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Heating, ventilating, air-conditioning and cooling (HVAC) systems are crucial in daily health-care facility services. Design-related defects can lead to maintenance issues, causing service disruptions and cost overruns. These defects can be avoided if a link between the early design stages and maintenance feedback is established. This study aims to use experts’ experience in HVAC maintenance in health-care facilities to list and evaluate the risk of each maintenance issue caused by a design defect, supported by the literature.

Following semistructured interviews with experts, 41 maintenance issues were identified as the most encountered issues. Subsequently, a survey was conducted in which 44 participants evaluated the probability and impact of each design-caused issue.

Chillers were identified as the HVAC components most prone to design defects and cost impact. However, air distribution ducts and air handling units are the most critical HVAC components for maintaining healthy conditions inside health-care facilities.

The unavailability of comprehensive data on the cost impacts of all design-related defects from multiple health-care facilities limits the ability of HVAC designers to furnish case studies and quantitative approaches.

This study helps HVAC designers acquire prior knowledge of decisions that may have led to unnecessary and avoidable maintenance. These design-related maintenance issues may cause unfavorable health and cost consequences.

It is important to provide building performance feedback to the designer as early as possible in the design process. However, many aspects of building performance are significantly affected by the design of the building’s technical systems (e.g., heating, airconditioning), which are typically configured in detail only in the later stages of design. The challenge is thus to find a method to use detailed simulation tools even during the early stages of design when values for many of the variables for the building’s technical systems are not yet available. In this paper, we demonstrate how this problem can be partially solved by use of differential representation for building and technical system, homology‐based automatic mapping of relevant information from the building to the technical system representation, and generative design agents which, with a minimal user‐input, can design and model the technical system. We conclude the paper with illustrative examples of detailed performance analysis of complex buildings and their heating, ventilation, and air‐conditioning systems, performed in early stages of design.

A framework for the successful implementation of energy retrofit projects in all settings, including those found within some non-profit organizations, is proposed. Strategies for overcoming common challenges along with experiences gained through a real-life case study of a multi-facility retrofit project were researched. The paper aims to discuss these issues.

This research incorporates strategies identified in existing literature with a variety of techniques and includes information from a detailed case study involving the retrofit of multiple buildings within a public park. Combined research strategies and real-life experience through the case study are used to develop a framework for recommended framework to analyze the completion of retrofit projects.

Common obstacles encountered by energy retrofit projects in the USA and Europe were identified. The retrofit case also experienced these challenges in varying degrees. Application of these practices was implemented and applied to each specific situation within the project and documented for analysis.

Current research tends to be focused on the implementation of energy efficient solutions as justified by a quick rate of return and long term savings. However, few projects in not-for-profit situations where a grant or donation is the funding source, and ROI is not measured from a traditional financial standpoint, have been researched.

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.

The purpose of this paper is to inform information and communication design for multi‐disciplinary multi‐national projects through the presentation of examples and recommendations based on lessons learned.

Experiences from action research involving field study with 20 organizations, together with survey research involving 30 external experts.

Shared understanding in multi‐disciplinary multi‐national projects can be better enabled through the application of information and communication design.

The action research involved only two cases.

Project participants need to have shared understandings in order to achieve project objectives. There are formidable inherent barriers to shared understanding in multi‐disciplinary multi‐national projects. Generic methods for the communication of information; such as use of gestures, speaking business English, and application of standard process charting; can be ineffective. Particularly, when inherent challenges are exacerbated by the introduction of new technological and/or business concepts. Information design seeks to improve the effectiveness of information. Communication design is concerned with the selection of media most suitable for carrying particular information to specific audiences/recipients.

The originality of the research reported in this paper is that it encompasses: inherent challenges in establishing shared understanding; limitations of generic methods for the communication of information; issues underlying information and communication design; as well as two cases of multi‐disciplinary multi‐national projects. The value of this paper is that it includes practical examples to inform information and communication design by personnel in project businesses. Further, practical recommendations for reducing time and cost are provided. Furthermore, these practical recommendations are related to the challenges highlighted by established theory.

Heating, ventilation and air-conditioning (HVAC) systems account for approximately half of all energy usage in the operational phase of a building's lifecycle. The disproportionate amount of energy usage in HVAC systems against other utilities within buildings has proved a huge cause for alarm, as this practice contributes significantly to global warming and climate change. This paper reviews the status and current trends of energy consumption associated with HVAC systems with the aim of interrogating energy efficiency practices for improving HVAC systems' consumption in buildings in the context of developing countries.

The study relied predominantly on secondary data by analysing the relevant body of literature and proposing conceptual insights regarding best practices for improving the energy efficiency of HVAC systems in buildings. The systematic review of the literature (SLR) was aided by the PRISMA guiding principle. Content analysis technique was adopted to examine germane scholarly articles and finally grouped them into themes.

Based on the SLR, measures for enhancing the energy efficiency of HVAC systems in buildings were classified based on economic considerations ranging from low-cost measures such as the cost of tuning the system, installing zonal control systems, adopting building integrated greenery systems and passive solar designs to major approaches such as HVAC smart technologies for energy management which have multi-year pay-back periods. Further, it was established that practices to improve energy efficiency in buildings range from integrated greening system into buildings to HVAC system which are human-centred and controlled to meet human modalities.

There is a need to incorporate these energy efficiency practices into building regulations or codes so that built environment professionals would have a framework within which to design their buildings to be energy efficient. This energy efficient solution may serve as a prerequisite for newly constructed buildings.

To this end, the authors develop an integrated optimization conceptual framework mimicking energy efficiency options that may complement HVAC systems operations in buildings.

The history of commercial CFD software began when CHAM launched the first version of PHOENICS in 1981. Others followed, but PHOENICS has retained its status as the original and best validated CFD code.

The purpose of this research is to design a robust high-performance nonlinear multi-input multi-output heating, ventilation and air conditioning (HVAC) system controller for temperature and relative humidity regulation. Buildings are complex systems which are subjected to many unknown disturbances. Further complicating the control problem is the fact that, in practice, buildings and their systems have static nonlinearities such as power saturation that make stability difficult to guarantee. Therefore, in order to overcome these issues, a control system must be designed to be robust (performance insensitive) against uncertainties, static nonlinearities and effectively respond to unknown heat load and moisture disturbances.

A state of the art nonlinear inverse dynamics (NID) technique is combined with a genetic algorithm (GA) optimisation scheme in order to improve robustness against uncertainty in the system's modelling assumptions. The parameter uncertainty problem is addressed by optimising the control system parameters over a specified range of uncertainty. The NID control structure provides further robustness with effective disturbance handling and a stability criteria that holds in the presence of actuator saturation.

The proposed method delivers significantly more energy efficient performance whilst achieving improved thermal comfort when compared with a current industry standard HVAC controller design such as proportional-integral-derivative. The expected excellent response to disturbances is also demonstrated.

This method can easily be extended to account for other parameters with a specified uncertainty range.

This research presents a method of optimised NID controller design which can be easily implemented in real HVAC controllers of building energy management systems with a high degree of confidence to provide high levels of thermal comfort whilst significantly reducing energy usage.

A novel HVAC optimised NID control strategy using the robust inverse dynamics estimation feedback control topology with GA optimisation for improved robustness and tuning over a range of parameter uncertainty is described, designed and its performance benefits shown through simulation studies.

The two main contributing factors that control the overall buildings’ energy performance are the heating ventilation and air conditioning (HVAC) system and the envelope design. Environmental design guidelines that consider these two factors aim to lower energy consumption. However, they are regional and climate-sensitive. This study aims to investigate how three main buildings’ envelope design variables (orientation, compactness and window to wall ratio) impact the overall building’s energy consumption within Kuwait’s regional and climate conditions.

This study simulate the energy consumption of typically shaped buildings by varying their geometry between a square to a rectangular floor plan. This study analyse the associated energy usage and provide early-stage envelope design guidance specific to the country’s conditions, to make informed decisions towards environmentally conscious buildings.

The analysed envelope variables have the potential to reduce energy consumption by 40%, and the possibility to reduce HVAC system capacity by 30%. In contrast to the general guidance in literature and standards, the simulation results demonstrate that less compact building forms perform on occasions better than the most compact ones.

The objective of this paper is to quantify the energy consumption rates for buildings located within the Arabian Peninsula, an under-studied region with potentially high interest considering three main envelope design variables. The buildings’ yearly energy consumption patterns are unique and suggest different envelope design considerations, compared to other regions with different climate conditions. This emphasises the importance of regional guidelines for the different factors associated with energy and buildings’ environmental performance.