Energy and behavioral impacts of integrative retrofits for residential buildings: What is at stake for building energy policy reforms in northern China?

In the early 2000s, the Korean government mandated the construction of only zero-energy residential buildings by 2025 and for non-residential buildings from 2030. Two decades since the start of building energy policy enforcement, Korean experts believe that it is time to evaluate its impact. However, few studies have systematically and extensively examined the energy consumption characteristics of the non-residential building stock. In this study, a framework development is implemented for defining non-residential prototypical office buildings based on Korea’s first large-scale non-residential building survey result from the Korea Energy Economics Institute (KEEI). Then, a detailed building energy model of the defined prototypical building is constructed to verify the model’s energy estimation against observed energy consumption. As an application of the model, a case study for energy policy evaluation utilizing the constructed prototypical building model is presented. Every researcher and county may have their own circumstances when gathering definition data. However, by using the best available representative data, this suggested framework may result in informed decisions regarding energy policy development and evaluation. In addition, the mitigation of greenhouse gases from buildings may be expedited.

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Causes of Quality Failures in Building Energy Renovation Projects of Northern China: A Review and Empirical Study

Energies ◽

10.3390/en13102442 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2442 ◽

Cited By ~ 1

Author(s):

Yuting Qi ◽

Queena Qian ◽

Frits Meijer ◽

Henk Visscher

Keyword(s):

Energy Saving ◽

Time Pressure ◽

Residential Buildings ◽

Northern China ◽

Building Energy ◽

Project Managers ◽

Chinese Government ◽

Skilled Workers ◽

Construction Companies ◽

Building Information

Building energy renovations can effectively improve the environmental performance and energy sustainability of existing buildings. From 2007 onwards, the Chinese government has promoted energy-saving renovations of existing urban residential buildings. Nevertheless, various quality failures happen during the construction period in energy-saving renovation projects of residential buildings. Yet, the causes and their characters remain largely unknown. Through a literature review, this paper investigates the causes of quality failures. Validated through experts’ interviews, a total of 18 causes were identified in building energy renovation projects. These causes were analyzed from two main aspects: the importance of a cause (related to impact and frequency), and the level of effort required to address a cause (related to origin and scale), using both a questionnaire survey and a focus group. The results indicate that the critical causes of quality failures are working under high-cost and high-time pressure, adverse natural conditions, fraud of construction companies, incomplete construction site survey, poor checking procedures of supervisors, poor operational skilled workers, inadequate equipment performance, lack of experienced project managers, and incomplete building information in projects. The causes were classified as external and internal causes of building energy renovation projects. The outcome of this paper should aid policy makers and project coordinators to focus on critical causes of quality failures, and to develop effective actions and policy interventions to achieve successful renovation projects with high-quality performance.

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Analysis of the Effects of Strengthening Building Energy Policy on Multifamily Residential Buildings in South Korea

Sustainability ◽

10.3390/su12093566 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3566

Author(s):

Byung Chang Kwag ◽

Sanghee Han ◽

Gil Tae Kim ◽

Beobjeon Kim ◽

Jong Yeob Kim

Keyword(s):

Energy Consumption ◽

South Korea ◽

Energy Policy ◽

Energy Demand ◽

Residential Buildings ◽

Building Energy ◽

Energy Performance ◽

Primary Energy ◽

Building Envelope ◽

Primary Energy Consumption

The purposes of this study were to overview the building-energy policy and regulations in South Korea to achieve energy-efficient multifamily residential buildings and analyze the effects of strengthening the building design requirements on their energy performances. The building energy demand intensity showed a linear relationship with the area-weighted average U-values of the building envelope. However, improving the thermal properties of the building envelope was limited to reducing the building-energy demand intensity. In this study, the effects of various energy conservation measures (ECMs) on the building-energy performance were compared. Among the various ECMs, improving the boiler efficiency was found to be the most efficient measure for reducing the building-energy consumption in comparison to other ECMs, whereas the building envelope showed the least impact, because the current U-values are low. However, in terms of the primary energy consumption, the most efficient ECM was the lighting power density because of the different energy sources used by various ECMs and the different conversion factors used to calculate the primary energy consumption based on the source type. This study showed a direction for updating the building-energy policy and regulations, as well as the potential of implementing ECMs, to improve the energy performances of Korean multifamily residential buildings.

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Identification of Quality Failures in Building Energy Renovation Projects in Northern China

Sustainability ◽

10.3390/su11154203 ◽

2019 ◽

Vol 11 (15) ◽

pp. 4203 ◽

Cited By ~ 2

Author(s):

Yuting Qi ◽

Queena K. Qian ◽

Frits M. Meijer ◽

Henk J. Visscher

Keyword(s):

Residential Buildings ◽

Northern China ◽

Building Energy ◽

Energy Sustainability ◽

Design Work ◽

Construction Companies ◽

Technical Requirements ◽

Crucial Problem ◽

Preparation Stage ◽

The Government

Building energy renovations contribute significantly to energy sustainability and environmental protection. These advantages have increased the importance of renovating existing residential buildings in many countries. In China, the government has supported the energy-saving renovation of existing urban residential buildings since 2007. However, quality failures, which do not meet the technical requirements, occur during construction processes in building energy renovation projects. Although quality failures are regarded as a crucial problem in building energy renovation projects, the identification of quality failures and their sources, likelihood, impacts, and causes remain mostly unknown. This paper investigates the nature of quality failures in building energy renovation projects. A total of 25 quality failures were first identified through five cases, and interviews with six experienced construction professionals in China. A questionnaire survey was further conducted to evaluate the frequency of quality failures. The results show the nature of quality failures that arise during construction and their sources, occurrence frequency, causes, and impacts. The research reveals that quality failures are caused by defaults by workers; inadequate checking procedures; incomplete construction site surveys; inaccurate design work; fraud of construction companies; and inefficient cooperation between different departments. Above all, the behaviors of the main actors are responsible for poor construction quality. Additionally, emphasis on quality control during the renovation preparation stage is critical to ensure that quality failures are reduced in numbers and severity.

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Application Method of a Simplified Heat and Moisture Transfer Model of Building Construction in Residential Buildings

Energies ◽

10.3390/en14144180 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4180

Author(s):

Joowook Kim ◽

Michael Brandemuehl

Keyword(s):

Latent Heat ◽

Moisture Transfer ◽

Residential Buildings ◽

Building Energy ◽

The United States ◽

Building Envelope ◽

Outdoor Environment ◽

Transfer Model ◽

Heat And Moisture Transfer ◽

Heat And Moisture

Several building energy simulation programs have been developed to evaluate the indoor conditions and energy performance of buildings. As a fundamental component of heating, ventilating, and air conditioning loads, each building energy modeling tool calculates the heat and moisture exchange among the outdoor environment, building envelope, and indoor environments. This paper presents a simplified heat and moisture transfer model of the building envelope, and case studies for building performance obtained by different heat and moisture transfer models are conducted to investigate the contribution of the proposed steady-state moisture flux (SSMF) method. For the analysis, three representative humid locations in the United States are considered: Miami, Atlanta, and Chicago. The results show that the SSMF model effectively complements the latent heat transfer calculation in conduction transfer function (CTF) and effective moisture penetration depth (EMPD) models during the cooling season. In addition, it is found that the ceiling part of a building largely constitutes the latent heat generated by the SSMF model.

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Evaluation of Urban-Scale Building Energy-Use Models and Tools—Application for the City of Fribourg, Switzerland

Sustainability ◽

10.3390/su13041595 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1595

Author(s):

Valeria Todeschi ◽

Roberto Boghetti ◽

Jérôme H. Kämpf ◽

Guglielmina Mutani

Keyword(s):

Machine Learning ◽

Energy Use ◽

Residential Buildings ◽

Building Energy ◽

Energy Performance ◽

Space Heating ◽

Engineering Model ◽

Building Energy Use ◽

The Impact ◽

The City

Building energy-use models and tools can simulate and represent the distribution of energy consumption of buildings located in an urban area. The aim of these models is to simulate the energy performance of buildings at multiple temporal and spatial scales, taking into account both the building shape and the surrounding urban context. This paper investigates existing models by simulating the hourly space heating consumption of residential buildings in an urban environment. Existing bottom-up urban-energy models were applied to the city of Fribourg in order to evaluate the accuracy and flexibility of energy simulations. Two common energy-use models—a machine learning model and a GIS-based engineering model—were compared and evaluated against anonymized monitoring data. The study shows that the simulations were quite precise with an annual mean absolute percentage error of 12.8 and 19.3% for the machine learning and the GIS-based engineering model, respectively, on residential buildings built in different periods of construction. Moreover, a sensitivity analysis using the Morris method was carried out on the GIS-based engineering model in order to assess the impact of input variables on space heating consumption and to identify possible optimization opportunities of the existing model.

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Decarbonization of Residential Building Energy Supply: Impact of Cogeneration System Performance on Energy, Environment, and Economics

Energies ◽

10.3390/en14092538 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2538

Author(s):

Praveen K. Cheekatamarla

Keyword(s):

Carbon Dioxide ◽

Power Generation ◽

Energy Consumption ◽

Carbon Footprint ◽

Residential Buildings ◽

Building Energy ◽

Primary Energy ◽

Primary Energy Consumption ◽

Cogeneration System ◽

The Impact

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.

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Modifying Building Energy-Saving Design Based on Field Research into Climate Features and Local Residents’ Habits

Energies ◽

10.3390/en14020442 ◽

2021 ◽

Vol 14 (2) ◽

pp. 442

Author(s):

Xiaoyue Zhu ◽

Bo Gao ◽

Xudong Yang ◽

Zhong Yu ◽

Ji Ni

Keyword(s):

Energy Consumption ◽

Energy Saving ◽

Residential Buildings ◽

Average Energy ◽

Field Tests ◽

Building Energy ◽

Building Energy Efficiency ◽

Local Conditions ◽

Building Energy Saving ◽

Average Energy Consumption

In China, a surging urbanization highlights the significance of building energy conservation. However, most building energy-saving schemes are designed solely in compliance with prescriptive codes and lack consideration of the local situations, resulting in an unsatisfactory effect and a waste of funds. Moreover, the actual effect of the design has yet to be thoroughly verified through field tests. In this study, a method of modifying conventional building energy-saving design based on research into the local climate and residents’ living habits was proposed, and residential buildings in Panzhihua, China were selected for trial. Further, the modification scheme was implemented in an actual project with its effect verified by field tests. Research grasps the precise climate features of Panzhihua, which was previously not provided, and concludes that Panzhihua is a hot summer and warm winter zone. Accordingly, the original internal insulation was canceled, and the shading performance of the windows was strengthened instead. Test results suggest that the consequent change of SET* does not exceed 0.5 °C, whereas variations in the energy consumption depend on the room orientation. For rooms receiving less solar radiation, the average energy consumption increased by approximately 20%, whereas for rooms with a severe western exposure, the average energy consumption decreased by approximately 11%. On the other hand, the cost savings of removing the insulation layer are estimated at 177 million RMB (1 USD ≈ 6.5 RMB) per year. In conclusion, the research-based modification method proposed in this study can be an effective tool for improving building energy efficiency adapted to local conditions.

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A Rapid Review on Community Connected Microgrids

Sustainability ◽

10.3390/su13126753 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6753

Author(s):

Moiz Masood Syed ◽

Gregory M. Morrison

Keyword(s):

Literature Review ◽

Urban Areas ◽

Energy Use ◽

Residential Buildings ◽

Optimal Solution ◽

Building Energy ◽

Rapid Review ◽

Solar Pv ◽

Electricity Cost ◽

Building Energy Use

As the population of urban areas continues to grow, and construction of multi-unit developments surges in response, building energy use demand has increased accordingly and solutions are needed to offset electricity used from the grid. Renewable energy systems in the form of microgrids, and grid-connected solar PV-storage are considered primary solutions for powering residential developments. The primary objectives for commissioning such systems include significant electricity cost reductions and carbon emissions abatement. Despite the proliferation of renewables, the uptake of solar and battery storage systems in communities and multi-residential buildings are less researched in the literature, and many uncertainties remain in terms of providing an optimal solution. This literature review uses the rapid review technique, an industry and societal issue-based version of the systematic literature review, to identify the case for microgrids for multi-residential buildings and communities. The study describes the rapid review methodology in detail and discusses and examines the configurations and methodologies for microgrids.

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Investigating Primary Factors Affecting Electricity Consumption in Non-Residential Buildings Using a Data-Driven Approach

Energies ◽

10.3390/en12214046 ◽

2019 ◽

Vol 12 (21) ◽

pp. 4046 ◽

Cited By ~ 3

Author(s):

Sooyoun Cho ◽

Jeehang Lee ◽

Jumi Baek ◽

Gi-Seok Kim ◽

Seung-Bok Leigh

Keyword(s):

Energy Consumption ◽

Energy Use ◽

Simulation Analysis ◽

Residential Buildings ◽

Electric Energy ◽

Electricity Consumption ◽

Building Energy ◽

Major Effect ◽

Measuring Instruments ◽

Building Energy Consumption

Although the latest energy-efficient buildings use a large number of sensors and measuring instruments to predict consumption more accurately, it is generally not possible to identify which data are the most valuable or key for analysis among the tens of thousands of data points. This study selected the electric energy as a subset of total building energy consumption because it accounts for more than 65% of the total building energy consumption, and identified the variables that contribute to electric energy use. However, this study aimed to confirm data from a building using clustering in machine learning, instead of a calculation method from engineering simulation, to examine the variables that were identified and determine whether these variables had a strong correlation with energy consumption. Three different methods confirmed that the major variables related to electric energy consumption were significant. This research has significance because it was able to identify the factors in electric energy, accounting for more than half of the total building energy consumption, that had a major effect on energy consumption and revealed that these key variables alone, not the default values of many different items in simulation analysis, can ensure the reliable prediction of energy consumption.

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