. This study presents a practical optimization design methodology for university student center architecture in China, aiding architects in decision making and advocating for energy-efficient building designs.

Moisture buffer value for hygroscopic materials with different thicknesses

Moisture buffer value (MBV) is a critical parameter for assessing hygroscopic material's ability to moderate indoor humidity variation. The original MBV theory is strictly valid only for a semi-infinite (or “very thick”) material. When the material is thinner than semi-infinite, the material's thickness will affect its moisture buffering ability. The existing MBV theory is inapplicable. This study proposed a new numerical method to calculate a material's MBV at different thicknesses. The proposed model is simple and efficient. The relation between a material's MBV and thickness and the optimal thickness can be obtained without extensive experimental measurement. What's more, the material's adsorption and desorption isotherms, as well as the material's hysteresis loop and scanning isotherms, are incorporated in the proposed model, making it applicable to advanced desiccant materials like Metal-Organic Frameworks (MOFs). MIL-100(Fe), one of the most promising MOF candidates for indoor humidity control, was used to validate the newly developed model. MBVs of MIL-100(Fe) samples with different thicknesses were measured, and the experimental data closely matched the simulated results. Finally, a building energy consumption simulation model was developed based on the proposed numerical model. A MOF panel with its optimal thickness was placed in the BESTEST typical office room located in Copenhagen. The results show that MOF can reduce about 30 % of the energy consumption of air conditioning in a purely passive way.

Research on Energy-saving Design for University Library Spaces in Cold Regions

With the popularization of open-shelf reading in university library, the change of use mode leads to the change of space mode, and gradually develops from corridor mode to large-scale and deep composite centralized space organization mode. However, the large and deep open reading space and atrium space in university libraries increasingly rely on artificial lighting, mechanical ventilation and mechanical temperature regulation to meet the comfort needs of space thermal environment. Moreover, the improper control of passive design strategy in the early stage further leads to the reduction of indoor thermal environment comfort and the increase of building energy consumption. In the early stage of architectural design, through reasonable passive space layout design, the use of air conditioning equipment can be greatly reduced, energy consumption can be reduced, and the goal of green development can be achieved. Through extensive collection and analysis of 23 university libraries built in cold climate region, by making a statistical study on the building type, building area, number of floors, building scale and building plane aspect ratio, summarizing and extracts the prototype. Referring to the typical cases in cold climate area, two core groups that reading spatial variable group and atrium spatial variable group are proposed by controlling a single variable, in which each group has four plane layout modes. The dynamic energy consumption simulation software DesignBuilder is used to simulate the annual cooling, heating and lighting load of each group in cold climate region, and the results are converted into energy consumption values for analysis. The final results show that among the four combination modes of reading spatial variable group, the overall energy consumption of compound type is the smallest, and the energy-saving rate is the highest, up to 3.71%. The overall energy consumption of parallel type and surround type is little difference, and the overall energy consumption of surround type is the highest. The energy-saving rate of the four groups of reading modes is as follows: compound type > decentralized type > parallel type > surround type. The total energy consumption of the atrium partial staggered floor group is lower than that of the non staggered floor group. Among the four combination modes of the atrium spatial variable group, the overall energy consumption of the organization form of the atrium partial staggered floor to the south is the smallest, the energy-saving rate is the highest, reaching 5.84%, and the energy-saving rate of the atrium partial staggered floor to the north is the lowest. Therefore, in the preliminary scheme design stage, low-performance spaces such as traffic auxiliary space can be placed at the building boundary to form a buffer zone similar to the transition space, so as to alleviate the negative impact of the external adverse climate environment on the internal space. At the same time, it can be considered to carry out partial staggered floor design of the atrium, and give priority to arranging the atrium on the south side, which is not only conducive to reducing the overall energy consumption of the building and achieving the energy-saving goal, but also enhance the diversification of vertical sections and promote the interest of the internal space of modern university libraries.

Benzoic acid catalyzed production of xylose and xylooligosaccharides from poplar

The proficient synthesis of xylose and xylooligosaccharides (XOS) from lignocellulosic biomass proved to be a formidable undertaking, particularly in the absence of preliminary hemicellulose isolation. In this study, the potential of benzoic acid (BZA), a non-toxic and edible acidic catalyst, was assessed for the pretreatment of poplar in order to produce xylose and xylooligosaccharides (XOS). At low temperatures (< 160°C) or low acid concentrations (< 2%), the main product obtained from the depolymerization of hemicellulose was XOS, and no significant depolymerization occurred on a large scale. The results showed that the highest extraction yield of hemicellulose was 93.1% with 2% BZA at 160°C for 0.75 h, hemicellulose was mainly converted into xylose and XOS, with xylose accounting for 27.1% and XOS accounting for 46.7%. Meanwhile, the results of the process simulation of industrial energy consumption indicated that the amount of water added was the main factor affecting energy consumption in industrialization, followed by temperature. This study presented a promising approach for the industrial-scale manufacturing of xylose and XOS from poplar as a primary resource.

Simulation of Energy Consumption of Radiant Refrigeration Coatings on Buildings

In recent years, radiation refrigeration materials have developed rapidly, and a lot of research has been carried out from simulation and experimental testing. In this paper, the radiation refrigeration coating is applied to a small residential container building in Chengdu area. The experimental results show that the radiation refrigeration coating can reduce the indoor temperature and improve the indoor thermal environment. Combined with the numerical simulation analysis, it is found that the radiation refrigeration coating is suitable for the roof of the building, which can reduce the energy consumption of 2.47 kWh/ m2 per unit area per year.

Semi-experimental investigation on the energy performance of photovoltaic double skin façade with different façade materials

The photovoltaic double skin façade (PV-DSF) is a cutting-edge building envelope renowned for its dynamic nature and power generation capabilities, which attracts substantial scientific attention. However, the current lack of experimental support makes it challenging to draw definitive conclusions about the influence of façade material. This study aims to address this gap by investigating the energy performance of PV-DSF with different façade materials, thereby establishing an empirical foundation for its optimization. In this regard, the full-size comparison experiments on PV-DSF with 20/40% photovoltaic (PV) glass as external façade and laminated/double glass as internal glass were conducted in Harbin, China. The EnergyPlus software is adopted for the simulation of lighting energy consumption. The results indicate that PV-DSF with 40% PV outperforms that with 20% PV, leading to significant reductions in total energy consumption in both summer (22.73%) and winter (16.84%). The double glass can prevent 0.49 MJ of total heat gain in summer, which is accompanied by a marginal 0.03 MJ increase in winter energy consumption. In total, for optimal annual performance, 40% PV and double glass are recommended as the façades of PV-DSF. The results of this investigation can provide an experimental foundation for PV-DSF optimization in sustainable building design.

Validating ‘GIS-UBEM’—A Residential Open Data-Driven Urban Building Energy Model

The study of energy consumption in buildings, particularly residential ones, brings with it significant socio-economic and environmental implications, as it accounts for approximately 40% of CO2 emissions, 18% in the case of residential buildings, in Europe. On a number of levels, energy consumption serves as a key parameter in urban sustainability indicators and energy plans. Access to data on energy consumption is crucial for energy planning, management, knowledge generation, and awareness. Urban Building Energy Models (UBEMs), which are emerging tools for simulating energy consumption at neighborhood scale, allow for more efficient intervention and energy rehabilitation planning. However, UBEM validation requires reliable reference data, which are often challenging to obtain at urban scale due to privacy concerns and data accessibility issues. Recent advances, such as automation and open data utilization, are proving promising in addressing these challenges. This study aims to provide a standardized UBEM validation process by presenting a case study that was carried out utilizing open data to develop bottom-up engineering models of residential energy demand at urban scale, with a resolution level of individual buildings, and a subsequent adjustment and validation using reference tools. This study confirms that the validated GIS-UBEM model heating and cooling demands and consumption fall within the confidence bands of ±15% and ±12.5%, i.e., the confidence bands required for the approval of official alternative simulation methods for energy certification. This paves the way for its application in urban-scale studies and practices with a well-established margin of confidence, covering a wide range of building typologies, construction models, and climates comparable to those considered in the validation process. The primary application of this model is to determine the starting point and subsequent evaluation of improvement scenarios at a district scale, examining issues such as massive energy rehabilitation interventions, energy planning, demand analysis, vulnerability studies, etc.

Preparation study and simulation of high transmittance W–Sn–Zr Co-doped VO2 thin films prepared by sol-gel method for energy-saving smart windows

The thermochromic properties of vanadium dioxide (VO2) hold great promise for applications in smart glass windows. VO2 films exhibit a high phase transition temperature (Tc), low visible transmission (Tlum), and low solar modulating ability (ΔTsol), making them inadequate for the requirements of smart glass windows. While some improvement in VO2 film performance can be achieved through single-element doping, these limited enhancements still fall short of ideal results. Therefore, there is a pressing need for the improvement of VO2 films. In this study, we utilized the sol-gel method to prepare VO2 samples simultaneously doped with three elements: W, Sn, and Zr. Microscopic characterization confirmed the successful incorporation of these elements. Optical measurements, including ultraviolet–visible–near-infrared spectroscopy, were conducted to assess the optical properties of the films. Ultimately, outstanding Tlum (69%) and ΔTsol (14%) were achieved, along with an appropriate Tc (27.6 °C). Energy consumption simulations were performed using the EnergyPlus model with experimental data, revealing that compared to conventional glass, VO2 glass reduces total cooling energy consumption by 9.8%. In comparison to previous work, the multi-element-doped films push the performance limits of VO2 films, offering a viable approach for fabricating superior VO2 smart glass windows.

Generation and application of typical meteorological year data for PV system potential assessment: A case study in China

The potential assessment of photovoltaic(PV) systems is of great significance for installing and laying out PV. Short-term meteorological data cannot reflect the local climate characteristics, so it is not suitable for the potential assessment of PV. A typical meteorological year(TMY) can reflect a region's climatic characteristics, and therefore, it is appropriate for the potential assessment of PV. Although the generation methods of TMY for building energy consumption simulation are mature, there are still limited studies on TMY for PV. Given this, this study employs a method to generate TMY data suitable for the Chinese region, while redefining the influencing factors and their respective weights. A TMY dataset was built for 90 cities based on 38 years of measured data in China and applied to BAPV potential assessment. The study assesses annual generation, CO2 reduction, levelized cost of electricity (LCOE), and net returns(NR). The results reveal the highest annual electricity generation in the Northwest region, with Shiquanhe, Golmud, and Ejina sites reaching 215.65 MWh, 201.2 MWh, and 197.5 MWh, respectively. Conversely, southern and coastal regions, notably Chongqing, exhibit the lowest generation at 75.75 MWh. BAPV in Class I tariff areas, along with some Class II and III areas, can achieve demand-side parity (DSP) in full on-grid mode. Through operational adjustments, DSP can be implemented in 23 currently ineligible areas. This study provides dataset support for calculating PV system power generation and analyzes PV potential across diverse cities. The results contribute to policy formulation and future solar energy research, facilitating precise calculations for efficient green power planning in pursuit of carbon neutrality.

A comprehensive investigation of zeolite/polyurea cooling coating on concrete for building energy conservation

Passive daytime radiative cooling (PDRC) materials are beneficial to energy conservation and emission reduction of buildings. Currently, the design of PDRC coatings for exterior walls and roofs of buildings places excessive emphasis on improving the solar reflectance (Rs) and infrared emissivity (Ei) of the coating, while neglecting other important properties of building coatings, such as adhesion, waterproofness, corrosion resistance, and weather resistance. To address these deficiencies, this work developed a (calcined zeolite)/polyurea (CZ/PU) PDRC coating with excellent comprehensive performance for building exterior walls and roofs, using CZ and PU as raw materials. The CZ/PU coating is prepared using a method that is completely consistent with existing paint production and construction techniques, and can be applied to large-area building surfaces at scale. The Rs of the CZ/PU coating is 97.4 %, and the Ei is 94.4 %. Under direct sunlight in summer, the CZ/PU coating achieved significant PDRC effects under both adiabatic conditions (using test equipment to reduce heat conduction and convection) and natural conditions. The corresponding radiative cooling temperatures are 14.9 °C and 4.4 °C, respectively. In addition, the CZ/PU coating also exhibits excellent water resistance, reducing the capillary water absorption rate of a cement block by 78 %. In addition, the adhesion strength of the CZ/PU coating to the substrate reached the highest rating (rating 0). In particular, the optical properties, radiative cooling function, water absorption, and adhesion force of the CZ/PU coating showed ultra high stability in ultraviolet aging experiments. Energy consumption simulations show that the average energy saving efficiency of the CZ/PU coating on the annual total building energy consumption of ten typical Chinese cities is as high as 13.3 %. The CZ/PU-based coating developed in this work comprehensively considers various issues that may be faced in the practical application of radiative cooling architectural exterior wall coatings, providing an experimental foundation for promoting the application of radiative cooling coatings in buildings.

Trade-Off Judgement for Daylighting and Energy Consumption in the High and Large Space of the University Gymnasium in Beijing

Taking the high and large space of the University of Science and Technology Beijing Gymnasium as this research object, this paper analyzes the influence of different window positions, window-to-wall ratio (WWR), solar heat gain coefficient (SHGC), heat transfer coefficient (K), and visible light transmittance (VT) on the total indoor energy consumption in winter and summer and obtains the relationship between the daylight factor and VT formed when the window is opened per unit area. Through energy consumption simulation, the variation law and calculation formula for indoor total energy consumption are obtained. The results show that the SHGC and K of the exterior window have a significant influence on the total energy consumption. By using the energy consumption simulation of different types of exterior windows, it is concluded that the SHGC of the south-facing window is negatively correlated with the variation of air conditioning energy consumption per unit area Δe1,w, while the others are positively correlated. Moreover, the SHGC and K of the skylight have the most significant influence on the Δe1,w. The total energy consumption decreases and then increases with the increase in the window area, and there is a lowest point, so the right side of the lowest point is less than or equal to 105% of the lowest total energy consumption as a reasonable window area zone. Finally, a progressive optimization method for weighing daylighting and energy consumption in university gymnasiums in Beijing is proposed.

Construction of robust silica-hybridized cellulose aerogels integrating passive radiative cooling and thermal insulation for year-round building energy saving

Passive radiative cooling (PRC) is a promising carbon reduction technology that radiates heat into the universe through atmospheric transparency window (ATW) to cool objects below ambient temperature with zero energy consumption. However, so far the cooling efficiencies of most PRC designs are inevitably restrained by inadequate optical properties and parasitic heat gains from ambient air. These defects are overcome by developing aerogel coolers with functional integration of low absorption of solar irradiance, strong mid-infrared emittance, and high thermal insulation in one design. In particular, cross-linked silica-hybridized cellulose acetate is exploited to construct robust aerogels with well-arranged nano/micro porous structures, representing a solar reflectance up to ∼96 % and an ATW emissivity of ∼97 %. Such aerogels can realize a subambient temperature drop of ∼9.15 °C during the daytime and maintain their remarkable cooling performance even in cloudy, moist, and windy climates. The aerogel coolers also show excellent anti-aging, self-cleaning, and compression resistance, making them adaptable for long-term cooling applications. The year-round energy consumption simulations demonstrate that an average total energy saving of 13.87 kW m−2 per year can be promisingly achieved in China when the aerogel coolers are integrated on building roofs. This work paves a new way to manufacture more cost-effective and sustainable cooling materials for efficient building energy conservation in the future.

Simulation of fishery energy consumption and carbon emissions in Zhoushan City based on the long-range energy alternatives planning system model

To understand the current situation and development trend of energy consumption and carbon emissions in the fishery industry, a Long-Range Energy Alternatives Planning System (LEAP)-fishery model for Zhoushan City was constructed, and the trends of energy consumption and carbon emissions in the Zhoushan City fishery industry were analyzed under the business-as-usual scenario, the low-carbon scenario, and the strengthened low-carbon scenario. The results show that under the business-as-usual scenario, the future energy consumption of Zhoushan City’s fisheries in general shows an increasing trend, and the composition of energy consumption in all scenarios is primarily dominated by fossil energy, with diesel and coal predominating. In terms of the structure of end-use energy consumption, fishing vessels and aquaculture consume the most energy, with energy consumption exceeding 30% of total energy consumption in all scenarios. In terms of the emission reduction contribution rate, which the promotion of clean energy generation, the improvement of energy efficiency, and the reduction of aquaculture production play key roles in the low-carbon development of the fishery industry. From an economic perspective, carbon reduction measures such as reduction of aquaculture production and increased efficiency of energy delivery would have significant economic benefits, but these measures have limitations. Finally, suggestions are made to optimize the energy structure, improve the implementation of energy intensity and total energy control, and strengthen public awareness of energy conservation to reduce carbon emissions from the fishery industry, thus making the research in this paper relevant to real-world situations.

Simulation of rural residential energy consumption in different climate zones based on Dest-H

Simulation of rural residential energy consumption in different climate zones based on Dest-H