Energy-saving Efficiency Research Articles

A New Electrohydraulic Hybrid Energy-Saving System Used on the Reversible Rolling Mills

In the face of the global energy crisis, the use of hybrid technology is an important way to achieve efficient energy storage and utilization. Hybrid systems have been successfully applied to automobiles and construction machinery, but no research study has been conducted on the design and application of energy recovery systems for reversible rolling mills. This article proposes a new type of noncoaxial parallel electrohydraulic hybrid drive system configuration for reversible rolling mills to save energy. It is proposed to collect the braking energy of the previous pass of the reversible rolling mill roll and the surplus power of the original primary drive motor and then start or accelerate the process for the next roll pass. A test experiment was established and the energy-saving efficiency of the proposed system was verified. By rolling 14 passes, 255.892 kJ of energy can be recovered. The overall energy efficiency rate is around 71.547%. The system will significantly promote energy saving, low carbon, green, and other aspects of the reversible rolling mills.

Study on optimization of thermal property parameters of phase change wallboard and its application simulation in the building

In this paper, a parameter-based design approach for phase change wallboard is presented. Based on existing gypsum composite phase change materials, COMSOL simulation software was used to understand the influence of parameters including phase change temperature, wallboard thickness, thermal conductivity, and latent heat value on the thermal performance of phase change wallboard and analyze different indoor environments and energy-saving efficiency of various parameter schemes in practical application. The effect of those parameters for phase change wallboard that used in outer envelopes and inner partitions is also compared to determine an optimized scheme for phase change wallboard applied in the city of Xi'an. The results demonstrate the most important element that affects the inner surface temperature is the thickness of the phase change wallboard, then the phase change temperature, and last thermal conductivity. Using integrated PCM on the envelope is not only beneficial to adjust the indoor thermal environment and reduce energy consumption, but also help to achieve the best cooling and energy conservation effects by optimizing material parameters in practice. The phase transition temperature of PCM applied in walls should approach mean temperature. Furthermore, exterior walls need PCW with larger thickness and smaller thermal conductivity, and interior walls equip PCW with higher thermal conductivity and latent heat. The optimized scheme can reduce the average room maximum temperature by 1.24 °C and the cooling load by 953 W per square meter.

Contract decisions analysis of shared savings energy performance contracting based on Stackelberg game theory

Energy Performance Contracting is a contractual arrangement between energy users and Energy Service Companies (ESCOs) and is currently the main mechanism for implementing energy-saving retrofitting measures in existing buildings. The paper centers around the decision-making conundrum pertaining to the energy-saving sharing percentage and initial project investment within the realm of shared savings Energy Performance Contracting. By formulating a Stackelberg game-based decision-making game model, we examine the optimal contract decisions of both the energy user and the ESCO. The results of numerical experiments demonstrate that this method yields significant advantages for both energy users and ESCOs. Additionally, we observed that the employment of more sophisticated energy-saving technologies by the ESCO and a higher share of investment by the energy users result in superior energy-saving efficiency.

Connectivity Enhancement of E-VANET Based on QL-mRSU Self-Learning Energy-Saving Algorithm

With the development of smart cities and smart electric vehicles (EVs), the problem of improving the performance of Vehicular Ad-hoc Networks (VANETs) is gradually being emphasized. To improve the network performance of VANETs, some scholars have considered parked vehicles as roadside units, but have not paid attention to the energy consumption characteristics of vehicles, especially electric vehicles. Therefore, in this paper, we propose a QL-mRSU series artificial intelligence energy saving method to optimize the energy consumption of parked electric vehicles during communication. The method is based on electric vehicle self-organizing networks (E-VANETs), which dynamically cluster electric vehicles parked in parking lots by parameters such as traffic flow, number of service demands, and charging index in reinforcement learning, select the most suitable vehicles as mobile roadside units (mRSUs), and adjust the working mode according to environmental changes such as the number of service demands to achieve the effects of self-learning and energy saving. The simulation experimental results show that compared with other energy-based routing algorithms, the method is able to make optimal choices through self-learning with guaranteed communication quality and is more adaptable to traffic flow changes on the road, thus ensuring the stability of energy-saving efficiency. In addition, the method significantly improves the energy structure of electric vehicle parking clusters.

Effects of various connectors on the whole-life-cycle energy consumption of sandwich wall panels in five thermal zones of China

Connectors are not only an important mechanical component of sandwich wall panels (SWPs), but they also contribute to SWP energy loss because they penetrate thermal insulation layers. Reducing the energy consumption (EC) generated by connectors is critical for improving the energy-saving efficiency of SWPs throughout their life cycle. The mechanical and thermal parameters of connectors, structural layers, and insulation layers all have a coupling effect on the EC of connectors in the SWPs studied in this study. First, a connector diameter calculation model and a three-dimensional finite element (3-DFE) model were developed to investigate the mechanism of various connectors' effects on the thermal performance (TP) of SWPs with different structural and insulation layers. Due to the high shear strength of steel, the diameter of the steel connector was found to be 59% smaller than that of the FRP connector, and the thermal bridge effect of the steel connector is reduced by 78% at most when the coupling effect is considered. Then, based on TP, a life cycle cost assessment (LCCA) model was developed. Using five thermal zones in China as research subjects, it was discovered that the effects of connectors on the whole-life-cycle EC of SWPs depend on the value of degree days (DD). Steel connectors can reduce the total energy consumption cost of SWPs by up to 13.7% in Guangzhou when compared to GFRP connectors. The connector manufacturing EC dominated the whole-life-cycle EC in an area with a low DD value. Reduced thermal conductivities of structural layers could significantly improve the effects of connectors on the whole-life-cycle EC of SWPs in an area with a high DD value. These findings are critical for the development of effective SWPs.

Simulation Study on Variable Pressure Margin Energy Recovery of Electric Loader Actuator

The conventional electric loader uses a motor instead of an engine, which aligns with the current energy-saving and emission-reduction trend. However, the motor’s speed control performance and overload capacity are under-utilized, and the actuator suffers from the potential energy waste problem of the boom arm. This study proposes a variable pressure margin energy recovery system for the electric loader actuator. It uses a combination of a permanent magnet synchronous motor (PMSM) and a quantitative pump. It can achieve variable pressure margin control and energy recovery through the pressure feedback closed-loop control. AMESim is used to build the simulation model based on the system control strategy, actuator, supercapacitor, and PMSM mathematical mode. Under typical working conditions, the simulation study is conducted on a 50-type wheel loader to obtain cylinder displacement, system energy recovery, and energy-saving performance. The simulation results show that the system is feasible and can effectively reduce energy consumption. Its energy recovery efficiency is 65.4%. The PMSM energy supply is reduced by 28.6% with the variable pressure margin control. It has high energy-saving performance, and the energy-saving efficiency is 38.5%. It provides a reference for research on energy-saving systems for electric construction machinery.

Low‐Cost and Large‐Scale Producible Biomimetic Radiative Cooling Glass with Multiband Radiative Regulation Performance (Advanced Optical Materials 23/2022)

In article number 2202031, Xinping Zhang, Fuqiang Wang, and co-workers propose and achieve a low-cost and large-scale producible radiative cooling glass with multiband radiative regulation performance. Utilizing only three layers of thin films, the proposed glass can transmit visible light, block near-infrared light, and emit heat to outer space. Furthermore, it achieves a maximum temperature reduction of 18.1 °C in a rooftop measurement and a maximum energy-saving efficiency of 23.4% compared with common glass. This study provides a remarkable idea for designing high-performance energy-saving materials.

Research on Parameter Matching of the Asymmetric Pump Potential Energy Recovery System Based on Multi-Core Parallel Optimization Method

Aiming at the parameters of the different displacements and related components of the variable-displacement asymmetric axial piston pump (VAPP) required by the energy-recovery system of excavator booms of different tonnages, a rapid multi-process parallel optimization method of complex hydraulic products based on a multi-core CPU was proposed for parameter matching. The parameter matching was used to reasonably select relevant parameters so that the excavator’s boom energy-recovery and utilization system can improve operational efficiency and energy-saving efficiency under the premise of satisfying the normal working conditions of the working mechanism, and achieving the purpose of serializing VAPP products. A multi-objective optimization model was put forward according to energy-saving efficiency and operational efficiency. First, the accuracy of the acceleration method of the CVODE, a solver for stiff and non-stiff ordinary differential equation (ODE) systems, was verified by a physical prototype test. The results showed that the test and simulation results were in good agreement. A particle swarm optimization algorithm (PSO) was used to optimize the main parameters of the boom energy-recovery system to obtain the appropriate energy-saving efficiency and obtain the VAPP displacement and related component parameters required by the energy-recovery system of excavator booms of different tonnages. The simulation results showed that a motor working condition was necessary in the guaranteed descending stage, and the process of lifting–descending–lifting was completed under the condition that the total time did not exceed a certain value. The energy-saving rates of the 7-ton (7T), 12-ton (12T), 20-ton (20T), and 30-ton (30T) excavator boom energy-recovery systems reached 29.8%, 35.3%, 31.25%, and 27.88%, respectively. In the eight-core CPU workstation under the simulation conditions, compared with the Simulation X platform simulation method, the simulation efficiency of the multi-core CPU parallel method was improved by more than 80 times.

Parameter optimization of energy-efficient antenna system using period-based memetic algorithm

Antenna systems play a key role both in today's 5G or future 6G communication networks because they can convert electrical energy directly into electromagnetic waves. However, due to the imprecise antenna models, electrical energy loss is inevitable and enormous in the whole network. Therefore, the energy efficiency optimization of antenna models becomes extremely urgent by accurately estimating their parameters. In this paper, to reduce the energy loss in transmission, a novel period-based memetic algorithm (MA) framework is developed to improve the energy-saving efficiency of antenna models. A popular neighborhood field search (NFS) and a state-of-the-art differential evolution (DE), as a local optimizer and a global optimizer, respectively, are embedded into the MA framework for an instantiation, referred to as MDE-NFS. In the proposed MDE-NFS algorithm, a periodic switching-based scheme is studied to strike a balance between global exploration and local exploitation. To verify the performance of MDE-NFS, it is applied to parameter optimization of two different antenna models, including the microstrip antenna model and the Yagi–Uda antenna model. Moreover, MDE-NFS is also specifically compared with other algorithms on several numerical test sets. The comprehensively experimental results demonstrate that the MDE-NFS is promising to be a candidate parameter optimization approach to design energy-efficient antenna models.

Thermal analysis of hybrid photovoltaic-thermal water collector modified with latent heat thermal energy storage and two side serpentine absorber design

The most popular renewable energy source is solar energy, which characterises as free, clean, and environmentally friendly. Photovoltaics (PV) generate electricity from daylight, becoming increasingly popular in residential and other applications. The potential energy delivery from a photovoltaic module is a function of solar radiation falling on the front surface and module operating temperature. However, these systems are modified to improve energy generation by placing an absorber on the bottom side of the module termed a Photovoltaic Thermal (PVT) system to reduce module temperature. The current study aims to investigate the experimental heat transfer efficiency for the fabricated PVT system employing two-sided serpentine flow thermal absorber and phase change material (PCM). PCM discharge the latent heat during off-sunshine hours to provide additional hot water. The experiment setup was tested with water as a working fluid in the flow rate range of 0.0085–0.067 kg/s. The optimal flow rate at which maximum heat gain of 757 W was obtained 0.033 kg/s with an average energy-saving efficiency of 69 %. The results confirm enhanced energy delivery of 3–5 % by PVT-PCM system compared to reference PV module for the same ambient operating conditions. Furthermore, the study reveals that overall efficiency of the PVT setup augment with the use of a thermal absorber and PCM, while the thermal efficiency is a factor that depends on the working fluid properties.

Comparison study on two LT-PV/T systems with different tubular condensers

The concentric double-tube heat exchanger (CDTHE) proposed in our previous work addresses the limitations of the combined application of conventional loop thermosyphon photovoltaic/thermal (LT-PV/T) systems. Based on this, a novel non-concentric multi-tube heat exchanger (NMTHE) as the condenser of the LT-PV/T system was proposed in this paper, which improves the performance of system by reducing the flow resistance of the working fluid. Experimental platform was built to explore the performance difference between CDTHE-LT-PV/T and NMTHE-LT-PV/T system. Experimental results show that compared with the CDTHE-LT-PV/T system, the thermal efficiency, the electrical efficiency, the primary energy-saving efficiency and the exergy efficiency of NMTHE-LT-PV/T system relatively increase by 17.76%, 2.1%, 10.05% and 3.64%. Mathematical models for two systems are established and verified. Then the performance of the two systems under different solar radiation and ambient temperature is explored. Besides, the all-day performance of the two systems on typical winter days in four cities at different latitudes is predicted. The results show that the NMTHE-LT-PV/T has more prominent advantages in northern China at higher latitude. Furthermore, the influences of some structural parameters and operating setup on the performance of NMTHE-LT-PV/T system are discussed.

Energy-Saving Metro Train Timetable Optimization Method Based on a Dynamic Passenger Flow Distribution

The operation of metro trains with a focus on energy savings can effectively reduce operating costs and carbon emissions. Reducing traction energy consumption and increasing the utilization efficiency of regenerative braking energy are two important energy-saving approaches that are closely related to the metro train interstation running strategy and timetable. Changes in train mass caused by dynamic changes in passenger flow represent one of the important factors affecting the energy consumption and energy-saving operation of metro trains. In this study, the differences in the temporal and spatial distributions of metro line passenger flow were specifically considered, and an energy-saving metro train timetable optimization method focused on the dissipative regenerative braking energy utilization mode was studied. First, a logistic function is used to fit the passenger flow pattern of the origin-destination (OD) station pairs, and the number of passengers getting on and off at each station is derived by establishing the OD dynamic demand matrix for the entire metro line. Then, the passenger load in each station segment is calculated. Next, a timetable optimization model is established to minimize the net energy consumption based on the load difference between station segments and the train motion equation. The interstation running time and dwell time of the metro train are optimized to increase the amount of regenerative braking energy used during the overlap time between the traction and braking actions of adjacent trains in the train operation timetable. A particle swarm optimization and genetic algorithm (PSO-GA) structure is designed to solve the model. The PSO-GA structure has PSO as the main body and integrates the chromosome crossover and mutation operations of the GA into the iterative process to improve the search efficiency of the algorithm. Finally, the proposed method and model are tested based on the actual data of a metro line in Qingdao, China. The goodness of fit of the passenger flow pattern is 0.997. The energy consumption during the study period is reduced by 5169.67 kW h using the optimized timetable. The energy-saving efficiency decreases by 12.18% at a constant OD ratio during the entire travel time and by 20.23% at the same constant load for all station segments. The results of the case analysis prove the effectiveness of the proposed method and model. In addition, the energy-saving timetable can be better optimized by considering the differences in temporal and spatial distributions of dynamic passenger flow.

Environmental regulation, low-carbon technology progress and energy efficiency

Low-carbon technological progress is an important way to achieve energy conservation and emission reduction, as well as achieve the goal of peaking carbon emission and carbon neutrality. Due to the difference in energy input structure, the difficulty of attaining low-carbon technology progress in industries with different energy consumption levels will lead to different responses to environmental regulation, affecting energy efficiency. This paper demonstrates the theoretical mechanism of how environmental regulation affects energy-saving efficiency through low-carbon technological progress in industries with different energy consumption levels. By reconstructing energy consumption of different industries in each province, this paper estimates the low-carbon technology progress in high-energy-consuming industries and low-energy-consuming industries in 30 provinces and cities of China from 2000 to 2016. It carries out empirical tests using mediating effect model. The results show that nationwide, the impact of environmental regulation on energy efficiency through low-carbon technology progress is U-shaped. Low-carbon technology progress accelerates the inflection point, indicating that the progress of low-carbon technology is beneficial for strict environmental regulation policies to improve energy efficiency. It shows there is asymmetric regional heterogeneity in the impact of environmental regulation on energy efficiency through low-carbon technology progress in high-energy-consuming and low-energy-consuming industries: in the central-western region, the progress of low-carbon technology in high-energy-consuming industries is faster than that in low-energy-consuming industries; in eastern region, room for energy-saving through low-carbon technology in low-energy-consuming industries is more significant than that in high-energy-consuming industries. This paper provides empirical evidence and policy suggestions for China to implement differentiated environmental regulation policies in accordance with local conditions, promote green technology transformation, and conserve the ecological civilization.

Active solar collector located on roof ridge assisted Chinese solar greenhouse for thermal environment enhancement

ABSTRACT Maximizing the use of solar energy to increase the indoor temperature of greenhouse is of great significance to the green and energy-saving intensive greenhouse production in China. In this study, an active solar heating system (ASHS) was developed and analyzed, consisting of five solar water heaters equipped with vacuum tube solar collectors, one heat storage tank and heating system including booster pump and heating pipes. During the day, the water was heated in the solar collectors and stored in tanks before being placed into circulation in the heating pipes to distribute the heat to the aerial and root zones of plants. To evaluate the performance of ASHS and the feasibility of practical application, climate and plant growth parameters were monitored in two Chinese Solar Greenhouses (CSGs) located in Yangling, China. Results revealed that under the operating condition with the flow rate of 5.4 L/min, the effective heat collection, average heat collection efficiency and energy-saving efficiency of ASHS were 1.9 MJ/(m2•h), 64% and 84%, respectively. The coefficient of performance (COP) was between 4.5 and 6.2, and the payback period was 12.0 years. Furthermore, the results revealed that the ASHS successfully provided 76% of its annual heating needs, heated the CSG for 4 months and maintained the nocturnal temperature above 8 ℃. The actual application effect proved that it increased average indoor air temperature by 2.2 ℃ and substrate temperature by 3.3 ℃ in heated greenhouse. The growth rate of tomato plant height in the heated greenhouse was 0.7427 cm/d, greater than that in the unheated greenhouse (0.6 cm/d). The novel system proposed in this study adopting particular location enables the rise of the ambient and the substrate temperatures with lower energy consumption, improvement of the environmental conditions in CSG, and a more suitable growing environment for plants in the cold season.

A hybrid photovoltaic and water/air based thermal(PVT) solar energy collector with integrated PCM for building application

Based on the different requirements of solar energy integrated with buildings, a hybrid photovoltaic and thermal solar energy collector with integrated phase change material (PVT-PCM) have been developed. The thermal system combines air-based and water-based conditions to meet the building heat demand in different seasons. In addition, PCM is used to absorb the heat that was not taken away by the thermal system. And the vessel is optimized to enhance its thermal conductivity. The results of cross-season test show that the overall efficiency of the system is 39.4%, and the energy-saving efficiency is 64.2%. The system controls the temperature and utilizes the heat through the thermal system. The economic analysis and energy saving potential of the system in low latitude areas are analyzed. The results show that the additional payback period of the system is 13.1 years. And based on the local energy structure, the maximum CO2 emission can be reduced by 156.1 kg/year. The optimization systems BPVT and CPVT are proposed, and simulation and analysis results show that BPVT is more valuable for further exploration. Compared with the traditional PV system, PVT-PCM system improved the comprehensive utilization rate of solar energy and has a broader research and development prospect.

Are process-intensified extractive distillation always energetically more efficient?

The thermally coupled, dividing wall column, and side-stream configurations are some of the energy-intensified techniques widely applied to the extractive distillation for improving the energy efficiency. Today, several heuristics are available for analysing the energy-saving efficiency of these intensified techniques for ideal distillation system but there is no heuristic available for analysing the complex distillations system. Therefore, it has not yet been established what variables affect the energy-savings and under what particular conditions the intensified processes for these complex distillation systems present energy-savings. In this work, we aim to provide insights and preliminary conclusions that open a field of study for a more detailed and in-depth analysis for future researches through three different case studies where their corresponding intensified configurations do not provide any energy-saving relative to the conventional extractive distillation (CED). Based on our preliminary analysis, we attributed this to the poor values of interconnecting flowrate or composition and high column internal vapour flowrate. Our results also revealed the possibility of extending several heuristics, previously developed for evaluating the energy-saving efficiency in ideal distillation system, for complex distillation. Lastly, several recommendations are given that were derived from our simulation results and the analyses we carried out on existing publications.

Office intelligent lighting system based on the natural lighting and the ZigBee wireless network.

A comfortable and healthy lighting environment cannot only make people comfortable and improve work efficiency, but also avoid visual fatigue caused by the discomfortable lighting environment. In order to solve these problems, this paper proposes an intelligent lighting system that takes natural lighting and the occupancy situation as input and dimming factor K (0<K<1) as output. The linear function between illuminance of the working surface and natural lighting, the occupancy situation, illuminance components of adjacent luminaires, and dimming factor K is obtained through the control algorithm. The simplex method is one of the most commonly used and effective algorithms for solving linear programming problems, so the optimal dimming factor K of each luminaire is obtained. The intelligent lighting system uses the ZigBee tree network structure to transmit the dimming factor to each lamp, making the office lighting environment reach the target value. Opnet is used as a network simulation software to verify system information, such as delay, throughput, and load. The results show that the network transmission delay is only 0.011 s, and the load and throughput are both above 3.0×104bits/s. As an optical software, DIAlux simulates the lighting environment under the control system in two modes: day and night. The results show that the illuminance of the occupied working surface under the system reaches 500l×, and the illuminance of the unoccupied working surface reaches 300l×. The uniformity of illuminance is greater than 0.7. In the day mode, the uniformity of illuminance is improved compared to without any control system. Finally, the energy-saving efficiency of the control system reached 34% and 25% during the day and night, respectively.

Energy-Saving Control Method of Building Central Air Conditioning Based on Genetic Algorithm

In order to solve the problem of huge energy consumption of building central air conditioning, the water system of building central air conditioning was taken as the research object and the genetic algorithm of energy-saving operation and control of building central air conditioning based on MATLAB was designed, so as to build the energy-saving control system model of central air conditioning. On the one hand, the feasibility of the optimized algorithm to solve the energy-saving problem of central air conditioning was proved through the optimization of genetic algorithm. On the other hand, the energy-saving effect was demonstrated through the operation parameters and the variation of air-conditioning energy consumption before and after the experiment. The feasibility and rationality of genetic algorithm to improve the energy-saving effect of central air conditioning was verified by the comparison of the experiment. The results showed that in the design load range of 30%–70%, the average energy-saving rate of central air-conditioning compressor was 16.8%. The maximum energy-saving efficiency was 37.4%, and the minimum energy-saving efficiency was 15.5%. The average energy-saving rate of water system was 26.8%. Therefore, the genetic algorithm had fast convergence speed and high solving accuracy, which was beneficial to improve the energy-saving ability of central air-conditioning water system.

Hydrodynamic Interaction of Two Self-Propelled Fish Swimming in a Tandem Arrangement

Collective locomotion in biological systems is ubiquitous and attracts much attention, and there are complex hydrodynamics involved. The hydrodynamic interaction for fish schooling is examined using two-dimensional numerical simulations of a pair of self-propelled swimming fish in this paper. The effects of different parameters on swimming speed gain and energy-saving efficiency are investigated by adjusting swimming parameters (initial separation distance d0, tail beat amplitude A, body wavelength λ, and period of oscillation T) at different phase difference δϕ between two fish. The hydrodynamic interaction performance of fish swimming in a tandem arrangement is analyzed with the help of the instantaneous vorticity contours, pressure contours, and mean work done. Using elementary hydrodynamic arguments, a unifying mechanistic principle, which characterizes the fish locomotion by deriving a scaling relation that links swimming speed u to body kinematics (A, T, and λ), arrangement of formation (d0), and fluid properties (kinematic viscosity ν), is revealed. It is shown that there are some certain scaling laws between similarity criterion number (Reynolds number (Re) and Strouhal number (St)) and energy-consuming coefficient (CE) under different parameters (Δ). In particular, a generality in the relationships of St–Re and CE–(Re ·Δ) can emerge despite significant disparities in locomotory performance.

Rooftop Greenhouse: (2) Analysis of Thermal Energy Loads of a Building-Integrated Rooftop Greenhouse (BiRTG) for Urban Agriculture

Building-integrated rooftop greenhouses (BiRTGs) are innovative vertical farms consisting of a greenhouse on the roof of a building. BiRTGs can provide environmental benefits by recycling energy, carbon dioxide, and water between the greenhouse and the building. Moreover, BiRTGs can reduce cooling and heating loads by reducing the exposure of the building surface to heat gains/losses through the roof. However, the benefits of BiRTGs have not yet been completely elucidated from an energy perspective. This study aimed to analyse the energy-saving efficiency of BiRTGs using building energy simulations (BES) and computational fluid dynamics (CFD) techniques. BES is a calculation method for analysing the heating and cooling loads of buildings; however, it was difficult to consider time-dependent changes in the ventilation characteristics in the BES model. CFD can be used to calculate more detailed ventilation characteristics of an experimental facility. Thus, CFD and the BES were combined to obtain more accurate BES-based data. The BES-computed annual energy load for a single-span greenhouse in which tomatoes were grown was 490,128 MJ, whereas the annual energy load for growing tomatoes in a BiRTG resulted in a 5.2% reduction, on average (464,673 MJ). The energy-saving effects were positive from October to April because the BiRTG helped transmit heat energy transmitted from the building to the greenhouse. Regarding the total energy load in the BiRTG after alternating the air temperature management (ATM), the heating energy load was reduced in the winter. ATM was expected to apply from November to March, with average energy savings of 11.8%.