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[Display omitted] • A characterization of each component within a solid desiccation plant is carried out. • An experimental investigation was conducted on desiccant plant installed for the 1st liver on the Algerian coast. • The system was simulated with TRNSYS and validated against experimental data collected under Algerian climatic conditions. An experimental investigation of a solid desiccant cooling system for a research laboratory on the Algerian coast has been carried out. The system utilized flat-plate solar collectors for regeneration and was evaluated through a combination of individual component characterization, system modeling (using TRNSYS), and experimental validation. The results obtained have been validated and show that the efficiency of the rotary heat exchanger reached 65 %, the evaporative humidifier efficiency reached 94 %, and the desiccant wheel achieved efficiencies of 73 % on the process side and 66 % on the regeneration side. This translates to a significant dehumidification effect, reducing absolute humidity in the treated air by 9 g/kg, for the supply air temperature effectively maintained at a comfortable 24 °C. The close agreement between the simulated and experimental COP values (1.13 and 1.08, respectively) validates the chosen approach and confirms the potential of this technology for energy-efficient building cooling in the hot and humid Mediterranean climate of northern Algeria. [ABSTRACT FROM AUTHOR]

• Genetic algorithm-based model predictive control (MPC) of solar cooling system using solar resource and load forecast. • First known results for MPC control of high temperature heat driven triple effect chillers. Hourly simulation results to understand the dynamic system behavior, 10 days and 50 days simulations. • Comparison against rule based controller provided. Results show MPC can exploit new operational features of the system such as variable speed operation of the solar loop pump. • MPC uses stored energy in the tank more optimally to reduce backup energy use providing cost function benefits compared to a standard controller. • Multiple day simulations showed MPC benefits are dependent on the radiation availability. This work presents the benefits of using a model predictive control (MPC) approach for controlling a high efficiency absorption chiller-based solar cooling system with thermal energy storage, incorporating perfect solar resource and load forecasting information. A dynamic physics-based model of the solar air-conditioning system has been built for studying the system behavior. A genetic algorithm based predictive controller is utilized to minimize backup energy consumption while satisfying the cooling demand. The simulations have been carried out using the open-source programming language Python. Detailed investigation of the role of the predictive controller and its decision strategy have been carried out using ten and fifty days simulations. Effect of storage tank heat losses has been investigated. For the simulated example case pertaining to a building, results show the model predictive controller usage delivers about 10% reduction in auxiliary energy use in the system. This is achieved through reduction in tank heat losses, better utilization of heat stored in the tank. It is seen that the MPC based controller enables new system operational capabilities by running the solar collector pump in variable flow mode and allowing the simultaneous heat delivery from storage and backup devices. Opportunities to improve the MPC benefits have been identified. The benefits of the MPC are seen to be sensitive to the system parameters and specific constraints. In summary, this paper provides valuable insights into solar cooling system design and control. [ABSTRACT FROM AUTHOR]

Solar driven cooling systems can be a promising alternative to traditional electrical grid powered air conditioning plants. These systems use either thermal or electrical processes to convert solar radiation into cooling. Despite the numerous theoretical and experimental researches that have been carried out in recent years on solar cooling it is still not clear which system presents the best performance. In this study the performance of three different solar cooling systems is examined, namely: 1) a solar electrical, 2) a solar thermal and 3) a hybrid solar electrical-thermal cooling system. The first one system uses PV collectors in order to supply a conventional electrical vapor compression chiller. The second one utilizes thermal collectors in order to power a heat driven adsorption chiller and the third one utilizes PV/T collectors to feed both an electrical and an adsorption chiller. The study is performed for Athens, Greece climatic conditions during an assumed summer period from May to September. The optimum tilt angle of the solar collectors is calculated for maximization of the solar radiation during summer period. It is found to be 14°. The best performance is observed for the solar electrical cooling system utilizing the mono-Si PV modules with a maximum Solar COP of around 0.47 while the lowest is presented by the a-Si PV modules powered cooling system with a minimum Solar COP of about 0.13. [ABSTRACT FROM AUTHOR]

A novel solar cooling system, i.e., the solar absorption-subcooled compression hybrid cooling system (SASCHCS), is a better solution for large-scale buildings with many floors, but the thermodynamic characteristics of the system are not adequately realized. The thermodynamic model of the hybrid system is absent, and the design of the nominal cooling capacity of the absorption subsystem and the volume of the storage tank are not known. Consequently, this paper primarily examined the thermodynamics of SASCHCS. A thermodynamic model of the hybrid system was developed, and the working process and performance of the hybrid system for different nominal cooling capacities of the absorption subsystem and the volumes of storage tanks were analysed in detail. The influence of selected parameters on the performance was discussed. It was found that the performance of the system first increases and subsequently decreases gradually with improvement in the nominal cooling capacity of the absorption subsystem. The appropriate ratio of the nominal cooling capacity of the absorption subsystem to the area of the collector should be 0.148 kW/m 2 to 0.222 kW/m 2 . Additionally, the performance of the hybrid system increases first but subsequently decreases gradually with the decrease in volume of the storage tank. An appropriate decrease in the volume of the storage tank is recommended. This paper contributes to a deeper understanding of SASCHCS. [ABSTRACT FROM AUTHOR]

This study provides a decision support approach for selecting the best size of the main components of a small scale solar assisted, silica gel-water, adsorption cooling system in arid areas located in Assiut, Egypt. To achieve the objective of this work, an optimization based on a computer simulation has been performed on the design variables, which are: solar collector area, the volume of the hot storage tank, the volume of the cold storage tank, and thermostat set point of the auxiliary heating element. Economic and environmental evaluations of the proposed systems have been performed as well. A validation of the model results is performed with the experimental results of solar driven silica gel-water adsorption cooling system at Assiut University Campus which has worked since 2012. The results show that the tilt angle of 5 ° for the surface of the solar collectors achieved the best absorbed solar radiation by the collector filed. For all proposed systems, the solar fraction did not affect the volume of the cold water storage tank while it has a significant effect on the area of the solar collector field and as well as the volume of the hot water storage tank. The initial cost of the proposed systems ranges from 2897 €/kWc to 4808 €/kWc and this can be considered as a hindrance to spreading at the commercial level. Meanwhile, the running cost over a year achieves low values, and it ranges from 13.9 €/kWc to 99.11 €/kWc.The proposed systems of lower solar fraction give lower carbon dioxide emissions. The carbon dioxide emissions range from193 kg of CO 2eq. /kWc per year for the fully solar driven cooling system to 1062 kg of CO 2eq. /kWc per year for the cooling system fully driven by natural gas. Based on the solar saving approach the proposed system of 24 m 2 solar collector area, 0.6 m 3 hot storage tank, and 1 m 3 cold storage tank with 94 °C auxiliary heater set-point temperature can be considered as the most economically feasible solution. [ABSTRACT FROM AUTHOR]

In this study, the performance of a prototype thermoelectric heating/cooling unit is investigated. In the numerical analysis, temperature–pressure contours, and velocity vectors are obtained for the selected fin geometry. In order to validate the numerical results, experimental analyses are carried out. The effects of the air velocity on the temperature distribution of the fin surfaces and the variation of the psychrometric properties of the air are measured for various TEC voltage differences. Thermal images are used to obtain the temperature variation on fin surfaces. COP values for heating and cooling are calculated. For different fan speeds, the heating and cooling COP values vary between 2.5 and 5, and 0.4 and 1, respectively. The study shows that it is possible to use TECs as an alternative method for HVAC applications with properly designed heat exchangers. Integrating them with photovoltaic panels provides utilization of solar energy, especially in cooling applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] Appraisal of the impact of passive strategies on the energy requirements of a solar cooled building in Tunisia. [•] Comparative simulations of different envelope characteristics. [•] Effect of storage walls and solar overhangs on the thermal performance of the building. [•] Simulation of a predictive model featuring passive strategies and renovation measures. [ABSTRACT FROM AUTHOR]

Abstract: This work describes a novel HVAC system consisting in a solar-assisted absorption ground coupled heat pump (GCHP). The aim of this work is to analyze some of the influence parameters on its energy efficiency. The installation has a complete instrumentation which provides instantaneous information on its actual behavior. The monitoring system consists mainly of temperature probes and flow-meters located in the main five water circuits of the installation: the three circuits that enter the absorption GCHP (generator, condenser and evaporator), the radiant floor circuit and the geothermal circuit, the information is collected by a communications network and data is stored in a database for further reference and analysis. The experimental plant is located in a tertiary-use building in Valladolid (Spain). A model of the experimental installation has been developed using the TRNSYS software. The model has been validated with experimental results obtained in the installation for its cooling mode operation during the summer of 2011. For a defined control strategy, the influence of the generator and condenser temperatures on the heat pump COP and on the overall system energy efficiency is analyzed. [Copyright &y& Elsevier]

Highlights: [•] Indirect and direct air-cooled LiBr–H2O absorption technology is compared. [•] First time this comparison is made experimentally. [•] The power source was a field of flat panel vacuum solar collectors. [•] The outdoor dry bulb temperatures from 28 to 37.7°C. [•] With the direct system higher t ig, lower t oe and higher COP are obtained. [ABSTRACT FROM AUTHOR]

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: Transparent solar thermal collectors (TSTC) represent a new development. An adequate model is needed to predict their performance. This paper presents a collector model with an advanced calculation of the transmission of diffuse radiation and a connection to the building which allows analysis of the collector gains and of the g value, also called “solar factor”, “solar heat gain coefficient (SHGC)” or “total solar energy transmittance”. The model is implemented as a TRNSYS Type and a coupled simulation between a collector and a room is presented for different façade constructions. Façade areas with glazing and venetian blinds are simulated with a second new TRNSYS Type which introduces high modelling accuracy for façades with solar control systems. An HVAC system is presented together with a first estimate of possible reductions of primary energy. It indicates primary energy savings of about 30% by replacing opaque walls with transparent collectors. The g values prove to depend not only on the irradiation, but also on the operation of the solar collectors and vary e.g. between 0.04 and 0.21. Detailed modelling of active façades like TSTC is therefore essential for accurate predictions of the collector gain, the heating and cooling loads and the thermal comfort. [Copyright &y& Elsevier]

Abstract: In the current article, research on the possibilities for ensuring thermal comfort through the use of an adsorption cooling system supplied by solar energy is presented. The main goal was to ensure an adequate level of cooling in a referential room of 40m3 in volume. Cooling was attained by an adsorption ice water generator (AIWG) that was supplied by energy from flat-plate solar collectors. Experiments on the AIWG working conditions and an analysis of the possibilities for using solar energy in a region of Czestochowa (Poland) to supply an adsorption cooling system are also presented. The real value of the cooling efficiency of the COP coefficient for the adsorption ice water generator was 0.27, and the real global efficiency of the adsorption cooling system was 0.23. On the basis of the results, it was assumed that, in climate conditions typical for Poland, it is possible to effectively use the adsorption cooling system to keep a constant level of thermal comfort during all months in which there is a demand for cooling, i.e., between April and October. [Copyright &y& Elsevier]

Abstract: In the last recent years, research in thermal comfort during summer has induced a significant increase in electricity consumption in buildings due to the notable use of mechanical vapor compression air conditioners. Solar cooling systems are an attractive alternative to overcome this problem. The development of these systems requires a fundamental approach with the development of numerical models to predict the behavior of the whole installation. The ultimate goal is to estimate the comfort, the refrigerating power, the power consumption and the overall performance of the facility based on external factors (solar radiation, outside temperature, occupancy in the building). For this, we chose the EnergyPlus environment that is proving to become a reference tool in the field of building simulation. This simulation tool facilitates the coupling of energy systems to the building with a wide range of models (solar thermal collectors, absorption chiller, stratified storage tanks, cooling tower). In this paper, we present the modeling of the solar cooling installation “RAFSOL” within the EnergyPlus environment at the Technology University Institute (IUT) of Saint Pierre in La Reunion. The simulations are then discussed and compared with data extracted from our experimental platform. Then, the model is used to propose a solution to improve the seasonal performances of the installation. [Copyright &y& Elsevier]

Abstract: In this study, experimental trials were conducted on an innovative solar-driven, directly air-cooled, single effect, 4.5kW-LiBr/H2O absorption chiller prototype. The aim was to air-condition a 40-m2 room located in Madrid. The solar facility consisted of a vacuum flat-plate collector field, with a total aperture area of 42.2m2, a 25-kW external plate heat exchanger and a 1.5-m3 storage tank. The paper reports the findings in detail, including solar cooling facility temperatures and thermal power, solar fraction, COP and SCOP values on a day when the outdoor dry bulb temperature ranged from 30 to 37.7°C. The daily results for the entire trial are also given. No solution crystallization problems arose inside the prototype even when the generator feed temperature reached 109°C. The lowest chilled water temperature attained was 14.3°C, and the mean COPth and SCOP values were 0.53 and 0.06, respectively. This study forms part of a larger project whose aim is to use solar power as a source of heat in air-cooled absorption chillers in residential buildings. [Copyright &y& Elsevier]

Abstract: This study has been carried out with a building experimental solar facility based on a 9-year-old field of 50m2 flat plate solar collectors located south of Madrid, Spain. Building domestic hot water production and heating and cooling applications were implemented in the facility. Experimental data corresponding to 100 operating variables (mainly temperatures and flow rates) were recorded during an entire year at intervals of 10min, and from this data, all of the relevant performance parameters were derived. Three thermocouples measured the centre point instantaneous temperatures of the glass cover, the box back surface and the absorber plate of one of the collectors. A 1D collector transient model, based on thermal resistances and capacitances, has been developed and validated with the experimental database. Both experimental and modelled collector thermal energy output and outlet temperatures were obtained under instantaneous real operating conditions. The individual effect on the drop of the thermal energy output can be summarised in the following yearly averaged values: 15.0% due to collector surface aging, 15.7% due to thermal loss produced by wind velocity magnitude and direction, ±3.2% variations due to thermal capacitance and 7.6% due to incident angle of irradiance. Finally, the repercussions on the performance of the real applications are discussed. [Copyright &y& Elsevier]

Abstract: Solar cooling is emerging as one of the most interesting applications in the harnessing of solar energy for alternative uses. Current devices can effectively control the climates of small buildings while addressing the issues associated with the excessive thermal energy captured during the summer months. This article presents an exergy analysis of buildings with solar thermal systems used for Domestic Hot Water (DHW) production and heating and cooling support. The cooling system analyzed is a LiCl–H2O thermally driven heat pump with integral energy storage that uses outdoor swimming pools as heat sink. All subsystems were integrated into the model and considered as a single energy system, and data from installations in three different locations were used. The influences of the heating and cooling demand ratios and the dead state and house temperatures were analyzed. Further, the use of dissipated energy was analyzed, demonstrating that the proposed method facilitates the realistic study of these systems and provides useful analytical tools for improving the overall exergy performance. The energy delivered for heating, cooling and DHW production strongly influences global performance, suggesting that the appropriate sizing of each system is a priority. [Copyright &y& Elsevier]

Abstract: This paper presents the development of a method to optimize a solar-assisted cooling system with limited budget constraints. Regression analysis is used to identify the relationship between the solar fraction and the system factors according to the data provided by experiments. In order to obtain an accurate model to estimate the problem using small number of experimental trials, the method of central composite design (CCD) from design of experiment (DE) is used as a key technique. The experimental trials are conducted in the transient energy system simulation (TRNSYS) tool. Finally, the optimization problem is formulated and solved by including the model as the objective function, the physical constraints of the system factors, and the budget limit. A case study was conducted to apply this optimization method to the design of a solar-assisted double-effect absorption cooling system installed in a small-sized office building in West Lafayette, IN, USA. The results show the developed optimal model strongly agrees with the physical system model in TRNSYS. This optimization method can be generally applied to different types of solar cooling systems, and other renewable energy systems. [Copyright &y& Elsevier]

Abstract: This work presents an experimental validation of a simplified approach for a desiccant wheel model, based on the concept of the analogy method and the formulation proposed by Jurinak for the respective combined potentials. The present work experimentally investigates the validity of the assumption of the efficiency factors of the wheel, with regard to the combined potentials, remaining constant over a sufficiently wide range of operation conditions. The results prove the validity of the discussed assumption. The same analysis is implemented with regard to the technical data about the performance of the wheel, usually provided by the manufacturer in the form of software, the results being also positive. Thus, the respective efficiency factors can be calculated through a limited number of measurements, or even simpler, through the use of the manufacturer''s performance software accompanying the product. [Copyright &y& Elsevier]

Abstract: A solar-assisted HVAC system was retrofitted in 2006–2009 onto an earlier (1980) energy-efficient building. A hybrid system of flat plate and vacuum tube solar collectors heats water in a large hot storage tank that is delivered to an absorption chiller in the cooling season or directly to heating coils in the heating season. Large chilled water storage tanks are charged off-peak and discharged during the day, cooling the building in parallel with the chiller. Measurements of the seasonal performance of the system are presented. Good overall agreement between actual measurements and earlier numerical modeling results is reported for our system, with one notable discrepancy attributable to the operation of the air terminal units, which requires tuning. In cold seasons, solar thermal energy can easily displace a large fraction of traditional heating sources. In the cooling season, the conversion of heat to cooling capacity incurs several parasitic losses, which if not accounted for properly in the design stage, have the capacity to completely offset any advantage gained from the solar system. The economics of building-scale solar thermal systems are strongly dependent on the cost of energy, and electricity in particular. The economics are favorable where electricity costs are high, and vice-versa. [Copyright &y& Elsevier]

Abstract: In the last few years, thermal comfort research in summer has significantly increased the electricity consumption in buildings. This is mainly due to the use of conventional air conditioning systems operating with mechanical vapor compression. Solar cooling systems appear to be an interesting solution to solve this problem. But the understanding of this technology has to be refined through fundamental studies by developing numerical simulations. Moreover, the study of pilot plants is a practical method to gain experience by analyzing all the processes behind solar cooling technology. This paper presents an experimental study of a solar cooling absorption system implemented in Reunion Island, located in the southern hemisphere near the Capricorn Tropic. The particularity of this project is to achieve an effective cooling of classrooms, by a solar cooling system without any backup systems (hot or cold). The aim of this experimental study is to define the limits of the use of such system under tropical climate conditions without setting a set point temperature. Indoor thermal comfort is achieved by a self-stabilizing operating system that maintains the indoor temperature 6°C below the outdoor temperature. During some critical periods of the year, when the outdoor temperature is very high and when the solar cooling system cannot provide enough refrigerating production, thermal comfort inside the building is achieved by using ceiling fans. Firstly we will present the installation and the choices we made in the control and design process. In the second part, an analysis of the experimental results will be presented. [Copyright &y& Elsevier]

Abstract: Air conditioning of buildings is responsible for a large percentage of the greenhouse and ozone depletion effect, as refrigerant harmful gases are released into the atmosphere from conventional cooling systems. The need to implement advanced new concepts in building air conditioning systems is more crucial than ever today. Solar cooling systems (SCS) have the advantage of using absolutely harmless working fluids such as water, or solutions of certain salts. They are energy efficient and environmentally safe. They can be used, either as stand-alone systems or with conventional AC, to improve the indoor air quality of all types of buildings. The main goal is to utilize “zero emissions” technologies to reduce energy consumption and reduce CO2 emissions. Amongst cooling technologies, absorption cooling seems to have a promising market potential. In this paper, the performance and economic evaluation of a solar heating and cooling system of a hospital in Crete, is studied using the transient simulation program (TRNSYS). The meteorological year file exploited the hourly weather data where produced by 30-year statistical process. The required data were obtained by Hellenic National Meteorological Service. The objective of this study is to simulate a complete system comprised of a solar collector, a storage tank, a backup heat source, a water cooling tower and a LiBr-H2O absorption chiller. The exploitation of the results of the simulation provided the optimum sizing of the system. [Copyright &y& Elsevier]

[Display omitted] • An LCA has been performed for an experimental HVAC compared to conventional HVAC. • The experimental HVAC is more environmentally friendly than the conventional HVAC. • The environmental performance of the experimental HVAC can be improved by weight reduction and material reusing. • The phase with the greatest environmental impact in experimental HVAC is the manufacturing phase, while in the conventional HVAC it is the use phase. Solar heating ventilating air conditioning systems are useful tools to meet the objectives of the European Commission in terms of sustainability in buildings, since their use can reduce the environmental impact, including CO 2 emissions, due to their low energy consumption. In order to quantify the improvement that in environmental terms the use of this type of system could entail, in this work it was carried out (a) a comparative life cycle assessment of a solar heating ventilating air conditioningsystem based on evaporative cooling and desiccant wheel with a conventional direct expansion system; and (b) an analysis of feasible modifications of the desiccant wheel based system and their influence on the life cycle analysis results. The experimental desiccant wheel based system showed a slightly higher environmental performance than the conventional direct expansion based system, between 2% and 10%, for the 3 impact categories evaluated: human health, ecosystem quality and resource consumption. When weight optimisation and the reuse of materials were considered, the environmental performance of the experimental based system became even up to between 22% and 50% higher than that of the conventional direct expansion based system. That involved a 60 % reduction in climate change potential indicator, which mainly was influenced by CO 2 emissions. [ABSTRACT FROM AUTHOR]

Abstract: The paper contributes to the system design of solar thermal absorption chillers. A full simulation model was developed for absorption cooling systems, combined with a stratified storage tank, steady-state or dynamic collector model and hourly resolved building loads. The model was validated with experimental data from various solar cooling plants. As the absorption chillers can be operated at reduced generator temperatures under partial load conditions, the control strategy has a strong influence on the solar thermal system design and performance. It could be shown that buildings with the same maximum cooling load, but very different load time series, require collector areas varying by more than a factor 2 to achieve the same solar fraction. Depending on control strategy, recooling temperature levels, location and cooling load time series, between 1.7 and 3.6m2 vacuum tube collectors per kW cooling load are required to cover 80% of the cooling load. The cost analysis shows that Southern European locations with higher cooling energy demand lead to significantly lower costs. For long operation hours, cooling costs are around 200€MWh−1 and about 280€MWh−1 for buildings with lower internal gains and shorter cooling periods. For a Southern German climate, the costs are more than double. [Copyright &y& Elsevier]

• Conjugate and dynamic simulations of adsorption-based solar-cooled buildings. • Validated computational models for buildings and adsorption cooling systems. • Optimization of the adsorption cycle duration based on the operating temperatures. • Variable cycle duration approach reduces auxiliary heating or solar collectors area. • Solar adsorption cooling can provide carbon dioxide emissions avoidance of 28.1–90.7%. Adsorption cooling systems (ACS) may contribute towards a sustainable way of satisfying the increasing cooling demand, as they utilize solar thermal energy and employ non-ozone-depleting substances. Apart from the intrinsic ACS performance, the successfulness of its operation depends on its integration within the entire thermal system (solar collectors, thermal storage and building), which is not straight-forward due to thermal inertia effects and its inherent cyclic operation. Numerical simulations can contribute in understanding the system behavior, its adequate dimensioning and the implementation of optimized control strategies. A computational model was developed, capable of performing conjugate, dynamic simulations of the entire thermal system. The influence of the control criteria is investigated and quantified through three simulation phases, conducted for various solar collectors areas and storage volumes. Higher solar fraction is achieved for lower auxiliary heater activation temperature and lower temperature difference activation of the solar pump. Subsequently, simulations with variable cycle duration were performed, using optimized cycle duration according to the instantaneous operating temperatures. This approach reduces significantly the auxiliary consumption or satisfies the demand with less solar collectors. The potential CO 2 emissions avoidance is calculated between 28.1–90.7% with respect to four scenarios of electricity-driven systems of different performance and CO 2 emission intensity. [ABSTRACT FROM AUTHOR]

• The design and the construction of the first Eenrgy+ autonomous building in Dubai is presented. • A 40 kWp PV field coupled with a 48 kWh electric storage makes the building energy-autonomous 24/7. • The internal comfort is assured by a solar cooling system, without power import from the grid. • Thermal envelope and energy systems are fully instrumented: the monitored perfomance is in very good agreement with the model prediction. This work presents the measured performance data related to the very-first Energy+ building in Dubai certified by the Passive House Institute. The building is a two-floor office structure, with 550 m2 total surface, designed under the guide and the scientific supervision of a Bergamo University research group, jointly to the Mohammed Bin Rashid Space Centre (MBRSC). The goal of the project was to assure a high level of internal comfort all over the year by using only solar energy. The building architecture has been designed to minimize the cooling load and the energy demand. The energy system is based on a 40 kW p PV field coupled with a 48 kWh electric storage and a high-efficiency chiller (reversible heat pump). Transient simulations by Trnsys code have been carried out to optimize both the thermal envelope and the energy plants so to make the building energy-autonomous 24/7. The numerical predictions of the energy performance (including cooling load, PV production and power consumption for chiller, lighting and appliances) are compared to the real data measured by a sophisticated monitoring system, including sensors located in the roof, in the external walls and in the energy systems. The field measurements confirm that the model predictions were accurate both in terms of peak and annual values. The small variations between prediction and real data show that both thermal envelope and PV field perform better than expected. This building is a pioneering pilot-project: the goal was to show that new sustainable construction standards using only solar energy are possible in the United Arab Emirates (UAE) and that this is a viable solution to reduce the carbon footprint in all the Gulf region. The strategic importance of an accurate modeling activity leading to an optimal design has been proved. The monitored data under real operating conditions have confirmed that the expected targets in terms of energy savings and carbon footprint reduction have been successfully achieved. [ABSTRACT FROM AUTHOR]