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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.

Organizations involved in facility management (FM) can use building information modeling (BIM) as a knowledge repository to document evolving facility information and to support decisions made by the facility managers during the operational life of a facility. Despite ongoing advances in FM technologies, FM practices in most facilities are still labor intensive, time consuming and often rely on unreliable and outdated information. To address these shortcomings, the purpose of this study is to propose an automated approach that demonstrates the potential of using BIM to develop algorithms that automate decision-making for FM applications.

A BIM plug-in tool is developed that uses a fault detection and diagnostics (FDD) algorithm to automate the process of detecting malfunctioning heating, ventilation, and air conditioning (HVAC) equipment. The algorithm connects to a complaint ticket database and automates BIM to determine potentially damaged HVAC system components and develops a plan of action for the facility inspectors accordingly. The approach has been implemented as a case study in an operating facility to improve the process of HVAC system diagnosis and repair.

By implementing the proposed application in a case study, the authors found that automated BIM approaches such as the one developed in this study, can be highly beneficial in FM practices by increasing productivity and lowering costs associated with decision-making.

This study introduces an innovative approach that leverages BIM for automated fault detection in operational buildings. FM personnel in charge of HVAC inspection and repair can highly benefit from the proposed approach, as it eliminates the time required to locate HVAC equipment at fault manually.

The purpose of this study was to examine how data from the World Health Organization, United States Environmental Protection Agency and Center for Disease Control have evolved with relation to engineering controls for heating, ventilation and air-conditioning (HVAC) systems to mitigate the spread of spread of aerosols (specifically related to the COVID-19 pandemic) in occupied buildings.

A document analysis of the pandemic-focused position documents from the aforementioned public health agencies and national HVAC authorities was performed. This review targeted a range of evidence from recommendations, best practices, codes and regulations and peer-reviewed publications and evaluated how they cumulatively evolved over time. Data was compared between 2020 and 2021.

This research found that core information provided early in the pandemic (i.e. early 2020) for engineering controls in building HVAC systems did not vary greatly as knowledge of the pandemic evolved (i.e. in June of 2021). This indicates that regulating agencies had a good, early understanding of how airborne viruses spread through building ventilation systems. The largest evolution in knowledge came from the broader acceptance of building ventilation as a transmission route and the increase in publications and ease of access to the information for the general public over time.

The promotion of the proposed controls for ventilation in buildings, as outlined in this paper, is another step toward reducing the spread of COVID-19 and future aerosol spread viruses by means of ventilation.

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.

Despite discussions about the universal work station, there is increasing workplace dynamics in US organisations. These dynamics include space configuration changes, space enclosure changes, changes in occupant density and increasing equipment density. At the same time, building infrastructures have not evolved to meet these demands, with little flexibility in the heating, ventilation and air‐conditioning (HVAC), lighting, or electrical/telecommunication systems of new or existing office buildings. This paper examines the effects of organisational workplace dynamics and building infrastructure flexibility on the environmental and technical quality of offices. Resulting from extensive field studies in US buildings, the authors contend that there are numerous statistically significant issues for the design and management of buildings for the dynamic organisation. The study identified numerous factors that affect thermal, air, lighting and technical quality in offices. In relation to infrastructure, for example, occupants who work in office areas provided with greater cooling capacity and more supply air volume, and combined with smaller HVAC zones, appeared to have higher levels of thermal satisfaction. Those who work in areas with higher outlet densities gave higher technical quality ratings; and those provided with relocatable outlets (raised floor and furniture based) gave significantly higher technical satisfaction ratings than those provided with least‐first‐cost ‘tombstones’. In relation to organisational dynamics, increasing occupant densities in existing buildings are related to more thermal and air quality complaints, more complaints about outlet accessibility, as well as more complaints about inadequate light levels on work surfaces. This paper will outline the major findings of a study linking organisational dynamics with building infrastructure, moving towards the definition of innovations in facility design that will more effectively support dynamic organisations.

The purpose of this study is to obtain the optimal frequency for low-frequency transmission lines while minimizing losses and maintaining the voltage stability of low-frequency systems. This study also emphasizes a reduction in calculations based on mathematical approaches.

Telegrapher’s method has been used to reduce large calculations in low-frequency high-voltage alternating current (LF-HVac) lines. The static compensator (STATCOM) has been used to maintain voltage stability. For optimal frequency selection, a modified Jaya algorithm (MJAYA) for optimal load flow analysis was implemented.

The MJAYA algorithm performed better than other conventional algorithms and determined the optimum frequency selection while minimizing losses. Voltage stability was also achieved with the proposed optimal load flow (OLF), and statistical analysis showed that the proposed OLF reduces the frequency deviation and standard error of the LF-HVac lines.

The optimal frequency for LF-HVac lines has been achieved, Telegrapher’s method has been used in OLF, and STATCOM has been used in LF-HVac transmission lines.

The purpose of this study is to conduct a rigorous systematic literature review and present a summary of building systems and technologies that can be used to mitigate the spread of airborne viruses. With the recent outbreak of COVID-19, occupants’ health and indoor air quality (IAQ) have become a critical issue for facility managers to maintain the full functionality of the buildings. An improved understanding of these available systems will help facility managers and building owners to protect the health and safety of building occupants.

The PRISMA protocol was used for defining the literature search methodology. The concept mapping technique was used for determining the keywords. The keywords were then used to search for relevant articles using the Scopus database and Google Scholar. A thorough bibliometric analysis and qualitative analysis were conducted for the selected publications.

It was found that sensor technologies, botanical air-filtration systems and artificial intelligence could be used to effectively monitor and improve IAQ. In addition, natural ventilation is one of the low-cost and effective methods of reducing contaminants from the indoor air. Computational fluid dynamic modeling can be used to understand the flow of virus particles within the building through the heating, ventilation and air-conditioning (HVAC) system. Several changes to the HVAC system are also discussed.

This study contains a diversity of methods from the existing literature that were systematically selected to present the state-of-the-art building systems and technologies that can effectively improve IAQ. The researchers plan to follow up on the findings of this research and will conduct an empirical study to assess its impact on IAQ.

The calculation of buildings’ carbon footprint (CFP) is an important basis for formulating energy-saving and emission-reduction plans for building. As an important building type, there is currently no model that considers the time factor to accurately calculate the CFP of hospital building throughout their life cycle. This paper aims to establish a CFP calculation model that covers the life cycle of hospital building and considers time factor.

On the basis of field and literature research, the basic framework is built using dynamic life cycle assessment (DLCA), and the gray prediction model is used to predict the future value. Finally, a CFP model covering the whole life cycle has been constructed and applied to a hospital building in China.

The results applied to the case show that the CO₂ emission in the operation stage of the hospital building is much higher than that in other stages, and the total CO₂ emission in the dynamic and static analysis operation stage accounts for 83.66% and 79.03%, respectively; the difference of annual average emission of CO₂ reached 28.33%. The research results show that DLCA is more accurate than traditional static life cycle assessment (LCA) when measuring long-term objects such as carbon emissions in the whole life cycle of hospital building.

This research established a carbon emission calculation model that covers the life cycle of hospital building and considered time factor, which enriches the research on carbon emission of hospital building, a special and extensive public building, and dynamically quantifies the resource consumption of hospital building in the life cycle. This paper provided a certain reference for the green design, energy saving, emission reduction and efficient use of hospital building, obviously, the limitation is that this model is only applicable to hospital building.

The issue of energy efficiency is becoming increasingly prevalent globally due to factors such as the expansion of the population, economic growth and excessive consumption that is not sustainable in the long run. Additionally, healthcare facilities and hospitals are facing challenges as their operational costs continue to rise. The research aim is to develop strategic frameworks for managing green hospitals, towards energy efficiency and corporate governance in hospitals and healthcare facilities.

This research employs a qualitative case study approach, with a sample of ten hospitals examined through interviews with senior management, executives and healthcare facilities managers. Relevant data was also collected from literature and analysed through critical appraisal and content analysis. The research methodology is based on the use of grounded theory research methodologies to build theories from case studies.

The research developed three integrated conceptual strategic frameworks for managing hospitals and healthcare facilities towards energy efficiency, green hospital initiatives and corporate governance. The research also outlined the concepts of green hospitals and energy efficiency management systems and best practices based on the conclusions drawn from the investigated case studies.

The study is limited to the initiatives and experiences of the healthcare facilities studied in the Middle East and North Africa (MENA) region.

The research findings, conclusions, recommendations and proposed frameworks and concepts contribute significantly to the existing body of knowledge. This research also provides recommendations for hospital managers and policymakers on how to effectively implement and manage energy efficiency initiatives in healthcare facilities.

The residential buildings sector has a high priority in the climate change adaptation process due to significant CO₂ emissions, high energy consumption and negative environmental impacts. The article investigates how, conversely speaking, the residential buildings will be affected by climate change, and how to improve existing structures and support long-term decisions.

The climate dataset was created using the scenarios determined by the Intergovernmental Panel on Climate Change (IPCC), and this was used in the study. Different building envelope and Heating, Ventilating and Air Conditioning (HVAC) systems scenarios have been developed and simulated. Then, the best scenario was determined with comparative results, and recommendations were developed.

The findings reveal that future temperature-increase will significantly impact buildings' cooling and heating energy use. As the outdoor air temperatures increase due to climate change, the heating loads of the buildings decrease, and the cooling loads increase significantly. While the heating energy consumption of the house was calculated at 170.85 kWh/m² in 2020, this value shall decrease significantly to 115.01 kWh/m² in 2080. On the other hand, the cooling energy doubled between 2020 and 2080 and reached 106.95 kWh/m² from 53.14 kWh/m² measured in 2020.

Single-family houses constitute a significant proportion of the building stock. An in-depth analysis of such a building type is necessary to cope with the devastating consequences of climate change. The study developed and scrutinised energy performance improvement scenarios to define the climate change adaptation process' impact and proper procedure. The study is trying to create a strategy to increase the climate resistance capabilities of buildings and fill the gaps in this regard.