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Design teams have difficulties in assessing building carbon emissions at an early stage, as most building energy simulation tools require a detailed input of building design for estimation. The purpose of this paper is to develop a user-friendly regression model to estimate carbon emissions of the preliminary design of office buildings in the subtropics by way of example. Five sets of building design parameters, including building configuration, building envelope, design space conditions, building system configuration and occupant behaviour, are considered in this study.

Both EnergyPlus and Monte Carlo simulation were used to predict carbon emissions for different combinations of the design parameters. A total of 100,000 simulations were conducted to ensure a full range of simulation results. Based on the simulation results, a regression model was developed to estimate carbon emissions of office buildings based on preliminary design information.

The results show that occupant density, annual mean occupancy rate, equipment load, lighting load and chiller coefficient of performance are the top five influential parameters affecting building carbon emissions under the subtropics. Besides, the design parameters of ten office buildings were input into this user-friendly regression model for validation. The results show that the ranking of its simulated carbon emissions for these ten buildings is consistent with the original carbon emissions ranking.

With the use of this developed regression model, design teams can not only have a simple and quick estimation of carbon emissions based on the building design information at the conceptual stage but also explore design options by understanding the level of reduction in carbon emissions if a certain building design parameter is changed. The study also provides recommendations on building design to reduce carbon emissions of office buildings.

Limited research has been conducted to date to investigate how the change of building design affects carbon emissions in the subtropics where four distinct seasons lead to significant variations of outdoor temperature and relative humidity. Previous research also did not emphasise on the impact of high-rise office building designs (e.g. small building footprint, high window-to-wall ratio) on carbon emissions. This paper adds value by identifying the influential parameters affecting carbon emissions for a high-rise office building design and allows a handy estimate of building carbon emissions under the subtropical conditions. The same approach may be used for other meteorological conditions.

This study aims to apply association rule mining (ARM) to uncover specific associations between operating components of a chiller system and improve its coefficient of performance (COP), hence reducing the electricity use of buildings with central air conditioning.

First, 13 operating variables were identified, comprising measures of temperatures and flow rates of system components and their switching statuses. The variables were grouped into four bins before carrying out ARM. Strong rules were produced to associate the variables and switching statuses with different COP classes.

The strong rules explain existing constraints on practising chiller sequencing and prioritise variables for optimisation. Based on strong rules for the highest COP class, the optimal operating strategy involves rescheduling chillers and their associated components in pairs during a high load operation. Resetting the chilled water supply temperature is the next best strategy, followed by resetting the condenser water entering temperature, subject to operating constraints.

This study considers the even frequency method with four bins only. Replication work can be done with other discretisation methods and different numbers of classes to compare potential differences in the bin ranges of the optimised variables.

The strong rules identified by ARM highlight associations between variables and high or low COPs. This supports the selection of critical variables and the operating status of system components to maximise the COP. Tailor-made optimisation strategies and the associated electricity savings can be further evaluated.

Previous studies applied ARM for chiller fault detection but without considering system performance under the interaction of different components. The novelty of this study is its demonstration of ARM’s intelligence at discovering associations in past operating data. This enables the identification of tailor-made energy management opportunities, which are essential for all engineering systems. ARM is free from the prediction errors of typical regression and black-box models.

In many countries, innovation in building design for improving energy performance, reducing CO2 emissions and minimizing life cycle cost has received much attention for sustainable development. This paper investigates the importance of optimization tools for enhancing the design performance in the early stages of Vietnam's cooling-dominated buildings in hot and humid climates using an integrated building design approach.

The methodology of this study exploits the non-dominated sorting genetic algorithm (NSGA-II) optimization algorithm coupled with building simulation to research a trade-off between the optimization of investment cost and energy consumption. Our approach focuses on the whole optimization problem of thermal envelope, glazing and energy systems from preliminary design phases. The methodology is then tested for a case study of a non-residential building located in Hanoi.

The results show a considerable improvement in design performance by our method compared to current building design. The optimal solutions present the trade-off between energy consumption and capital cost in the form of a Pareto front. This helps architects, engineers and investors make important decisions in the early design stages with a large view of impacts of all factors on energy performance and cost.

This is one of the original research to study integrated building design applying the simulation-based genetic optimization algorithm for cooling-dominated buildings in Vietnam. The case study in this article is for a non-residential building in the north of Vietnam but the methodology can also be applied to residential buildings and other regions.

The operation of chiller systems could account for considerable electricity consumption in air‐conditioned buildings in subtropical regions. The purpose of this paper is to consider using data envelopment analysis (DEA) to facilitate management of their energy performance.

A system serving an institutional building was studied, which contains five sets of chillers, pumps and cooling towers. The building has a total floor area of about 25,000m² and comprises classrooms, lecture theatres, offices and laboratories. The scale, technical and overall efficiencies defined in DEA were calculated based on the correlation between the output variable – system coefficient of performance (COP) – and the input variables – load factor and temperatures of chilled water and condenser water. The efficiencies were further examined to explain how outside air temperatures and controllable variables affect the system performance.

The paper reveals that existing energy management gives a technical efficiency of 0.85 and fine‐tuning the temperature‐related variables could achieve an electricity saving of 14.8 per cent.

The improved COP predicted by DEA is related only to fine‐tuning of the input variables concerned. An increase of COP by other advanced controls or system upgrades should be assessed based on robust system modelling techniques. Yet the extent of COP improvements helps investigate energy management opportunities requiring no or insignificant capital investment on existing systems.

A systematic approach to performing energy management of a chiller system is proposed. The DEA helps examine which operating variable should be fine‐tuned to achieve the highest possible performance.

It is an under researched area to consider using scale and technical efficiencies in DEA to explain energy management of chiller systems and to estimate the highest achievable performance.

This article discusses the basics of computer‐room air conditioning, an important component of the special environment required by mainframe computers and many mini‐computers as well. Computer room air conditioners differ in some significant ways from “comfort” air‐conditioners, which are designed for the comfort of people rather than machines. These differences make it less than ideal to use air conditioning systems designed for human comfort for computer cooling. The author describes several different types of air‐conditioners, considerations related to the construction of a computer room, and factors that determine air‐conditioning requirements.

Post-graduation.

Strategic Management and Entrepreneurship.

By July 2021, the curve of COVID-19 second wave started flattening. Hetika Shah, the founder of Sanctuary Innovative Safety Equipment, was unsure whether her business would survive in the long run. The company manufactured 4S Shield N99 masks. The business was doing well when the COVID curve was at its peak; however, the sales wobbled with the flattening of the curve. As the company had manufactured the product, especially for doctors who need protection from COVID, the demand showed a sudden fall after the second wave. She was certain that the business would not survive only on 4S shield mask. Diversification of this business seemed to be a suitable idea, where she could manufacture other safety equipment for the manufacturing industry. At that time, she had neither done market research nor had any prototype for such equipment. This variety of products required a huge investment of funds and time. But, as per the market demand of the existing product, it was crucial to make quick decisions for business survival. She had options in front of her, but the uncertainty of the market deterred the decision-making. She was at a junction with three possible choices: One option was to stay in the business of masks and expand it in medical devices market under health-care industry. The masks could be used by doctors engaged in the treatment of other diseases. She planned to distribute masks to doctors treating tuberculosis and cancer. Another option was to shift her attention to diversification of the business and enter the market of safety equipment under manufacturing industry that demanded more investment and a lot of market research. The main idea was to come up with innovative safety equipment. Though, this opportunity came with its array of risks. The last option was to shift towards her underdeveloped chiller prototype for industrial use. By that time, the prototype was 75% complete. Still, it required a lot more time and attention to be brought at the commercializing stage.

The case study can be used in the Entrepreneurship and Strategic Management course. It would be suitable for students at the post-graduation level. Discussion would be on the appropriate teaching method. Though there is no prerequisite, it would be better if students had a basic understanding of entrepreneurship and strategic management. It discusses the entrepreneurial dilemma of starting a business. Furthermore, the case explains the decision dilemma of the entrepreneur about the continuance of existing business, expansion and diversification. Students will be able to understand the following concepts: business plan, business development, strategic decision-making in business, entrepreneurial opportunities, sustainability of an enterprise and challenges faced by entrepreneurs. After this case study, students will be able to understand the following models and theories: uncertainty-bearing theory of entrepreneurship, porter’s generic strategy, porter’s five competitive forces, strengths, weaknesses, opportunities, and threats (SWOT) analysis, scenario planning, Ansoff’s growth model and social role theory.

Teaching Notes are available for educators only.

Women entrepreneurship.

CSS 3: Entrepreneurship.

Energy management in existing building services installations is an essential focus of contemporary facilities management. The subway company that is one of the major utilities services in Hong Kong Special Administrative Region has considered better energy management schemes in its subway stations to reduce the running cost. In the past few years some feasible measures in the mechanical ventilation and air conditioning (MVAC) systems were implemented, however the engineering decisions were supported by trial‐and‐error or imprecise estimation. Improvement to this process would be possible if numerical optimization methods were to be used. An evolutionary algorithm coupled with an external plant simulation programme was applied to determine the optimum conditions of the essential parameters of the MVAC systems. For the centralized MVAC systems under study, the developed optimization and simulation model was found useful in appraising the energy management opportunities for effective design and facilities management.

This paper aims to investigate how unique features of built facilities would affect the application of greenhouse gas (GHG) emissions trading, and to explore what adaptive measures may be taken for emissions trading to be applied to the built environment. Emissions trading is a financial tool to encourage GHG emissions reduction in various industries. As the building sector is responsible for a large amount of GHG emissions, it is valuable to explore the application of emissions trading in built facilities.

The analysis is based on a comparative study reviewing the current emissions trading schemes (ETSs) in Australia, Japan and the UK covering the building industry, and to evaluate the approaches adopted by the schemes to tackle the problems related to buildings and facilities management.

The research findings reveal that the small energy savings of individual building units, the large variety of energy-saving technologies and the split incentives and diverse interests of building owners and tenants would be the barriers hindering the development of emissions trading. To overcome these barriers, an ETS should allow its participants to group individual energy savings, lower the complexity of monitoring and reporting approaches and allow owners and tenants to benefit from emissions trading.

This article provides a comprehensive overview of the current emissions trading practices in the built environment. Besides, it raises the attention and consciousness of policymakers to the need that building characteristics and facilities management should be taken into consideration when designing an ETS for the building sector.

The purpose of this paper is to investigate the current market development of Energy Performance Contracting (EnPC) in Hong Kong and Taiwan, focussing on four key aspects: first, the potential building energy retrofits as an investment for future savings; second, the motivations for building owners toward the use of EnPC; third, the reasons for building owners not using EnPC; and fourth, the different approaches of Hong Kong and Taiwanese governments toward the promotion of EnPC.

A dual-questionnaire survey was conducted both in Hong Kong and Taiwan, where the same set of questionnaire was sent to the key personnel of the energy services companies (ESCOs) in both regions as identified from the latest member lists of representative trade associations, supplement with 11 structured interviews.

Apart from explainable differences, the results show the top rankings by the respondents of Hong Kong and Taiwan as follows: “Potential retrofit works” including lighting replacement with efficient fluorescent and light emitting diode lamps and improvement of air-con system. “EnPC Motivations” including owners’ lack of upfront capital and use of energy savings for other purposes may yield better returns; ESCOs’ provision of turnkey services. “Reasons not considering EnPC” including worry about its complexities; lack of familiarity with EnPC and long payback periods. As for promotional efforts for EnPC, the Taiwan government has taken more initiatives to foster its use both technically and financially.

This study identifies market-related motivators and deterrents as experienced by ESCOs in implementing EnPC projects in two developed Asian economies.

This study provides insightful information for the stakeholders about the latest market development of EnPC in Hong Kong and Taiwan.

This paper aims to focus on the decision-making process of integrated system design. Buildings can benefit from different system integration working toward the unified goal of providing the needed conditions and improving the comfort level of occupants. It is important to engage all system needs and priorities in the design by keeping goal into consideration. Even though there is vast potential in the coordination of system design decisions, there is a need to increase the transparency of the decision-making process by developing methods to incorporate multi-dimensional design attributes.

This is achieved by considering all system design priorities with respect to decision attributes, as well as the inter-system inputs based on information and knowledge. Data were collected through interviews, collaboration meetings and design document reviews, which helped to facilitate triangulation.

This paper presents the findings of a case study of deep retrofit design process that seeks to reduce energy consumption through integrated system decisions with several system combinations. In addition, such design decisions highlighted the fact that the values need to be flexible at the system level.

This paper presents an in-depth analysis of a single case study. Multiple case studies are being investigated for the future of this research.

This paper presents the methods used for integrated design process priorities that will enable design teams to make decisions that lead to improved energy performance in retrofit projects.

The case study building in this paper is a showcase building with cutting edge technologies and techniques, as well as a scalable and collaborative design process. It is an example of a best-in-class retrofit process designed through whole building design principles within the target budget. The paper demonstrates system design selection criteria that are embraced by value prioritization.