Reinforcement Learning Model for Energy System Management to Ensure Energy Efficiency and Comfort in Buildings

This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within buildings.Enhancing the comfort of living or working in buildings often necessitates increased consumption of energy and material,such as for thermal upgrades,which consequently incurs additional economic costs.It is crucial to acknowledge that such improvements do not always lead to a decrease in total pollutant emissions,considering emissions across all stages of production and usage of energy and materials aimed at boosting energy efficiency and comfort in buildings.In addition,it explores the methods and mechanisms for modeling the operating modes of electric boilers used to collectively improve energy efficiency and indoor climatic conditions.Using the developed mathematical models,the study examines the dynamic states of building energy supply systems and provides recommendations for improving their efficiency.These dynamic models are executed in software environments such as MATLAB/Simscape and Python,where the component detailing schemes for various types of controllers are demonstrated.Additionally,controllers based on reinforcement learning(RL)displayed more adaptive load level management.These RL-based controllers can lower instantaneous power usage by up to 35%,reduce absolute deviations from a comfortable temperature nearly by half,and cut down energy consumption by approximately 1%while maintaining comfort.When the energy source produces a constant energy amount,the RL-based heat controllermore effectively maintains the temperature within the set range,preventing overheating.In conclusion,the introduced energydynamic building model and its software implementation offer a versatile tool for researchers,enabling the simulation of various energy supply systems to achieve optimal energy efficiency and indoor climate control in buildings.

Effect of building energy efficiency standards on carbon emission efficiency in commercial buildings

The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,exploring the provincial variations in carbon emission efficiency(CEE)in the building sector and identifying the effect of BEESs on CEE is crucial.This study focuses on commercial buildings in China and applies a difference in differences model to evaluate the impact of BEESs on the CEE of commercial buildings.The slacks-based measure–data envelopment analysis model is employed to assess the CEE of commercial buildings in 30 Chinese provinces from 2000 to 2019.Furthermore,heterogeneous tests are used to explore how climate characteristics and economic conditions affect the efficiency of BEESs.The results indicate that BEESs positively influence the CEE of commercial buildings.Specifically,a 1%increase in the intensity of BEESs causes a 0.1484%increase in the CEE of commercial buildings.Moreover,the impact of BEESs is particularly pronounced in the southern and western provinces.This study provides valuable scientific evidence for governments to enhance BEESs implementation.

eQUEST Based Building Energy Modeling Analysis for Energy Efficiency of Buildings

Building energy performance is a function of numerous building parameters.In this study,sensitivity analysis on twenty parameters is performed to determine the top three parameters that have the most significant impact on the energy performance of buildings.Actual data from two fully operational commercial buildings were collected and used to develop a building energy model in the Quick Energy Simulation Tool(eQUEST).The model is calibrated using the Normalized Mean Bias Error(NMBE)and Coefficient of Variation of Root Mean Square Error(CV(RMSE))method.The model satisfies the NMBE and CV(RMSE)criteria set by the American Society of Heating,Refrigeration,and Air-Conditioning(ASHRAE)Guideline 14,Federal Energy Management Program(FEMP),and International Performance Measurement and Verification Protocol(IPMVP)for building energy model calibration.The values of the parameters are varied in two levels,and then the percentage change in output is calculated.Fractional factorial analysis on eight parameters with the highest percentage change in energy performance is performed at two levels in a statistical software JMP.For building A,the top 3 parameters from the percentage change method are:Heating setpoint,cooling setpoint and server room.From fractional factorial design,the top 3 parameters are:heating setpoint(p-value=0.00129),cooling setpoint(p-value=0.00133),and setback control(p-value=0.00317).For building B,the top 3 parameters from both methods are:Server room(pvalue=0.0000),heating setpoint(p-value=0.00014),and cooling setpoint(p-value=0.00035).If the best values for all top three parameters are taken simultaneously,energy efficiency improves by 29%for building A and 35%for building B.

Low-Cost Insulation for Energy Efficient Buildings in Terai Region of Nepal

There is a huge amount of energy savings potential in public building sector that has yet to be realized.By prioritizing energy efficiency in its own buildings and thus promoting the development of required knowledge in terms of new technology and construction methods,the public sector will lead the way in efforts to increase the rate of renovations.The low-cost insulation strategies and a comparison of cost with existing insulation materials has been described in this study.We have repeatedly faced energy crises and will continue to do so in the future if appropriate action is not taken in a timely manner.Properly implementing energy-saving initiatives in for achieving thermal comfort in buildings as well as reducing the energy costs would undoubtedly inspire the residential sector,resulting in significant reductions in energy usage.Simulations were carried out to study insulation layers on various building components like exterior walls,floor and roofs,generating different scenarios for a building as a base model,which were then compared and analysed to verify the literature used to develop the cases.The proposed recommendations,which have been validated,are certain to increase building energy efficiency,achieve thermal comfort in low cost than what is currently being used.

Assessment of Compliance to Building Energy Efficiency Strategies in the Development of Housing Estates in FCC, Abuja Nigeria

Compliance to local energy efficiency strategies can significantly reduce energy consumption in buildings and promote sustainability. However, Nigeria Building Energy Efficiency Code (BEEC) seems to be just paper work without enforcement or compliance. Assessment of Compliance to Green Building Energy Efficiency Strategies in the Development of Housing Estates in FCC, Abuja Nigeria was carried out. The compliance of estate buildings to BEEC in the study area was assessed;and the aspects of the building energy efficiency strategies with more compliance were determined. Data were mainly from primary sources such as questionnaire survey, interview with key informants and observation. The study population included all estate developers and building construction professionals. Data were gathered from one hundred and fifty (150) building professionals through questionnaire administration. Data collected were analysed using Z score and ANOVA and presented in tables. Results show that only 18% of respondents agreed that building complied with BEEC, and the Z score for positive affirmation is below average score. There is a significant difference in the integration of different energy efficient management strategies in the estates’ construction at 95% confidence level. The integration of measures such as window to wall ratio and window shading’ were significantly higher than other BEEC strategies such as roof insulation and minimal air condition unit (≤EER/COP of 2.8). Thus, the development of estates in FCC Abuja did not achieve energy efficiency.

Benchmarking of energy efficiency standards for residential buildings in China

In order to benchmark the energy efficiency standards for residential buildings in China,the Hong Kong building environment assessment method（HK-BEAM）is chosen as the compliance criteria for assessment.The annual energy consumption and the overall thermal transfer value（OTTV）of a baseline residential building prescribed in the Chinese codes and the HK-BEAM are evaluated and compared by the energy budget approach.The results show that in the Chinese codes,the OTTV of the residential building is lower,but the annual energy consumption and the cooling load are higher than those in the HK-BEAM.The annual energy use difference amounts to 13.4%.All the compliance criteria except the ventilation rate and the equipment power in the Chinese codes are set higher than those in the HK-BEAM.However,the compliance criteria of the ventilation rate and the equipment power,especially the ventilation rate,result in much energy consumption,which ultimately induces a high energy budget for residential buildings.

Weighting indicators of building energy efficiency assessment taking account of experts' priority

Analytic hierarchy process(Group AHP) is combined with two different methods of assigning experts' priority to weight indicators in building energy efficiency assessment.One is to assign the experts' priority averagely,and the other is to use cluster analysis to assign experts' priority.The results show that,1) Different expert's priority assigns result in great different weights of indicators in building energy efficiency assessment,therefore,the method of assigning experts' priority should be taken into account carefully while weighting indicators of building energy efficiency assessment using Group AHP;2) Three indicators are found to be overwhelmingly important in residential building energy efficiency assessment in the hot summer and cold winter zone in China.They are 'Outdoor & indoor shadow','Heating & air-conditioning facilities' and 'Insulation of envelope';3) The method combining cluster analysis with Group AHP to weight indicator of building energy efficiency assessment has the advantage of finding overwhelming important indicator,whereas,some less important indicators have a tendency to be ignored.A useful reference is provided for building energy conservation including policy revision and energy efficient residential building design.

Country-level meteorological parameters for building energy efficiency in China

Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal engineering design,heating ventilation and air conditioning design,and energy consumption simulations.Focusing on the key issues such as low spatial coverage and the lack of daily or higher time resolution data,daily and hourly models of the surface meteorological data and solar radiation were established and evaluated.Surface meteorological data and solar radiation data were generated for 1019 cities and towns in China from 1988 to 2017.The data were carefully compared,and the accuracy was proved to be high.All the meteorological parameters can be assessed in the building sector via a sharing platform.Then,country-level meteorological parameters were developed for energy-efficient building assessment in China,based on actual meteorological data in the present study.This set of meteorological parameters may facilitate engineering applications as well as allowing the updating and expansion of relevant building energy efficiency standards.The study was supported by the National Science and Technology Major Project of China during the 13th Five-Year Plan Period,named Fundamental parameters on building energy efficiency in China,comprising of 15 top-ranking universities and institutions in China.

Promoting energy efficiency reconstruction for existing buildings based on comprehensive benefit evaluation

The purpose of the comprehensive benefit evaluation of the existing building energy saving renovation project is to promote the healthy development of the energy saving reconstruction. Therefore, it is necessary to reflect the value and function of incentive and restraint. The concrete embodiment is that: improving energy saving standard renovation of existing buildings, promoting the construction of energy efficiency labeling system, and strengthening the construction of government supervision system by the comprehensive benefit evaluation.

Understanding occupancy pattern and improving building energy efficiency through Wi-Fi based indoor positioning

Detailed visualisation and data analysis of occupancy patterns including spatial distribution and temporal variations are of great importance to delivering energy efficient and productive buildings. An experimental study comprising 24-h monitoring over 30 full days was conducted in a university library building.Occupancy profiles have been monitored and analysis has been carried out. Central to this monitoring study is the Wi-Fi based indoor positioning system based on the measured Wi-Fi devices' number and locations and data mining methods. Distinct from traditional occupancy and energy studies,more detailed informationrelated to the indoor positions and number of occupants has offered a better understanding of building user behaviour. The implication of the occupancy patterns for energy( e. g. lighting and other building services) efficiency is assessed,assisted with data from lighting sensors where needed. It is found occupancy patterns change dramatically with time. Also,the energy waste patterns have been identified through the method of data association rule mining. If the identified energy waste is removed,the total energy consumption can be reduced by 26. 1%. The indoor positioning information also has implications for optimizing space use,opening hours as well as staff deployment. The work could be extended to more rooms with diverse functions,other seasons and other types of non-domestic buildings for a more comprehensive understanding of building user behaviour and energy efficiency.

A New Type of Paper-frame Cavernous Material and Its Application in Energy Efficiency in Buildings

This paper introduces a new type of paper-frame cavernous material, which is a made-up hollow material, by using silicate-cinder size to drench and daub. It possesses excellent performances such as light-weight, high-intensity, fire-resistance, sound-insulation, heat-insulation and no-pollution. Composed with concrete materials, a new type of bearing and energy-efficient block can be gained, which is kind of excellent wall materials and has a wide application prospect.

Model Establishment of Whole Life Cycle for Energy Efficiency of Rural Residential Buildings in Northern China

The building energy efficiency is determined by the climatic region and the energy-saving measures. In this paper an assessment model for energy efficiency of the rural residential buildings in the northern China was established by the method of whole life cycle. The energy consumption of the rural residential buildings in different stages was analyzed through quantitative method in this model. At the same time, the corresponding energy efficiency assessment system was developed.

Optimisation of Direct Expansion (DX) Cooling Coils Aiming to Building Energy Efficiency

Efficient Air Conditioning (A/C) system is the key to reducing energy consumption in building operation. In order to decrease the energy consumption in an A/C system, a method to calculate the optimal tube row number of a direct expansion (DX) cooling coil for minimizing the entropy generation in the DX cooling which functioned as evaporator in the A/C system was developed. The optimal tube row numbers were determined based on the entropy generation minimization (EGM) approach. Parametric studies were conducted to demonstrate the application of the analytical calculation method. Optimal tube row number for different air mass flow rates, inlet air temperatures and sensible cooling loads were investigated. It was found that the optimal tube row number of a DX cooling coil was in the range of 5 - 9 under normal operating conditions. The optimal tube row number was less when the mass flow rate and inlet air temperature were increased. The tube row number increased when the sensible cooling load was increased. The exergy loss when using a non-optimal and optimal tube row numbers was compared to show the advantage of using the optimal tube row number. The decrease of exery loss ranged from around 24% to 70%. Therefore the new analytical method developed in this paper offers a good practice guide for the design of DX cooling coils for energy conservation.

Sensibility Analysis of the Brazilian Standards for Energy Efficiency Regarding the Variation of Internal Load Density in Office Buildings in Brazilian Bioclimatic Zones 1 and 7

The RTQ-C （Technical Requirements of Quality for the Energy Performance Level of Commercial Buildings） publication classified the buildings in five efficiency levels. In RTQ-C, the evaluation can be done with two methods： a prescriptive method and a simulation one. This paper aims to identify the sensibility of the prescriptive method RTQ-C regarding the variation of equipment internal load density in office buildings in bioclimatic Zones I and 7 of the Brazilian bioclimatic zoning. The research results show that the building with walls and roof configured to meet specific prerequisites for energy efficiency Levels B and C had a lower consumption than buildings that meet the prerequisites to Level A. The study also showed that buildings with high internal load density of equipment, maximum shape factor and high, with walls and roofs with higher thermal transmittance, have lower power consumption than constructions with an envelope with greater thermal resistance. The increase in internal load density causes an increase in the internal heat generated by the large amount of equipment. In buildings with higher thermal insulation （Level A）, the internal heat is maintained in the environment, causing overheating and the need for an air conditioning system.

Energy Efficiency and Renewable Energy Technologies Using Smart Grids: Study Case on NIPE Building at UNICAMP Campus

In its broadest interpretation, the smart grid vision sees the future of power industry transformed by the introduction of intelligent two-way communications, ubiquitous metering and measurement. This enables much finer control of energy flows and the integration and efficient use of renewable forms of energy, energy efficiency methodologies and technologies, as well as many other advanced technologies, techniques and processes that wouldn’t have been practicable until present. The smart grid vision also enables the creation of more reliable, more robust and more secure power supply infrastructure, and helps optimize the enormous investments required to build and operate the physical infrastructure required. The smart grid promises to revolutionize the electric power business that has been in place for the past 75 years. This work discusses the efficiency, targeted at the consumer units of electricity, with a view to sustainability and potential for technological innovation. The issue is addressed from two perspectives: the systems for generation and power distribution, and the design of a building “smart energy”. Because of the novelty of the subject in our country, the concepts presented and treated throughout this work come from material obtained at events and specialized sites on electric power system in Brazil and worldwide, being accompanied by information and data from NIPE’s building at University of Campinas’s campus case study in which it exemplifies the applicability of the techniques and recommended technologies.

Government regulation practices and issues on building energy efficiency in China

This paper analyzes the government control of building energy efficiency in China from the aspects of policies and regulations, technical standards, pilot demonstration projects and economic means, and expounds the characteristics and problems of government regulation practice in China. It is found that the government regulation of building energy conservation in our country has some problems, such as imperfect system, weak incentive policy, imperfect management system, and the lack of public participation. Through the deep analysis of the existing problems, it is pointed out that the fundamental reason for the poor operation of China's building energy efficiency market lies in the lack of understanding of the building energy efficiency market, the lack of government administrative functions and the weak consciousness of the main body.

A Review of Building Energy Efficiency Technology

In China, there’s high energy consumption in buildings with less attention to building energy efficiency. All of these facts prove that there are great potentialities in energy conservation. On account of this, this paper introduces multiple building energy-saving technologies at home and abroad, including the technologies for innovative wall materials, exterior wall external insulation, heat insulation of window, utilization of solar energy, heat storage and recovery as well as the illumination energy saving technology. On the basis of new buildings, this paper gives five suggestions on building energy efficiency. Meanwhile it raises five suggestions on energy conservation based on the existing building, for which it presents purposely the technologies and measures about energy saving transformation from four aspects.

Indicators of Energy Efficiency in Buildings. Comparison with Standards in Force in Argentina

In this work we make a comparative study of the energy behaviour in different building types. We analyze three cases of office buildings and three residential buildings, and compare them with a previous sample. We seek to find correlations or differences in behavior in terms of potential energy losses and gains, and UL values compared with Argentinian Standards to verify the degree of efficiency. For energy analysis we used a software which allows the analysis of thermal and energy building performance at steady state on a monthly basis. This software is called EnergoCAD and it also determines formal indicators based on IRAM standards. We conclude that the indicators used are clear to energetically “grade” buildings and to facilitate comparisons. In turn, smaller buildings are relatively less energy efficient than larger ones. At the same time it is noteworthy that the energy inefficiency has been growing rapidly over the years. Finally it is noted that none of the cases analyzed meets the National Standards.

The Study of Thermal Mass as a Passive Design Technique for Building Comfort and Energy Efficiency

The day/night （diurnal） changes in temperature and solar radiation pose challenges for maintaining human thermal comfort in buildings. Passive and energy-conserving buildings seek to manage the available thermal energy by lowering peaks and dampening the fluctuations in order to maintain conditions for human comfort. Appropriate use of thermal mass moderates the internal temperatures by averaging diurnal extremes. Thermal mass is one of the powerful tools which architects and designers can use to control temperature. It can be used to optimize the performance of energy-conserving buildings that rely primarily on mechanical heating and cooling strategies. Massive building envelopes-such as masonry, concrete, earth, and insulating concrete forms （ICFs） can be utilized as one of the simplest ways of reducing building heating and cooling loads. This article analyses the role and effectiveness of thermal mass as a strategy for providing indoor thermal comfort for passive solar and energy conserving buildings.

Evaluation of Radon Indoor Pollution Risk in High Efficiency Energy Buildings

The target of achieving high energy efficiency standard in order to comply with the EU Directives is leading to remarkable efforts to improve the performance of the building envelope. Excellent thermal insulation and airtight sealing of leakages are of the utmost importance to fulfil the expected targets. Unfortunately, airtightness produces the negative effect of increasing the indoor concentration of air pollutants like radon. Despite the seriousness of the problem is generally misconceived, long-term exposition to radon is acknowledged to be the second cause of lung cancer after smoke. The paper outlines the implications for the building sector and focuses on design and preventive criteria as well as on mitigation and remedial techniques.