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In this paper different combinations of solar energy and heat pump systems are compared and investigated through transient system simulations. The focus is on a small capacity heat pump (HP) with a heating capacity rate of 5.36 kW. The building (single family house 140 m 2 ) which are considered in this paper have a space heating demand of about 45 kW h/m 2 a. Based on a conventional air source HP and a parallel solar air source HP system, serial solutions for the combination of solar-HP systems are defined and analysed. For the consideration and evaluation of different systems through transient system simulations, a semi-physical HP-model is used, which offers the possibility to use two evaporators in series. With a combined parallel solar air source HP system the system performance (SPF System = 3.65) can be increased significantly compared to a conventional air source HP system (SPF System = 2.55). Unglazed selectively coated absorbers as source for the HP offer the advantage, that the collector can be used as an air heat exchanger. If solar radiation is available, higher temperatures at the evaporator of the HP can be achieved, compared to a conventional air source HP system. By the integration of unglazed solar absorbers as source for the HP the HP performance can be increased significantly (SPF HP increases from 3.25 up to 3.55 compared to a conventional air source HP). [ABSTRACT FROM AUTHOR]

• The solar louver was proposed to increase direct heat gaining for building. • Effects of blades' angle and characteristics on heat gain of solar louver was quantified. • Indoor temperature was higher and temperature field was more uniform with coupled solar louver. • By comparison with non-coupled solar louver, solar louver in maximum light transmittance mode decreased active heating supply capacity by 33.8%. Promoting solar energy for heating is of great significance for achieving the national goals of "double carbon" goals. Increasing the heat gain of window space could improve the solar energy utilization in congested urban environments. The paper proposed a new heating type for active solar house by solar louver. Thermal effects validation on solar louver were studied by field-test and simulation analysis. A solar louver model was established on the platform of MATLAB and TRNSYS. The simulated results showing that heat gain of solar louver reached the largest when blades' angle was about 10°. Solar louver with high reflectivity and low thermal emissivity could capture more heat gain. The in-situ experiments of active solar house coupling solar louver were carried out in Ordos. From 24th to 29th Jan. 2022, all-day comparative experiments of thermal effects in actual winter-weather were conducted. The experimental results indicating that solar louver in maximum light transmission mode was preferred in active solar house. Compared with the condition of solar louver in overlapped light transmittance mode, maximum light transmission mode could obtain 17.7% higher heat gain. Indoor temperature was more higher and temperature field was more uniform. Moreover, by comparison with the non-coupled solar louver, solar louver in maximum light transmittance mode decreased active heating supply capacity by 33.8%, which could reduce energy consumption of building. The main work here provided a theoretical basis for performance optimization of active solar house. [ABSTRACT FROM AUTHOR]

Actual national and international energy strategies generally encourage the use of renewable energy sources. Thermal energy storage (TES) offers various opportunities in the design of renewable energy systems. Thermochemical heat storage has gained popularity among researches because of higher energy density and lower heat loss compared to sensible and latent heat storage. On the other side solar energy has been recognized as one of the renewable energy sources with the most potential. This paper reviews thermochemical heat storage technologies and systems with emphasis on systems involving solar energy utilization in buildings. The studies are reviewed based on used storage materials, system configuration as well as models to predict and optimize system performance. [ABSTRACT FROM AUTHOR]

The popular operation mode of following thermal load often causes power surplus and efficiency decrease in CCHP (combined cooling, heating and power) systems at part load. CAES (compressed air energy storage) is thus one of the appropriate technologies to improve CCHP part-load efficiency through peak load shifting. However，the output power of CAES is possibly not high due to low temperature of the compressed air entering air turbine. In view of these problems, this paper proposed a gas turbine based CCHP combined with solar thermal energy and compressed air energy storage (S-CAES). The off-design models of gas turbine based CCHP and S-CAES were built. The merits and flaws of two different control strategies of S-CAES were analyzed. The characteristics of the proposed system indicate that the energy efficiency and exergy efficiency are both higher than those of the CCHP system without S-CAES. The performances of S-CAES are mainly influenced by the designed parameters, load distribution of demand side and the capacity of gas turbine. A case study of the proposed CCHP with S-CAES system in an 180000m 2 hotel building located in South China shows that the optimal power capacity of S-CAES comes to 435 kW; and energy efficiency increment gains 1.015% in comparison with a corresponding optimized CCHP system without S-CAES. [ABSTRACT FROM AUTHOR]

Ubiquitous modernization of building energy and management systems brings tendencies for an effective integration of renewables in buildings. This article shows how solar energy can be in charge of energy savings within a building by integration of solar systems with Trombe wall. Numerical calculations of Trombe wall thermal resistance and its performances in comparison with a common wall are considered. Additionally, energy-efficiency gaining by a combination of PV modules and Trombe wall, using simulations by SAM (System Advisor Model) software is discussed. PV module parameters and their impact on its electricity production are observed and analyzed. The PV module parameters, analyzed in the paper are: the tilt angle α of PV modules, incident angle β of direct sunrays on PV modules, normal beam irradiation N and PV cells operating temperature. With bigger incident angle β of direct sunlight on PV modules, the normal beam irradiation is smaller, which brings less electricity production. The impact of PV module operating temperature can be neglected in comparison with the impact of tilt angle on PV module electricity production. The optimal tilt angle of PV modules for generating maximum annual electricity is around latitude angle. It varies with normal beam irradiation to achieve the maximum monthly electricity production. [ABSTRACT FROM AUTHOR]

The temporal fluctuation of solar energy resources often require the utilization of thermal energy storage to increase the level of solar energy. Solar energy systems that are used to meet the heating demands of buildings can be implemented in a variety of system configurations, ranging from energy production and storage at the building-level, to centrally located production and storage components coupled with a district-heating network. In this paper, quasi-steady state simulation models are used to evaluate the impact that different design configurations of decentralized and centralized solar thermal systems (with short- and long-term storage) have on the overall economic cost of the energy provision and the degree of solar energy utilization. A suburban neighbourhood in Switzerland consisting of 11 buildings is selected as a case study. Simulation results suggest that building-level long-term storage configurations out perform all other system configurations in terms of solar fraction and system efficiencies for the given case study. Furthermore, the results demonstrate that the location of the thermal storage and the separation of short- and long-term storage are crucial issues that affect the performance of building-level renewable energy sources, and thus merit further investigation. [ABSTRACT FROM AUTHOR]

This paper deals with a numerical and experimental study of energy performance as well as an economic study of a solar under floor heating system for a traditional bathroom (Hammam). Prior to this, the solar under floor heating system was designed via a parametric study conducted by means of dynamic simulations for the solar collectors area and inclination, the storage tank, the piping materials, the pumps mass flow rates, the temperature regulation and the thickness of the active slab. Moreover, two configurations with or without thermal storage were compared. The Hammam was monitored via air temperature and humidity measurements as well as IR thermography. Good agreement between simulation and experimental results was found with 94% of the discrepancies less than 1 °C. Numerical results show that the system without thermal storage allows the Hammam's operative temperature to reach the desired one. The latter ranges between 30 °C and 37 °C for sunny days in winter, while the system with thermal storage leads to at least 10 °C operative temperature lower compared to system without thermal storage. In addition, the thermal storage system allows having quasi-constant floor temperature that depends on the storage volume, as it avoids large day/night temperature fluctuations thanks to its thermal inertia. Nevertheless, the solar floor heating system configuration with storage tank does not achieve the desired floor surface temperature of the Hammam. Furthermore, it was stated that the best configuration, which leads to an operative temperature of around 35 °C inside the Hammam, is that with cross-linked polyethylene serpentine tubes (PEX) inserted in a concrete slab of 5 cm thickness, 4 m 2 water solar collectors with 80 kg h −1 mass flow rate and temperature regulation difference of 5 °C. On the other hand, the studied solar floor heating system exhibits high to excellent energy performance depending on the use of the Hammam and auxiliary heating is almost not needed for a rational use. Furthermore, the economic feasibility of the solar floor heating system of the Hammam indicates that the annual heating energy consumption is reduced by at least 72%. Moreover, the annual energy savings are about 950 MAD (around 97 USD) and 690 MAD (around 70 USD) respectively compared to the electric and gas heating systems. The payback period of the solar system is then around 6 and 8 years respectively. Over the lifetime of the solar system, which is assumed to be 15 years, its cumulative reduction of the CO 2 emissions is up to 10 tons. [ABSTRACT FROM AUTHOR]

Solar energy is clean and renewable energy; phase change material (PCM), used in buildings, can store the surplus heat and release when needed to save energy in winter. This paper establishes a new model of PCM floor coupled with solar water heating system (PFCSS). A module of PFCSS building was established in TRNSYS. The module was validated by a full-scale experiment. Two experiment buildings, a reference building and a PFCSS building, were set in Ninghe County of Tianjin, China. The experiment lasted for 15 days in February. Two mathematical methods, MRE (mean relative error) and Bland-Altman consistency analysis, are used to evaluate the accuracy of the model. In the comparison of the experiment data and simulation data of PFCSS building, MRE is 0.6% and the result of Bland-Altman consistency analysis is 95.1% (95% confidence interval −1.94–1.46). A model of the control building with ordinary radiant floor was set up to compare the differences in its temperature performance in relation to that of the PFCSS building. PFCSS building’s temperature fluctuation is smaller and the heating process is longer than control building. If the indoor temperature is maintained at 20 °C, the PFCSS building can save 5.87% on the energy consumption, when compared with the control building. Based on these two existing models, the influences of PCM’s thermal physical parameters on the indoor air temperature were analyzed by simulation. [ABSTRACT FROM AUTHOR]

Pitched-roof buildings make up a considerable proportion of architectural roof styles. Precise estimation of solar energy potential on pitched roofs is thus crucial to the sustainable development and renewable energy consumption of human habitats. Conventional solar radiation measurements usually adopt Light Detection and Ranging (LiDAR) data, which can only be extracted from existing buildings. There has been relatively little research assessing solar radiation on pitched roofs. This paper develops a pixel-based approach to estimation of solar energy potentials over pitched roofs based on the pretext of architectural design drawings. A typical Australian house with nine roofs is then chosen for implementation through a case study. The solar radiation on a certain cell of a shadow map is mathematically formulated for each pixel unit. Its yields over a certain time period are calculated by considering multiple instantaneous solar irradiances and visually presented through image processing. The resulting solar radiation maps, especially a coloured 3D map, reveal the roofs’ radiation distribution including effects from objects on the roofs such as chimneys. Radiation contour lines are mapped to obtain installation ranges for solar devices. This study will benefit commercial energy investors, residents and urban planners in the efficient use of renewable energy sources through accurate prediction of solar radiation potential and identification of areas receiving high radiation over sloping roofs. [ABSTRACT FROM AUTHOR]

Precise estimation of solar energy on building roofs plays a critical role in sustainable development and renewable energy consumption of high-density human habitats. Conventional solar radiation models based on costly Light Detection and Ranging (LiDAR) data are only adequate for existing buildings, not for future construction areas. In this paper, a pixel-based methodology is constructed for estimating solar energy potential over roofs. Buildings with flat roofs in a newly planned construction area are chosen as a case study. The solar radiation at a certain cell is mathematically formulated in the pixel unit, and its yields over a certain time period are calculated by considering multiple instantaneous solar irradiances and are visually presented by image processing. Significant spatial and temporal variations in solar radiation are measured. Within the study area, the maximum and minimum annual radiation yields are estimated at 4717.72 MJ/m 2 /year and 342.58 MJ/m 2 /year respectively. Radiation contour lines are then mapped for outlining installation ranges of various solar devices. For each apartment building, around 20% of roof areas can obtain 4500 MJ/m 2 /year or more solar radiation yields. This study will benefit energy investors and urban planners in accurately predicting solar radiation potential and identifying regions with high radiation over building roofs. The results can be utilised in government policies and urban planning to raise awareness of the use of renewable energy sources. [ABSTRACT FROM AUTHOR]

This paper is a full review on the development of solar photovoltaic technology for building integration and design. It highlights the classification of Solar PV cell and BIPV product for building design purpose. BIPV poses an opportunity to play an essential part in a new era of distributed power generation. Building integrated photovoltaic systems is powerful and versatile tool for achieving the ever increasing demand for zero energy building of the coming years. While some critical policy challenges exist, the value of generating power directly where it is used, aesthetic designs and flexible thin film module form factors is just starting to be understood, which may help to mitigate the barriers posed for current BIPV applications. [ABSTRACT FROM AUTHOR]

Nowadays, it is well recognized at the international level that the building sector is one of the biggest energy consumers, which made the intervention in this sector the greatest potential for energy consumption reduction and greenhouse emissions mitigation. In Algeria, building sector is responsible of more than 40% of the final energy consumption. Solar energy systems integrated in buildings can be an important solution to this dual problem. The aim of this paper is to estimate the energy performance of a typical single-family bioclimatic house equipped with a solar heating system located in the north Algeria (Algiers) and to investigate its conversion into a zero energy house by installing a grid connected PV system. To achieve this goal, a numerical model of the bioclimatic house coupled with the solar heating system is developed and validated with experimental data. Then, the validated model is used to optimize the adequate size of the solar heating system and to determine its contribution in the production of thermal energy for both DHW preparation and space heating of the house. Finally, a PV system is sized to supply, in parallel with the utility grid, the house with electricity for lighting, appliance and auxiliary electric heater. Furthermore, an economic analysis is made to show the profitability of integration of grid connected PV and solar thermal systems in building. Results show that the conversion of a bioclimatic house into a ZEH using a grid connected PV system, in the north of Algeria weather conditions, present high level of feasibility. However, the return on investment is very high due mainly to the high cost of solar energy components and the very low costs of conventional energy in Algeria. [ABSTRACT FROM AUTHOR]

This paper investigates the Demand Side Management (DSM) in a commercial building microgrid with solar generation, stationary Battery Energy Management System (BESS) and gridable (V2G) Electric Vehicle (EV) integration. Taking into consideration of a comprehensive pricing model, we first formulate a deterministic DSM as a mixed integer linear programming problem, assuming perfect knowledge of the uncertainties in the system. A two-stage stochastic DSM is further developed that addresses the stochastic nature in solar generation, loads, EV availabilities and EV energy demands. The proposed DSMs are validated with real solar generation, loads, BESS and EV data using sample average approximation. Detailed case studies show that the stochastic DSM outperforms its deterministic counterpart for cost saving for a wide range of prices, though at the expense of higher computational time. Computational results also demonstrate that moderate number of EVs helps to cut down the overall operation cost, which sheds light on the benefit of future large scale EV integration to smart buildings. [ABSTRACT FROM AUTHOR]

In this paper, a new and efficient hybrid AC/DC solar powered Homegrid model is proposed based on the load characteristics of a typical set of home appliances working on a 220 V, 50 Hz system. The load characteristics of home appliances are represented by a static ZIP (constant impedance ( Z ), constant current ( I ) and constant power ( P )) coefficient model, a useful load model in power flow studies. A Homegrid system is formed by analysing the distortion produced by modern household equipment, and a K -factor with a significant role in the overheating of residential/distribution transformers is determined. Further, the ZIP load model is validated by a simulation and the results are compared with experimental data. To improve the efficiency and quality of the traditional Homegrid system, a solar powered hybrid AC/DC supply network model is proposed. This system eliminates redundant power conversion stages and mitigates the loss due to the harmonics by a shift of harmonic intensive loads to the Direct Current (DC) network side. Its effectiveness has been investigated with a simulation in MATLAB as well as with hardware implementation. This proposed energy efficient Homegrid model could be quite helpful in fulfilling the idea of net zero or surplus energy buildings. [ABSTRACT FROM AUTHOR]

EN ISO 13790 is the international standard used for the calculation of the thermal energy requirement of buildings. The evaluation of solar gains through the glazed surfaces is done with a simplified procedure that determines the transmitted solar energy through the transparent surfaces as the product of the normal incidence solar gain coefficient g gl,n and a correction factor F W , that considers the directional aspects of the beam solar radiation. In the absence of adequate national guidelines, the correction coefficient F W in EN ISO 13790 for non-scattering glazing is set constant and equal to 0.90. In this paper, the results obtained by the TRNSYS computer code demonstrate that a generalized use of a constant value of F W = 0.90 provides significant deviations. Therefore, a correlation to evaluate a variable F W coefficient, in function of the incidence angle of solar radiation and of the number of glass panes, is reported. The accuracy of the obtained results was verified comparing the calculated values with those provided by the TRNSYS software. Finally, with reference to two buildings located in two localities with different weather data, the thermal energy needs by applying the EN ISO 13790 procedure with F W = 0.90 and with variable F W have been compared. [ABSTRACT FROM AUTHOR]

Currently, there is no methodical procedure for selecting solar-optical properties of roller shades, which affect the energy and indoor environmental performance of perimeter building zones. This paper presents a new systematic methodology for identifying the range of shading properties (openness factor and visible transmittance) that can significantly reduce the risk of glare. A model that calculates angular beam–beam and beam–diffuse shading optical properties using minimum inputs is used within a hybrid ray-tracing and radiosity daylighting model, validated with full-scale experiments. The temporal variation of beam and total vertical illuminance is used to define the annual visual discomfort frequency and establish a process for selecting the range of acceptable shading properties for each set of external parameters (location, orientation, glazing visible transmittance, and buffer zone). The combined impact of visible transmittance and openness factor on discomfort frequency and daylight metrics is non-linear and complex. Recommendations for openness factors and visible transmittance values are made for different scenarios. Selecting the upper limits of suggested ranges can provide more daylight into the space and reduce the probability of high contrast. These guidelines may be used for selection of shading products, followed by considerations about energy savings and provision of outside view. [ABSTRACT FROM AUTHOR]

Obtained as a research result of conducted project, this paper presents an innovative, energy efficient multipurpose system for a sustainable globally cost-effective building's solar energy use and developed methodology for its dynamic analysis and optimization. The initial research and development goal was to create a cost-effective technical solution for replacing fossil fuel and electricity with solar energy for water heating for different purposes (for pools, sanitary water, washing) in one SPA. After successful realization of the initial goal, the study was proceeded and as a result, the created advanced system has been enriched with AC performance. The study success was based on understanding and combined measurements and by BPS made predictions of AC loads and solar radiation dynamics as well as on the determination of the synergetic relations between all relevant quantities. Further, by the performed BPS dynamic simulations for geographically spread buildings locations, it has been shown that the final result of the conducted scientific engineering R&D work has been the created system of confirmed prestigious to the sustainability relevant performance – globally cost-effective building integrated photovoltaic powered heat pump (HP), assisted by waste water heat recovery, for solar AC, water heating and saving. [ABSTRACT FROM AUTHOR]

The heat transfer performance on the wall has a great influence on the energy conservation and the indoor thermal comfort. Once it can be adjustable according to the requirement, the wall can effectively regulate the indoor temperature, thereby directly reducing the building energy consumption. In this paper, a new type of passive solar energy utilization technology, the wall implanted with heat pipes (WIHP), was proposed, and its heat transfer performance and energy-saving characteristic were investigated theoretically and experimentally with the typical meteorological data of Jinan. The results indicate that the theoretical results agree well with experimental ones. The heat transfer performance of the WIHP is adjustable and controllable, which can reduce the heating load and improve thermal environment. During the winter in a typical year, the heat loss of the south external wall is reduced by 14.47%. Therefore, such a type of wall can apparently improve the indoor thermal environment, which can be popularized in engineering applications. [ABSTRACT FROM AUTHOR]

Traditional air conditioning and heating systems in buildings are fossil fuel based energy systems, which take the main responsible for the carbon emissions. In contrast, using solar energy for air conditioning becomes one of the promising approaches to reduce energy consumptions and negative environmental impacts from buildings. University of California, Merced built a test facility to investigate the technology: solar cooling. The solar system has 54 m 2 external compound parabolic concentrator (XCPC) solar collectors to drive a 23 kW double-effect absorption chiller. This paper first provides the detailed energy performance analysis of the experiments conducted in August, 2012. The data collected from the experiments shows that the system could provide adequate cooling for a test facility between 11AM to 5PM in both sunny and cloudy days. The daily average collector efficiency is at the range of 36% to 39%. The average coefficient of performance (COP) of the LiBr absorption chiller is between 0.91 and 1.02 with an average of 1.0, and the daily solar COP is approximately at 0.374. In addition to the experimental investigation, a detailed life cycle economic and environmental assessment was also performed by comparing the solar systems to the conventional systems in two types of office buildings at three locations at California. Two different solar cooling system configurations were considered: (i) configuration 1 sizes the area of solar collectors and absorption chiller to meet the peak cooling demand, and uses natural gas as the only backup energy source; (ii) configuration 2 sizes the area of solar collectors and absorption chiller to meet half of the peak cooling demand, and uses natural gas as the backup energy source for the absorption chiller, while incorporates an electrical vapor compression chiller to meet the rest half of peak cooling demand. The annual performance predicts that the systems can achieve the annual solar fraction around 55–68%. And the configuration 2 achieves better life cycle economic and environmental performance than the configuration 1. Specifically, the configuration 2 can achieve lower present worth cost during the entire life span than the conventional systems. And both configuration 1 and 2 can reduce the life time carbon footprint by 35–70%. [ABSTRACT FROM AUTHOR]

Traditional windows, as the major source of daylight, have a common problem which is uneven distribution of daylight in the room. Several innovative daylighting systems such as light shelves, fixed and movable reflective louvres, reflective sills, prismatic glazing, light pipes, etc., have been developed to address this problem. This paper reports on a research programme that investigates retrofitted solutions to uneven distribution of daylight in deep-plan office buildings. The work presented here follows initial investigations into the design and applicability of an automated retrofitted panel thermal shutters which can also act as a sunshade and daylighting system. The system has a patented function which allows each shutter/louvre to be controlled and placed separately from other louvres. This study evaluates the effectiveness of the system when acting as a sunshade, light shelf, reflective louvre, and reflective sill under clear, overcast, and sunny sky conditions. According to the results, the system significantly improved daylight distribution and reduced the need for artificial lighting by 60%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Review on application of PCM in trombe wall was performed. • Incorporation of PCMs results in minimizing energy consumption of buildings. • The optimum PCM location into buildings depends on the climate. • Immersion and direct incorporation causes leakage due to heat cycles. • The encapsulation techniques have successfully overcome all of drawbacks. Energy crises and environmental pollution are two of the cardinal obstacles that affect human life today. As part of the efforts to address the excessive energy demands in the last few decades is using renewable energy like solar. As the building sector continues to grow with the growing population, correspondingly, the demand for energy consumption required to heat and cool buildings for thermal comfort augments. To tackle this problem, techniques such as designing green buildings for sustainable architecture have been employed. One of these technologies is the Trombe wall which has been utilized as an avenue for heating buildings using renewable solar energy. Meanwhile, the practice of latent heat storage systems with phase change materials (PCM) is an efficient method to store energy. Substantial research has been carried out to assess the contribution of incorporation of latent heat storage and Trombe walls in buildings on their thermal energy performance. The present review paper communicates a summary of the recent advancements in this topic. The various designs of Trombe walls and different phase change materials types are presented. Research concerning the incorporation of PCM incorporation techniques is scrutinized. Finally, hitherto published literature regarding the applications of PCM in the Trombe wall is underscored and discussed. [ABSTRACT FROM AUTHOR]

Abstract: There are many immediate adverse effects on the environment such as large amount of greenhouse gases and pollutants emissions from the burning of fossil fuels for electricity generation. Photovoltaic (PV) systems are promising solar energy applications to generate electricity without emitting pollutants and requiring no fuel. In modern urban cities, most buildings are high-rise with limited spaces for PV system installation, the concept of building integrated photovoltaic (BIPV) would be an appropriate alternative form of the application. This paper studies a medium size grid-connected BIPV system mounted in an institutional building. Technical data including solar radiation and energy output were analyzed. The operational performance and electricity benefits of the BIPV system were examined in terms of cost, energy and environmental aspects. The monetary, embodied energy and greenhouse gas payback periods were estimated and reported. To shorten the payback periods, the BIPV system should incorporate with more passive energy-efficient architecture designs. This on-site measurement contributes the most accurate method of obtaining reliable data for determining the performance of various designs under the actual operating environments for evaluation. [Copyright &y& Elsevier]

Abstract: In this paper a ray-tracing method is developed to describe the global solar transmittance of louver shading devices. The method is integrated in the dynamic building energy simulation program TRNSYS to assess the cooling demand and required peak cooling power in a south oriented office room. The proposed integrated approach allows calculating the solar transmittance for each time step. As the method is quite complex and requires an important computational effort, this research contrasts the results against the performance of simplified modeling and implementation approaches to assess the performance of louver shading devices. The use of view factor models not accounting for reflections in the shading device underestimates the cooling demand and the peak cooling power. It is shown that representing the shading device as a fixed reduction factor, independent of orientation and shading typology is an unacceptable simplification. However, the use of a simplified implementation of shading factors based on ray-tracing calculations is possible within acceptable margins of error. Best results are achieved by implementing solar radiation weighted monthly averages allowing to estimate the cooling demand and peak cooling power within 3%. [Copyright &y& Elsevier]

Abstract: The sensitivity of low energy and passive solar buildings to their climatic context creates a requirement for accurate local climate data. This situation takes on increasing importance in the context of modelling Passivhaus buildings where the absence of conventional oversized heating and cooling systems implies a greater reliance upon fabric and system optimisation. Conversely, future climatic changes may also pose serious implications for super insulated buildings with inadequate solar shading. Currently, many widely used building performance simulation (BPS) tools still rely on very limited sources of climate data. The following research examines the need for regional and, in some cases, micro-regional climatic data when designing ultra-low energy Passivhaus buildings in the UK. The paper proposes a new methodology for generating this data in PHPP format. The data generated is compared to alternative sources, and the implications discussed in the context of three case studies examining a certified Passivhaus dwelling in a mountainous region of Wales as well as two locations, in close proximity, within London. If correctly implemented the use of such data should provide a more robust basis for future cost and performance optimisation in low energy and passive building design. [Copyright &y& Elsevier]

Abstract: In Brazil, a low-latitude country characterized by its high availability and uniformity of solar radiation, the use of PV solar energy integrated in buildings is still incipient. However, at the moment there are several initiatives which give some hints that lead to think that there will be a change shortly. In countries where this technology is already a daily reality, such as Germany, Japan or Spain, the recommendations and basic criteria to avoid losses due to orientation and tilt are widespread. Extrapolating those measures used in high latitudes to all regions, without a previous deeper analysis, is standard practice. They do not always correspond to reality, what frequently leads to false assumptions and may become an obstacle in a country which is taking the first step in this area. In this paper, the solar potential yield for different surfaces in Brazilian cities (located at latitudes between 0° and 30°S) are analyzed with the aim of providing the necessary tools to evaluate the suitability of the buildings’ envelopes for photovoltaic use. [Copyright &y& Elsevier]

Abstract: A building integrated cooling facade is proposed in this paper. It is a fan-assisted system that consists of two vertical plenums. The first plenum was made of black aluminium transpired plate and a sandtile wall, while the second plenum is formed by the sandtile wall and the building wall. The aluminium plate served as a solar collector and the sandtile wall was an evaporative pad. The reverse side of the sandtile wall that contacted with the air in the second plenum was coated with a water-resistant layer, hence the air was cooled without adding any moisture into it. The facade cooling performance under various operating conditions is investigated through experiment and theoretical analyses. It is found that inlet water temperature is the key factor affecting the cooling performance. In terms of cooling efficiency, the energy consumption to generate 1kW of cooling that cooling the air to 293K is only 0.52W, which is similar to the amount of energy required by some of the solar indirect evaporative cooling and desiccant cooling systems. [Copyright &y& Elsevier]

Abstract: In this paper, design and experimental analysis of glaze photovoltaic thermal (PVT) tile air collector has been discussed. Fabricated glazed PVT tile consists of a single solar cell, duct and fan for extraction of heat associated with the bottom of solar cell. Observations taken at glazed hybrid PVT tile 1 and tile 2 have been considered as case-I and case-II, respectively. Experimental validation has also been performed and it has been observed that that there is a good agreement between theoretical and experimental results with correlation coefficient and root mean square percentage deviation of 0.96 and 7.9, respectively. The performance evaluation in terms of electrical efficiency, overall thermal energy and exergy gain of both the cases has been carried out in indoor conditions at various intensities. It has been found that the electrical efficiency is higher in case-I as compared to case-II. On the contrary the thermal output of case-II is higher than case-I on same intensity and mass flow rate. It has been found that the average electrical and thermal efficiency of newly designed and fabricated glaze PVT tile is 12.4% and 35.7%, respectively. This economical solar simulator can be used by manufactures for testing of different type of photovoltaic tiles as well as photovoltaic modules. [Copyright &y& Elsevier]

Abstract: Presently the essential research trend for sustainable buildings is the use of renewable energy sources and the development of new techniques of energy storage. Phase change materials (PCMs) may store latent heat energy in addition to the typical sensible energy capacity of current building materials, allowing to store significantly more energy during the phase change process (solid to liquid and vice versa). The incorporation of PCMs into building envelope solutions takes advantage of solar energy, contributing to the overall reduction of energy consumption associated to use of the air conditioning systems. This paper presents and discusses research developed in two main components: experimental testing and numerical simulation of a building component with PCM incorporation. The main goal of the experimental testing carried out was to evaluate the effect of the incorporation of PCM macro encapsulated into a typical Portuguese clay brick masonry enclosure wall. It is evaluated the influence of the phase change process of the PCM over the attenuation and time delay of the temperature fluctuations for indoor spaces. The experimental results allowed the calibration and validation of the numerical model, enabling to carry out parametric studies with different PCMs quantity analysing consequent temperature damping and time delay. [Copyright &y& Elsevier]

Abstract: The paper presents the performance of an evacuated tube heat pipe solar collector compared to a concentrated evacuated tube single-sided coated heat pipe absorber for medium temperature applications. The aperture areas of the solar collectors were 0.107m2 and 0.2004m2 for the evacuated tube heat pipe and the concentrated evacuated tube single-sided coated heat pipe absorber, respectively. Experiments were conducted at five different transverse angles (0–40°) with a collector title angle of 60° to the horizontal. These solar collectors were tested over a range of operating temperatures and the mean fluid and ambient air temperature differential increase and outlet and inlet fluid temperature differential, energy collection rates and efficiency and the heat loss coefficients of each solar collector was experimentally measured, calculated and compared to each other. The concentrated evacuated tube heat pipe solar collector showed an improvement of 30% and 25.42% in overall average outlet and inlet fluid temperature differential and total daily energy collection, respectively compared to the non-concentrated evacuated tube heat pipe collectors. [Copyright &y& Elsevier]

Abstract: This paper aims at introducing an improved methodology for the dynamic modelling of buildings by the thermal networks method. This methodology employs, as a tool, the commonly used ASHRAE clear sky model to allow for the calculation of the external façade radiation and the distribution of the penetrating solar flux on the internal surface-nodes of the zone. The zone considered has an entirely glazed façade with a varying type of glazing and its enclosure is a rectangle parallelipipedic. The incident solar radiation is determined for building surface azimuths ranging from east to west in 45° step increments. The mathematical formulation of this solar-angle dependent lumped capacitance thermal model is based on the nodal approach and is updated in 15min time increments. The proposed methodology provides more insight to help understand the impact of opaque and glazed façade orientations and layer-formation on energy consumption. Results from annual energy performance calculations vs glazed-façade orientation, for various glazing systems, are given for a building zone location in the Mediterranean region. Depending on the building façade orientation and climatic conditions, proper selection of the type of glazing can reduce the annual building energy consumption. [Copyright &y& Elsevier]

Abstract: This paper presents a new method for selecting the energy reference year, which may be used for many applications, such as the energy performance of buildings, the simulation of active or passive solar energy systems, HVAC system performance or indoor climate analyses. The EN ISO 15927-4 method was modified by using monthly dependent weighting factors for the main climatic parameters in the calculation of heating and cooling energy demand in buildings. We used data from the cold Finnish boreal climate to demonstrate the method. In a cold boreal climate, during the summer temperature and solar radiation have a similar influence on heating and cooling energy demand, whereas air humidity and wind speed have a minor effect. The principle for determining the weighting factors and modified method for the selection of the energy reference year can also be used for other climatic zones. The weighting factors determined in this study can be used for other countries in a cold climatic area. [Copyright &y& Elsevier]