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Thermal energy storage (TES) systems with phase change materials (PCMs) as a known energy storage technology have a high potential for increasing the energy efficiency of buildings. In fact, the use of PCMs with various approaches, either active or passive, in the building helps to maintain the temperature in the thermal comfort range for occupants through decreasing the temperature swings, and lower energy consumption by the load reduction/shifting. Due to the significance of this issue, many research works have been carried out on the application of PCMs in buildings. In this study, the experimental works in the fields of PCMs in buildings are taken into account. The papers are classified based on heating, cooling, and air-conditioning. Besides these, the applications of nano-PCMs in buildings are reviewed. According to what has been carried out up to now, the gaps are identified and analyzed for preparing useful suggestions for future works. The recommendations and suggestions are presented at the end of the chapters as well as the conclusion, and the literature is summarized in some tables. [ABSTRACT FROM AUTHOR]

This paper investigates factors associated with variation in daily total (electricity and gas) energy consumption in domestic buildings using linked pre-COVID-19 smart meter, weather, building thermal characteristics, and socio-technical survey data covering appliance ownership, demographics, behaviours, and attitudes for two nested sub-samples of 1418 and 682 British households selected from the Smart Energy Research Laboratory (SERL) Observatory panel. Linear mixed effects modelling resulted in adjusted R2 between 63% and 80% depending on sample size and combinations of contextual data used. Increased daily energy consumption was significantly associated (p -value < 0.05, VIF < 5) with: households living in buildings with more rooms and bedrooms, that are older, more detached, have air-conditioning, and experience colder (more heating degree days) or less sunny weather; households with more adult occupants, more children, older adult occupants, higher heating temperature setpoints, and that do not try to save energy. The results demonstrate the value of smart meter data linked with contextual data for improving understanding of energy demand in British housing. Accredited UK researchers are invited to apply to access the data, which has recently been updated to include over 13,000 households from across Great Britain. This paper provides guidance on appropriate methods to use when analysing the data. [ABSTRACT FROM AUTHOR]

Energy demand for heating and cooling of buildings can be minimized through usage of thermal energy storage (TES) systems in building materials. TES in microencapsulated phase change materials provides a new solution to thermally regulated energy efficient buildings. This study summarizes the investigations and analysis of microencapsulated PCMs for building applications. Microencapsulated phase change materials (MPCMs) can be incorporated with many materials that are commonly used in building construction. This paper provides overview of various encapsulation techniques, test methods for MPCMs as well as applications of MPCMs in buildings. There are several micro-encapsulation methods by which the microcapsules of a wide range of sizes between 0.05 μm and 5000 μm can be produced. The MPCM incorporated with concrete, mortar, plaster and other materials have a significant potential to increase the thermal capacity of the mixture. Several authors reported testing of building materials with MPCM. Though the increase of thermal capacity with addition of MPCM is significant the decrease of mechanical properties, such as compressive strength, is relatively small. [ABSTRACT FROM AUTHOR]

The accuracy in assigning a climatic zone to a city is essential for studying the correct sizing of domestic hot water, heating, and cooling systems, as well as of construction materials. In Spain, the current system for allocating climate zones is one proposed by the Código Técnico de la Edificación (Technical Building Code) (CTE) and includes a method based on Royal Decree 235/2013, Procedimiento Básico para la Certificación de Eficiencia Energética de Edificios de los Edificios (Basic Procedure for Certification of Energy Efficiency of Buildings), as well as on the recognized document CERMA to calculate energy demands, CO 2 emissions, and energy ratings. The climatic data of cities is not always available, so the CTE method has proposed some solutions, but they are not always precise enough. In this paper, we propose an alternative classification of climatic zones as a result of applying a new method based on approximation and interpolation functions, with a maximum error of 5.773e − 15 in summer and 6.661e − 16 in winter. This new method has been applied and tested in Andalusia in Southern Spain, a region with 772 municipalities. According to the climatic data available, the new proposed method has resulted in more precise climatic zones than the two versions of the CTE (2009 version and the 2013 update). The results are closer to reality, and the method is exportable to any region. [ABSTRACT FROM AUTHOR]

Being increasingly insulated, new buildings are more and more sensitive to variations of solar and internal gains. Due to an important use of electrical heating systems, especially in housing, France is facing a growing problem of peak load on its electricity grid. Controlling the heating system often constitutes an efficient solution to shift heating loads while maintaining indoor comfort. The proposed energy management is a predictive set of optimal commands issued from a dynamic programming optimization knowing in advance the weather, occupancy and internal gains for the next 7 days. This method is tested on a low energy house situated in France with an annual heating demand of 14 kWh/m 2 . In this paper, load shifting according to utility rate incentives and carbon emissions are studied. The importance of building models as well as envelope insulation and thermal mass on energy management results is shown. [ABSTRACT FROM AUTHOR]

This paper proposes a new method for an optimal control of the heating system at the building scale. This control is a new approach of energy planning that aims to decrease the heating consumption/expenses over a defined prediction horizon while respecting the occupants’ thermal comfort. It employs a simplified building thermal model to simulate the building thermal behavior taking into consideration the weather predictions. This approach is based on the application of Monte Carlo method, i.e., a random generator for the heating system scenarios. The aim is to determine the optimal heating plan for the prediction horizon that fulfills the constraints regarding the thermal comfort of occupants and the minimization of the energy consumption/expenses together with achieving a load shedding. [ABSTRACT FROM AUTHOR]

• Moisture needed to be removed in three building types is calculated. • Salt supported porous composites satisfy most climates and building types. • Zeolites are suitable for return air state, ARI summer and ARI humid climates. • Polyelectrolytes can cope with humid climates and buildings with high wet load. Energy conservation and emission reduction have become a global consensus. As a novel promising energy-saving dehumidification technology, desiccant coated heat exchanger (DCHE)-based air conditioning systems have attracted immense attention recently. This paper provides a quick and reasonable selection of desiccant materials for DCHE systems using water as the cooling medium in different buildings and climates. By the theoretical calculation of moisture needed to be removed in three types of buildings (offices, residential buildings and restaurants) and the analysis of the dehumidification capacity of desiccants in DCHEs reported in the literature, optimal desiccants for different building types and ambient air conditions under given parameters are recommended. Salt-supported porous composite desiccants possess flexible dehumidification performance and can be utilized in most climates and building types, except for extremely humid indoor environments with high requirement for fresh air. Zeolites are especially suitable for return air states, American Air-Conditioning and Refrigeration Institute (ARI) summer and ARI humid climates in buildings with moderate indoor moisture gain, such as offices or residential buildings. Polyelectrolytes can be applied in humid climates and buildings with high indoor wet loads, such as restaurants. This paper offers a promising route to the applications of desiccant materials in novel energy-saving air conditioning technologies. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents an extended method for exergy analysis of buildings and Heating Ventilation Air Conditioning (HVAC) systems, according to an energy demand build-up model from the building side to the energy supply side. The HVAC systems comprise a thermal energy emission and control system, a thermal distribution system, an electricity distribution system and an energy conversion system. Energy and exergy that are required by a building and a HVAC system are posed into the external part and classified by different forms of energy carriers. The external part is out of the boundary of the study. The method is illustrated with an office building equipped with low-temperature heating and high-temperature cooling systems situated in the Netherlands. Thermal exergy and thermal energy demands of the building and thermal energy and thermal exergy losses occurring in the HVAC systems are discussed. The building and the HVAC systems to be considered meet standard Dutch energy performance regulations. Nevertheless their overall exergy efficiencies are low in both cases (17.15% and 6.81% subsequently). The exergy analysis also pinpoints that the thermal energy emission and control system and the energy conversion system are the main causes of the exergy inefficiencies in the heating and cooling cases, respectively. [Copyright &y& Elsevier]

Abstract: Trigeneration systems, also known as Combined Heat, Cooling and Power (CHCP) systems, are interesting alternatives to supply different energy services in urban districts and in large buildings, particularly in warm areas such as Mediterranean countries. These systems can provide substantial benefits from economic, energetic, and environmental viewpoints, since the cogenerated heat can be used for heating in winter as well as cooling in summer with an absorption refrigerator. This paper develops an optimization model using Mixed Integer Linear Programming (MILP) to determine the type, number and capacity of equipment in CHCP systems installed in the tertiary sector as well as to establish the optimal operation mode for the different plant components on an hour-by-hour basis throughout the year. The objective function to be minimized is the annual total cost. The optimization model considers the legal constraints imposed to feed the surplus autogenerated electricity into the grid at a regulated feed-in tariff. The optimization model is applied to design a system providing energy services for a hospital located in the city of Zaragoza (Spain). The effects of the financial market conditions and energy prices in the optimal structure of the system are analyzed. [Copyright &y& Elsevier]

Abstract: Exergy is naturally related to the concept of quality of energy. Therefore, exergy analysis has been widely applied in parallel with energy analysis in order to find the most rational use of energy. Within the built environment a wide margin for exergy saving may be found. Actually, buildings require mostly low quality energy for thermal uses at low temperatures and nowadays their energy demand is mainly satisfied with high quality sources. Exergy analysis of renewable energy-based climatisation systems may be considered an emerging field, where different and often contrasting approaches are followed. Then, in this paper a comprehensive and critical view on the most recent studies on this topic is presented. Special attention is paid to the methodological aspects specifically related to climatisation systems and renewables, and to the comparison of the results. Main renewable energy-based heating and cooling systems are considered in detail. Finally, conclusions regarding the state of the art and possible trends on this field are derived, with the aim to highlight future research issues and promote further developments of this method. Furthermore, conclusions regarding the usability of the exergy method as a tool to promote a more efficient use of available energy sources are also derived. [Copyright &y& Elsevier]