Commercial Building Sector Research Articles

Demonstration of the carbon capture with building make-up air unit

Building-integrated carbon capture technology has the potential to reduce the cost of CO2 capture while improving indoor air quality (IAQ). To promote the adoption of CO2 capture in a building environment, this study investigated the possibility of integrating carbon capture technology with an existing rooftop make-up air unit (MAU) system to trap CO2. Here, a modular compact CO2 capture system containing amine-functionalized polymer fibers was examined. The system, which was installed at the exhaust of the MAU, captures CO2 before it leaves the building to enter the atmosphere as a greenhouse gas. The demonstrated average amount of CO2 captured was 1.1–1.4 mmol/g of adsorbent material. Techno-economic analysis (TEA) was further performed on the CO2 capture system, considering material costs, energy costs, as well as transportation and regeneration costs. These results were then used to estimate the levelized cost per ton CO2 captured (LCOC). To achieve LCOC below $100/t-CO2, adsorbents should have working capacities of 4.9 t and 3 t-CO2/year for 5 years and 10 years of operation, respectively. In summary, this study highlights a viable path toward the decarbonization of the commercial buildings sector and provides quantitative performance and economic insight on the suitability of building-integrated carbon capture technology.

Analysis Of Battery LiFePO4 Pack Capacity As An Alternative Energy Source In Water Pump Shimizu PS-135 E

Electrical energy is a basic need for society and is a fairly economical resource that can be used for various activities. Human activities are supported by electrical energy. Electrical energy has important role in supporting all activities such as the industrial, commercial building, transportation and housing sectors. Water pump Shimizu PS-135 E is a type of water pump that is widely used in family activities, its function is to supply water from water sources (reservoirs, wells) for family needs such as bathing and washing. The pump relies continuously use of electrical energy, it means that, if this energy source runs out, the pump will not be able to operate automatically and ultimately. For this reason, in this research, the LiFePO4 type battery is used as an alternative energy source to overcome the above problems. The results of the analysis in this research show that to run the water pump for 1.5 hours a 42,000 mAh 12 Volt LiFePO4 battery is required which is arranged in a 4S - 7P manner and as a battery protector a 60 A Daly type BMS is used. Testing the load on the water pump until the battery cut time showed that the battery drain time was 1.3 hours, the battery condition was 20% with a voltage of 12.89 Volts. AC output voltage 230.4 Volts, current 1.145 A, power (P) = 195 Watts, Power Factor 0.72. The volume of water produced in 1.3 hours (78 minutes) is 2,182 liters.

Low-speed wind energy generation devices to facilitate NZEB in urban Pakistan

Energy consumption and its resultant impact on climate change are inextricably linked, with the burning of fossil fuels being a chief contributor to greenhouse gas emissions, furthering global warming. Mitigating these effects necessitates a two-fold approach: reducing energy consumption through enhanced efficiency and behavioral modifications, and concurrently transitioning to renewable and clean energy sources. Of particular concern is the domestic and commercial building sector, which currently accounts for a substantial 40% of the world's total energy usage. Conventional wind turbines, effective in harnessing wind energy, face limitations in urban areas due to the requisite wind speeds. Micro wind turbines, notably Vertical Axis Wind Turbines (VAWT), present a promising solution for achieving net-zero energy buildings in urban settings. VAWTs exhibit advantages such as higher efficiency and lower cut-in speeds. Despite their promise, challenges like reliability, cost, and environmental impact persist. This concise overview suggests potential applications for Pakistan, emphasizing the imperative for further exploration in optimizing VAWT design, developing hybrid systems, and evaluating societal acceptance of rooftop wind farms.

Historical carbon peak situation and its driving mechanisms in the commercial building sector in China

Evaluating the peak situation of commercial building carbon emissions (CBCE) at the provincial level and revealing their differentiated driving mechanisms are extremely significant for achieving the national “Dual carbon” target. In this study, a new provincial-level carbon peak situation assessment model is constructed to evaluate the historical CBCE peak situations in China by integrating conditional judgement function, Mann-Kendall trend test, and Tapio decoupling model. Furthermore, the STIRPAT model and grouped regression model are combined to investigate the driving mechanisms on CBCE under different carbon peaking situations. Results showed that the CBCE in Beijing have reached the peak, and Shandong and Inner Mongolia have entered the peak potential period. Beijing achieved the decoupling of CBCE from value added of tertiary sector and floor space per capita. The most important factors leading to different peak situations of CBCE are commercial floor space per capita and energy intensity. Urban population, industrial structure, value added of tertiary industry per capita and energy structure show different degrees of influence on different peak stages of CBCE. This study provides a general methodology for evaluating the carbon peak situation and its driving mechanism. It sets the foundation for the formulation of the differentiated carbon peak pathway and provides a reference for the carbon emission assessment of other countries with regional carbon peak differences in the world.

Heating electrification in cold climates: Invest in grid flexibility

One strategy to significantly reduce greenhouse gas emissions in end-use sectors such as building heat is to switch from fossil fuels to electricity. To date, electricity consumption follows a regular and predictable pattern; however, electrifying building heat, which is driven by ambient temperature, causes this pattern to change. Previous work has not fully addressed the implications of building heat electrification on the timing and magnitude of peak demands and on flexibility requirements of the electricity grid. In this work, a high-resolution heating demand model, featuring building stock turnover forecasts, is developed, and applied to British Columbia. The study determines energy, capacity, and flexibility requirements by computing regional energy load profiles for space and water heat. Six scenarios were developed to examine the decarbonization potential in the residential and commercial building sector, considering increased heat pump adoption, building envelope energy efficiency improvements, and the implementation of building energy codes. With an emphasis on building stock improvements, 90% heat pump penetration results in only 6% increase in electrical energy even with an annual population growth rate of 1.1%; however, this scenario leads to a 37% increase in peak electricity demand. Over the time-period considered, building energy codes and retrofit rates contribute relatively little to achieving net-zero emissions in the buildings sector, while building heat electrification has significant impacts on future flexibility requirements of the electricity grid.

Experimental validation of thermochemical water-sorption materials for thermal energy storage: Building application

Salt hydrates for seasonal heat storage have emerged as an important research topic due to their potential to fulfil the heat demand in the residential and commercial building sector. However, the research undertaken has not yet covered key aspects of their fundamental thermal behaviour understanding e.g. experimentally validation, characterisation methodologies or material screening. The present investigation is aimed to identify promising thermochemical materials in the temperature range of 25–150°C, which are suitable for building applications and waste heat recovery. A list of ten salt hydrates has been screened through an experimental validation, which was developed and optimized for the specific working conditions. The salt hydrates were tested under operational conditions and key properties are assessed (thermal conductivity, specific heat, volume change, etc). Different case studies were used to narrow down to a list of final salts candidates under three theoretical working conditions scenarios for both open and closed systems. The cases of study prioritised high energy density (after one hydration/dehydration cycle), acceptable volume expansion and stability, which led to the final candidates. Magnesium sulphate was selected in the case of high energy density (>2 MJ/m3) and low cost (1 €/MJ), when lowering the energy density to 1 MJ/m3 calcium sulphate and copper sulphate were revealed as promising candidates for open and closed systems. While calcium nitrate was identified as a candidate along with magnesium sulphate when considering closed systems.

How Building Energy Use Reacted to Variable Occupancy Pre- and Post- COVID-19 Pandemic—Sensitivity Analysis of 35 Commercial Buildings in Canada

The COVID-19 pandemic and global shutdown and work-from-home order for non-essential businesses and employees led to a substantial decline in energy usage in the commercial building sector. However, the magnitude of decline was not equivalent to what would be expected for unoccupied spaces. The energy performance of low/unoccupied commercial buildings, particularly in the context of new minimum requirements to maintain indoor air quality, is an intriguing research question. In this study, we developed a numerical model that measures electricity usage sensitivity to occupancy (ESTO) where we compare the business-as-usual energy performance with unoccupied energy performance. Two years of COVID-time (in addition to a pre-COVID control year) hourly energy use (electricity (plug loads, lighting, and fans), heating, and cooling) using data from 35 commercial buildings (i.e., buildings with HVAC and other building systems typical of commercial rather than residential buildings) are analyzed to quantify those changes. A change point model is used to assess thermal load intensities, change point temperature, and off-season unoccupied baseloads. Finally, we suggest a generic framework for building scoring based on selected performance parameters. Results indicate that the suggested scoring system is robust and replicable and is reliable for ranking buildings within a given portfolio from best- to worst- performing, thus prioritizing buildings that are best candidates for retrofits.

Servitization and construction industry: ideas and insights from the commercial building sector

Servitization, which can be defined as the combination of products and services in a single integrated solution, has been a topic attracting attention from scholars and managers all around the globe. Despite this, very few studies have proposed to analyse this phenomenon on the construction industry. Thus, this research objective is to fill this gap by evaluating how the construction companies from the commercial building sector are applying servitization to their business offers and what are the impacts of this application on their immediate network of suppliers and clients. With this objective in sight, it was performed a case study of three cases where servitization was being applied. The study analysed three networks (two dyads and on triad) of suppliers and clients of servitization. From the findings, it can be said that servitization brought results similar than found in other industries, such as differentiation and new streams of revenue. It also changed the cost structure of the offer, allowing for transferring part of the CAPEX to OPEX, and reducing of total costs involved. This work helps to understand how servitization is impacting the commercial building sector and, consequently, part of the construction industry as a whole.

Pengaruh Kompensasi dan Pemberian Bonus Terhadap Kepuasan Kerja dan Kinerja Karyawan PT. Adhi Persada Properti Surabaya

PT. Adhi Persada Properti is a subsidiary of PT. Adhi Karya. The company is engaged in the residential, commercial building and property management sectors. This company was created in 1993. This study aims to find out the relationship between compensation and bonus distribution on job satisfaction and employee performance of PT. Adhi Persada Properti Surabaya branch. The approach of this research is quantitative, while the sampling in this study is a saturated sample where a total of 36 employees of PT. Adhi Persada Properti Surabaya as respondents. The data in this study were analyzed using the Statistical Program for Social Science (SPSS) version 23 software on computer. Further research shows that compensation and bonus distribution have a significant positive relationship on job satisfaction while job satisfaction has a significant positive relationship on employee performance. The results of the study provide conclusion that the more satisfied employees with compensation and bonuses provided by the company, the employees will be more diligent in working.

Dynamic facade control systems for optimal daylighting, a case of Kerala

Natural daylighting of the building interiors contributes to better environmental quality and reduced energy consumption. Buildings in the tropical region require direct cut-off from irradiance to control internal thermal gain. More extensive fenestration may contribute towards more internal thermal gain because of an improper form of facade or shading systems, which may further contribute to the need for more cooling load in air conditioning. The commercial building sector consumes more energy due to the significance of aesthetics for interiors using artificial lighting techniques, especially during daytimes, and air conditioning due to increased thermal gains. This research intends to explore three basic types of dynamic facade systems, including folding, sliding and rotating types. The study is inclusive of the functional parameters, design and working mechanism of the selected systems, their impact on the illuminance and daylight factor, in the selected commercial building in Changanassery, Kerala, India. The authors calculated various angles of the selected location such as Solar Azimuth, Altitude, Horizontal Shadow Angle (HSA) and Vertical Shadow Angle (VSA), for further analysis. The tools used to do Building Information Modelling (BIM) of the prototype building, simulations of illuminance and daylight factor are Autodesk Revit, Autodesk Insight and Velux daylight visualizer respectively. The study concludes that the folding type of facade system is the most efficient type of dynamic facade system specific to the accurate prototype building location to ensure optimal daylighting while eliminating the undesirable effects of solar radiation.

A descriptive framework to evaluate instrument packages for the low-carbon transition

We develop a descriptive framework to facilitate policy instrument evaluation in relation to the low-carbon transition. The framework consists of a stock-taking and mapping analysis based on five questions. Four questions allow the policy maker to take stock of the existing set of instruments and provide a description of the key attributes and incentive of individual instruments. These attributes are subsequently mapped to identifiers of market failures related to the transition. A fifth question considers the coherence of the mix or package of policy instruments that the instruments constitute. The result is an overview of the incentives for firms and households to contribute to the transition towards a decarbonised economy. This can then be used to evaluate whether the set of policy instruments can be improved. We apply our framework to the residential and commercial (buildings) sector in an ambitious country, Austria.

The change in temporal trend and spatial distribution of CO2 emissions of China's public and commercial buildings

The CO2 emission mitigation of the commercial and public building sector (P&C) is critical for achieving China's carbon peak and carbon neutrality. Analyzing changes in CO2 emissions and their driving factors from temporal and spatial perspective provides insights for developing equitable and effective decarbonization strategies. This study investigated the change in temporal trend and spatial distribution of CO2 emissions of China's P&C during period of 2005–2018 according to the Kaya identify and Gravity Center model. Meanwhile, combined with the Logarithmic Mean Divisia Index, this study proposed a decomposed method to identify the driving factor of the movement of the gravity center. The results showed that: 1) in the temporal dimension, China's P&C has still not achieved its CO2 emissions peak, arriving 820.68 MtCO2. The most positive and negative driving factors were per capita add value of tertiary industry and energy efficiency, respectively; 2) in the spatial dimension, during the 13th Five Year Plan period, the gravity center moved southwestward, and the most positive and negative driving factors were energy consumption unit area and energy efficiency, respectively; Besides, to accelerate the decarbonization of China's P&C, this study reviewed the main decarbonization strategies, divided them into six categories and provided policy implications. In summary, this study provides a completed assessment on CO2 emission changes of China's P&C, facilitating policy-makers to develop more reasonable implementation plans for emission mitigation.

An assessment of the impact of passive design variations of the building envelope using thermal discomfort index and energy savings in warm and humid climate

Over the years, the commercial buildings sector has emerged as one of India’s fastest-growing sector and the commercial space is expected to grow four fold between 2015 and 2030. Due to the absence of thermal comfort regulations in India, designers frequently overdesign cooling systems in accordance with international norms, leading to unsustainable practises and energy wastage. The conventional building construction in India’s warm and humid climate make people uncomfortable due to heat gains, forcing the use of cooling equipment that require a lot of energy. Use of passive design options in the building envelope is thought to be a viable strategy for lowering energy usage. The different effects of building exterior components and passive design solutions on the indoor thermal environment can be effectively integrated using the criterion of thermal comfort. A new thermal discomfort index based on adaptive comfort using the numerical method and trapezoidal rule is established and used as a basis of comparison to assess the relative performance of building envelopes. In comparison to the reference building envelope in warm, humid climate, the research shows that careful attention to building envelope design with consideration of various passive options can improve the indoor thermal environment by 5.82 °C, reduce thermal discomfort by 80.75 percent and save energy up to 77 percent.

Optimal energy management of a solar-assisted heat pump water heating system with a storage system

Water heating is the fourth largest energy consumer in the commercial building sector, accounting for >40 % of the energy consumed in South Africa. Traditional electric storage tank water heaters (ESTWHs) have been the most frequently used systems in the past, owing to their low electricity costs and implementation. It was low enough at that time that energy costs were not considered. These systems have grown increasingly hostile to consumers as power prices have risen, particularly to the undesirable high morning and afternoon peaks.The indirect-expansion solar-assisted heat pump water heater (IDX-SAHPWH), for the commercial sector, to reduce energy consumption of hot water production while maintaining the users' thermal comfort level, has been proposed in this paper. The system is operated under an optimal energy control scheme, integrated with the load shifting by time-of-use (TOU) pricing plan. The comparison of the performance of the proposed optimally controlled system and the electric storage tank water heater (ESTWH) was performed through the simulation approach using the Solving Constraint Integer Programs (SCIP) solver, in the MATLAB interface optimization toolbox. The simulations reveal that the proposed system operates during off-peak hours, when power prices are lower, as compared to ESTWH system.The techno-economic analysis was conducted and presented for a project lifespan of 20 years. The proposed optimally controlled system demonstrates the cost savings obtained from the winter and summer seasons, as well as annual, as 76.0 %, 75.6 % and 75.8 %, respectively. The break-even point of the project is during the 9th month of the first year of the project, with a possible savings of 71.5 % at the end of the project's lifetime.

China’s commercial building carbon emissions toward 2060: An integrated dynamic emission assessment model

Carbon-mitigation in the commercial building sector is critical to carbon peaking and carbon neutral commitment. However, there has been little scientific focus on long-term evolutionary trajectories and peak path in this sector. This study innovatively develops an integrated dynamic emission assessment model (IDEAM) by combining the system dynamics model with the bottom-up end-use energy model. Moreover, the IDEAM is combined with the scenario analysis approach to model the dynamic evolution of Chinese commercial building carbon emissions toward 2060. The results show that commercial building carbon emissions will peak at 1.28 Gigatons (Gt) of CO2 in 2037 under the baseline scenario and will advance toward 2029 with an emissions peak of 0.98 Gt CO2 under the low-carbon scenario. Cooling and lighting are the two end-uses that contribute most to the growth of carbon emissions at over 70%. These two end-uses indicate different carbon-abatement potentials across climate zones. Sensitivity analysis reveals that promoting technological progress, increasing the share of clean energy, and improving low-carbon awareness are major ways to facilitate the early realization of carbon peaks and carbon neutrality. This study provides a deeper understanding of possible emission pathways and could assist policy-makers in devising scientific carbon mitigation plans.

Risk allocation for energy performance contract from the perspective of incomplete contract: a study of commercial buildings in China

PurposeThis article aims to establish a dynamic Energy Performance Contract (EPC) risk allocation model for commercial buildings based on the theory of Incomplete Contract. The purpose is to fill the policy vacuum and allow stakeholders to manage risks in energy conservation management by EPCs to better adapt to climate change in the building sector.Design/methodology/approachThe article chooses a qualitative research approach to depict the whole risk allocation picture of EPC projects and establish a dynamic EPC risk allocation model for commercial buildings in China. It starts with a comprehensive literature review on risks of EPCs. By modifying the theory of Incomplete Contract and adopting the so-called bow-tie model, a theoretical EPC risk allocation model is developed and verified by interview results. By discussing its application in the commercial building sector in China, an operational EPC three-stage risk allocation model is developed.FindingsThis study points out the contract incompleteness of the risk allocation for EPC projects and offered an operational method to guide practice. The reasonable risk allocation between building owners and Energy Service Companies can realize their bilateral targets on commercial building energy-saving benefits, which makes EPC more attractive for energy conservation.Originality/valueExisting research focused mainly on static risk allocation. Less research was directed to the phased and dynamic risk allocation. This study developed a theoretical three-stage EPC risk allocation model, which provided the theoretical support for dynamic EPC risk allocation of EPC projects. By addressing the contract incompleteness of the risk allocation, an operational method is developed. This is a new approach to allocate risks for EPC projects in a dynamic and staged way.

Trends, benefits, risks, and challenges of IoT implementation in residential and commercial buildings

• A review of IoT approaches in residential and commercial buildings is provided. • Trends of the current literature are presented. • Advantages of IoT implementation in built environments are discussed. • Future research lines are provided. Residential and commercial buildings are undergoing a dramatic change, and the Internet of Things (IoT) technologies are shaping the future of these buildings. Researchers have recently utilized IoT in a variety of applications and settings to transfer conventional buildings into smart, efficient, and secure buildings. While functional IoT approaches have been developed, there is still a need for improvement in IoT applications and operations to understand the full potential of this technology. This improvement can properly be done by bridging the gaps of the current literature to provide a building block for future studies. The objective of this paper is to present a comprehensive review of research work on the existing technologies and applications of IoT in residential and commercial buildings. For residential buildings, studies are divided to three major categories of home automation, intelligent energy management systems, and healthcare facilities. For commercial buildings, the current literature is divided to four categories of office buildings, healthcare facilities, educational buildings, and restaurants and retail facilities. Based on the review of each category, the trends, current benefits and risks, and future challenges of the IoT implementation in the built environments are identified and discussed. In particular, integration of various IoT technologies with different capabilities, data storage and processing, and privacy and security risks are identified as the main challenges for IoT implementation. In addition, our results show that the commercial building sector has received more attention compared to the residential building sector. By providing the directions for future research opportunities, this paper benefits IoT developers and researchers to properly identify their work boundaries and define their contributions.

Net-zero energy management and optimization of commercial building sectors with hybrid renewable energy systems integrated with energy storage of pumped hydro and hydrogen taxis

This study develops net-zero energy management and optimization approaches for the commercial building sector in cities powered by renewable energy systems integrated with energy storage of pumped hydro and hydrogen taxis, based on the estimated installation potential of solar photovoltaics and offshore wind power. A novel time-of-use energy management strategy of hybrid renewable energy and storage systems is proposed considering the future-oriented application scenario with high renewable energy generation and shifted peak power periods. Multi-objective optimizations are conducted to find the techno-economic-environmental optimum sizing configurations of the pumped hydro storage. Research results indicate that most of Pareto optimal solutions are achieved with large pumped hydro sizes applied in net-zero energy commercial building sectors. The proposed future-oriented time-of-use strategy significantly improves the system supply and economic performance, in terms of the renewable energy self-consumption (+9.24%), load coverage (+6.10%) and annual electricity bill (-25.21%) compared with the current time-of-use case. Obvious decarbonisation benefits of the renewable power supply and renewable hydrogen mobility are achieved with carbon emission reduction of 95.14% (14713.49 M kg CO2) compared with the traditional grid power supply and 80.74% (293.91 M kg CO2) compared with the traditional petroleum taxis under the future-oriented time-of-use strategy. The proposed net-zero energy planning framework for urban building sectors integrating decarbonized transportation can be applied in similar coastline cities in the globe as important references and guidelines to policymakers for achieving carbon neutrality by 2050.

Challenges and Efforts toward Decarbonization in the Residential and Commercial Building Sectors

Challenges and Efforts toward Decarbonization in the Residential and Commercial Building Sectors

Operational Carbon Change in Commercial Buildings under the Carbon Neutral Goal: A LASSO–WOA Approach

The rapid growth of energy consumption in commercial building operations has hindered the pace of carbon emission reduction in the building sector in China. This study used historical data to model the carbon emissions of commercial building operations, the LASSO regression was applied to estimate the model results, and the whale optimization algorithm was used to optimize the nonlinear parameter. The key findings show the following: (1) The major driving forces of carbon emissions from commercial buildings in China were found to be the population size and energy intensity of carbon emissions, and their elastic coefficients were 0.6346 and 0.2487, respectively. (2) The peak emissions of the commercial building sector were 1264.81 MtCO2, and the peak year was estimated to be 2030. Overall, this study analyzed the historical emission reduction levels and prospective peaks of carbon emissions from China’s commercial buildings from a new perspective. The research results are helpful for governments and decision makers to formulate effective emission reduction policies and can also provide references for the low-carbon development of other countries and regions.