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The purpose of this paper is to provide a new mentality of constructing the evaluation index system on national energy security, in favor of analyzing its influencing factors and coupling relations thoroughly.

The complex adaptive system (CAS) theory has provided one kind analysis method on modeling and simulation for question of the social economic system, which based on the adaptive agent and mutual interaction. In view of this, the authors' expect to use this kind of new research paradigm for reference, and construct the evaluation index systems on national energy security using the integration of CAS theory and pressure‐state‐response (PSR) conceptual model.

Constructs a set of compound index system of “six parallel layers, gradually converge, six layers three dimensions three degrees.”

The evaluation index system on national energy security is in the discussion stage at present, and the comparatively systematic or accepted index system has not been established. So the further study on influencing factors and measurement indicator system based on multi‐dimension of national energy security, is the emphasis of the continued further research.

Constructing the evaluation index system on national energy security integrating PSR conceptual model from the perspective CAS.

Divides the carrier of energy security problem's happening into three energy domains (non‐renewable energy), and introduces the theory and method of CAS to construct the agent layer to carry on the multi‐agent gambling analysis. Simultaneously separately analyses the coal security, the petroleum security as well as the natural gas security using the concept framework of PSR.

The purpose of this paper is to propose a fixed PV energy system design and a sun tracking PV energy system design to meet the primitive energy demands of a typical house in Sakarya, Turkey with energy payback times (EPBT) and greenhouse payback times (GPBT) calculations.

The designs were developed based on the total solar radiation received on the surface of the PV modules. The EPBT and the GPBT of the designs were investigated by utilizing the current embodied energy data of the literature and annual energy output of the proposed systems. The monthly mean total solar radiation, the yearly total solar radiation and the annual energy output of the systems were calculated according to the results of previous studies of authors on 80-W prototypes of a fixed PV energy system tilted at the yearly optimum tilt angle of Sakarya and a two-axis sun tracking PV energy system.

The annual energy outputs of the fixed system and the tracking system were established to be 10.092 and 10.311 MJ, respectively. EPBT of the systems were estimated 15.347 years for the fixed system and 11.932 years for the tracking systems which were less than the lifespan of PV modules. The greenhouse gas emitted to produce and install the systems were estimated to be 6,899.342 kg for the fixed system and 5,040.097 kg for the tracking system. GPBT of the systems were calculated to be 5.203 and 2.658 years, respectively.

PV energy is clean without greenhouse gas emission during the operation. However, significant emissions occur in the life cycle of PV modules until the installation is completed. Therefore reducing the number of PV modules make great differences in the GPBT of PV energy systems. In this paper, comparisons between the GPBT results of the optimally tilted fixed system and tracking system were performed to discuss the best option by means of environmental concerns.

The Heating, Ventilation and Air Conditioning (HVAC) system is a significant energy consumer in built environments, and the building energy consumption could be minimised by optimising HVAC controls. Hence, this paper aims to investigate the applicability of Variable Refrigerant Flow (VRF) air conditioning systems for optimising the indoor comfort of buildings in Sri Lanka.

To address the research aim, the quantitative approach following the survey research strategy was deployed. Data collected through questionnaires were analysed using descriptive statistical tools, including Mean Rating (MR), Relative Important Index (RII) and Standard Deviation (SD).

The findings revealed that VRF systems are popularly used in Sri Lankan apartment buildings. Furthermore, energy efficiency and comfort were recognised as the most significant top-ranked benefits, while ventilation issues and initial cost were recognised as significant challenges. Moreover, the allocation of trained technicians and provision of proper ventilation through a Dedicated Outdoor Air System (DOAS) were highlighted as applicable mitigation strategies for the identified challenges in VRFs.

The study recommends VRF systems as a suitable technology to ensure energy efficiency, reduce GHG emissions and achieve climate performance within the built environment. The opportunities for adopting VRF systems for developing countries could be explored based on the research findings. The identified challenges would assist the design engineers and facilities professionals to devise suitable strategies to mitigate issues of VRF systems in developing countries.

This research provides empirical proof of the energy efficiency and comfort aspects of VRFs. The study has explored and recommended VRF technology as a beneficial application to overcome the persistent energy crisis in developing countries.

Sustainable development calls for a larger share of intermittent renewable energy. To mitigate this intermittency, Compressed Air Energy Storage (CAES) technology was introduced. This technology can be made more sustainable by recovering the heat of the compression phase and reusing it during the discharge phase, resulting in an adiabatic CAES without the need for burning of fossil fuels. The key process parameters of CAES are temperature, pressure ratios, and the mass flow rates of air and thermal fluids. The variation in these parameters during the charge and discharge phases significantly influences the performance of CAES plants. In this chapter, the transient thermodynamic behavior of the system under various operating conditions is analyzed and the impact of heat recovery on the discharge phase energy efficiency, power generation, and CO₂ emissions is studied. Simulations are carried out over the air pressure range from 2,500 to 7,000 kPa for a 65 MW system over a five-hour discharge duration. It is also assumed that the heat loss in the air storage and the hot thermal fluid tank is insignificant and standby duration does not impact the status of the system. This result shows that the system exergy and the generated power are more sensitive to pressure change at higher pressures. This work also reveals that every 10°C increase on the temperature of the stored air can lead to a 0.83% improvement in the energy efficiency. The result of the transient thermodynamic model is used to estimate the reduction in CO₂ emissions in CAES systems. According to the obtained result, a 65 MW ACAES plant can reduce about 17,794 tons of CO₂ emission per year compared to a traditional CAES system with the same capacity.

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.

This study aims to provide and illustrate the application of a framework for conducting techno-economic analyses (TEA) of early-stage designs for net-zero water and energy, single-family homes that meet affordable housing criteria in diverse locations.

The framework is developed and applied in a case example of a TEA of four designs for achieving net zero-water and energy in an affordable home in Saint Lucie County, Florida.

Homes built and sold at current market prices, using combinations of well versus rainwater harvesting (RWH) systems and grid-tied versus hybrid solar photovoltaic (PV) systems, can meet affordable housing criteria for moderate-income families, when 30-year fixed-rate mortgages are at 2%–3%. As rates rise to 6%, unless battery costs drop by 40% and 60%, respectively, homes using hybrid solar PV systems combined with well versus RWH systems cease to meet affordable housing criteria. For studied water and electricity usage and 6% interest rates, only well and grid-tied solar PV systems provide water and electricity at costs below current public supply prices.

This article provides a highly adaptable framework for conducting TEAs in diverse locations for designs of individual net-zero water and energy affordable homes and whole subdivisions of such homes. The framework includes a new technique for sizing storage tanks for residential RWH systems and provides a foundation for future research at the intersection of affordable housing development and residential net-zero water and energy systems design.

Green energy as a transportation supply trend is irreversible. In this paper, a highway energy supply system (HESS) evolution model is proposed to provide highway transportation vehicles and service facilities with a clean electricity supply and form a new model of a source-grid-load-storage-charge synergistic highway-PV-WT integrated system (HPWIS). This paper aims to improve the flexibility index of highways and increase CO₂ emission reduction of highways.

To maximize the integration potential, a new energy-generation, storage and information-integration station is established with a dynamic master–slave game model. The flexibility index is defined to evaluate the system ability to manage random fluctuations in power generation and load levels. Moreover, CO₂ emission reduction is also quantified. Finally, the Lianhuo Expressway is taken as an example to calculate emission reduction and flexibility.

The results show that through the application of the scheduling strategy to the HPWIS, the flexibility index of the Lianhuo Expressway increased by 29.17%, promoting a corresponding decrease in CO₂ emissions.

This paper proposed a new model to capture the evolution of the HESS, which provides highway transportation vehicles and service facilities with a clean electricity supply and achieves energy transfer aided by an energy storage system, thus forming a new model of a transportation energy system with source-grid-load-storage-charge synergy. An evaluation method is proposed to improve the air quality index through the coordination of new energy generation and environmental conditions, and dynamic configuration and dispatch are achieved with the master–slave game model.

Estimates show that close to 90% of the buildings we will need in 2050 are already built and occupied. The increase in the existing building stock has affected energy consumption thereby negatively impacting the environment. The purpose of this paper is to assess determinants of sustainable upgrade of existing buildings through the adoption and application of sustainable technologies. The study also ranks sustainable technologies adopted by the professionals who participated in the survey with an in-built case study.

As part of the overall methodology, a detailed literature review on the nature and characteristics of sustainable upgrade and the sustainable technologies adopted was undertaken. A survey questionnaire with an in-built case study was designed to examine all the sustainable technologies adopted to improve energy consumption in Australia. The survey was administered to sustainability consultants, architects, quantity surveyors, facility managers and engineers in Australia.

The results show a total of 24 technologies which are mostly adopted to improve energy consumption in existing buildings. A factor analysis shows the main components as: lighting and automation, heating, ventilation and air conditioning (HAVC) systems and equipment, envelope, renewable energy and passive technologies.

The findings bridge the gap in the literature on the adoption and application of sustainable technologies to upgrade existing buildings. The technologies can be adopted to reduce the excessive energy consumption patterns in existing buildings.

The purpose of this paper is to describe how, in the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasis has been put on utilisation of the ambient energy from ground source heat pump systems (GSHPs) and other renewable energy sources.

Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. This paper highlights the potential energy saving that could be achieved through use of ground energy source. It also focuses on the optimisation and improvement of the operation conditions of the heat cycles and performances of the direct expansion (DX) GSHP.

It is concluded that the direct expansion of GSHP are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors.

The paper highlights the energy problem and the possible saving that can be achieved through the use of the GSHP systems and discusses the principle of the ground source energy, varieties of GSHPs, and various developments.

The inappropriate lighting methods can have irreversible effects on artworks available in museums and exhibitions. Several factors affect the choice of the lighting system in the museums. By surveying all possible elements, this paper aims to propose a sustainability-based solution, as it relates to the development of artwork conservation, visual perception and energy efficiency during operation and maintenance (O&M).

The paper elicits optimal solutions out of the method presented based on functions and expert opinion to improve lighting quality in existing museums. To study the optimization, the energy consumption and life cycle cost (LCC) in both the proposed lighting and the existing lighting system are compared using HoneyBee and LadyBug plugins in GrassHopper, as well as BLCC5 energy cost estimation software.

The results indicated a practical method to select the most suitable solution for museum lighting. By applying the proposed solutions obtained from the case study, a significant reduction in energy consumption and LCC were achieved. Besides, greenhouse gases were remarkably decreased.

Providing the proper lighting systems for each museum is the issue that is given special attention during the facilities management. The quality of the lighting, energy consumption and costs are analyzed by the simulation software. It is recommended that the validity considerations of the practice are examined.

The present study tried to present an optimal method to choose the best lighting system by the simultaneous utilization of theoretical and practical aspects. The functional model is also introduced for performing the most effective method to enhance the lighting techniques in the art museums.