Phase Change Materials Panels Research Articles

Indoor thermal comfort assessment using different constructive solutions incorporating PCM

Sustainable energy and thermal retrofit design of buildings or districts has a strong global impact in the viewpoint of economies and energy-efficiency perspectives. Several aspects such as architectonic design, building materials, construction technology, mechanical systems and outdoor climate determines the thermal behaviour of buildings and their ability to provide indoor thermal comfort to occupants. The use of geothermal energy and phase change materials (PCMs) in the construction systems are an opportunity that may attenuate indoor air temperature fluctuation as well as overheating risk. This paper presents the results of a study on indoor thermal comfort and energy efficiency regarding the PCM’s positive role when applied to new constructive solutions, inside a building with a geothermal system linked to the air conditioning system. The PCM study was based on real and simulated investigations in two rooms of a new university department at the Aveiro campus. Higrothermal monitoring (indoor air temperature) of two rooms in which one of them has PCM panels incorporated into gypsum board partition wall and into a suspended ceiling. The scope was driven to investigate the potential of these solutions for overheating mitigation. The numerical study was conducted by using an evolutionary algorithm coupled with the software EnergyPlus® used in simulations. In the scope of this optimization process, constructive solutions with the incorporation of different types of PCM with different melting temperatures and enthalpy, and different flow rates of natural ventilation were combined to investigate the potential and the payback time of these novel solutions.The results for the room measurements show that the indoor thermal comfort of the rooms, present long periods of discomfort namely in overheating. However, it was proved that the PCM application in one of the rooms lead to an overheating reduction of 7.23% representing a PCM efficiency of 35.49%. After the optimization process an overheating reduction of about 34% was attained by the use of PCM in one of the rooms. Regarding the economic analysis of the use of the PCM for cooling demand reduction, a payback time of 18years was attained.

A numerical study of building integrated with CaCl2·6H2O/expanded graphite composite phase change material

Integrating phase change material (PCM) into traditional building envelopes can decrease the building energy consumption and improve the indoor thermal comfort by enhancing the heat storage capability. In this work, CaCl2·6H2O/expanded graphite (EG) was employed to fabricate the PCM panels for building envelope as a low-cost PCM. In order to give full play to the role of CaCl2·6H2O/EG, its characteristic in structural insulated panel (SIP) was investigated numerically under different conditions. The enthalpy-porosity technique was used for modeling the solidification/melting process and it was validated by experiment. Temperature time lag, temperature decrement factor and energy saving rate were used to evaluate the dynamic thermal characteristics of the building envelope. The results showed that the density and thermal conductivity of PCM had little effect on the thermal performance of building envelope. However, the change of PCM panel thickness, building orientation, climate region and building construction would affect the phase change process of the PCM panels, which would have a certain influence on the room temperature. By analyzing the effect of CaCl2·6H2O/EG on the thermal performance of the building envelope under different influencing factors, it will provide effective guidance for the selection and use of PCM.

Outdoor Characterization of Phase Change Materials and Assessment of Their Energy Saving Potential to Reach NZEB

Phase change materials (PCM) are very promising materials for improving energy efficiency in buildings, especially in hot weather conditions. In spite of the growing attention paid to the integration of PCM into buildings, there are few studies on PCM evaluation under real operating conditions. This lack of data often does not allow accurate calibration and validation of building simulation models. This work aims to characterize a commercial PCM panel by RUBITHERM®. The panel was laid on the floor of a test box exposed outdoors, and the experimental data were used to validate a PCM software tool implemented in IDA Indoor Climate and Energy software. A reference office building model with characteristics prescribed by Italian regulations (STD) was provided with three PCM with melting points of approximately 21 °C, 24 °C and 26 °C, laid on the floor office. The building energy performance obtained was compared to the energy performance of a reference building prescribed by the new Italian building energy performance regulation (NZEB) for three cities in Italy (Trento, Rome and Palermo). The results showed that energy savings obtained from implementing PCM in the STD building were not sufficient to reach the NZEB reference value for all cities. Only the use of night ventilation was able to assist in reaching NZEB. PCM with a 21 °C melting point showed the best annual energy saving performance in all cities. Temperature range and temperature peaks experienced by PCM in the day/night cycle can explain the behavior of these materials in the various cities and seasons as latent and sensible heat storage systems.

Modeling and simulation of a photovoltaic/thermal air collector assisting a façade integrated small scale heat pump with radiant PCM panel

Integration of photovoltaic/thermal air-based systems into office façade retrofit projects using small scale decentralized heat pumps with low temperature short term storage using a radiant phase change material panel (RPCMP) is presented for a south facing office building perimeter zone. The concept can be applied in building façade retrofits, where both façade and mechanical systems are to be replaced. A numerical study is carried out for a case study building in Saskatoon, Canada. A numerical model is developed and the concept is theoretically compared to an all-air system for several consecutive design days. Electric power demand reduction of 14,5% for these design days can be achieved, if the façade integrated photovoltaic system would be supplying energy to the perimeter zone for heating and plug load applications. A reduction in heating coil heating power demand of 11.3% is achieved for the mentioned design days when compared to an all-air system.

Experimental and numerical investigations on the thermal performance of building plane containing CaCl2·6H2O/expanded graphite composite phase change material

CaCl2·6H2O/expanded graphite (EG) composite phase change material (PCM) with melting and freezing points of 27.11°C and 21.67°C and corresponding latent heat values of 118.7J/g and 115.7J/g was employed to fabricate the PCM panels for building application. The thermal performance of the test room equipped with the PCM panels at each position was evaluated by placing the room in an artificial climatic chamber. Compared with the reference one without the PCM panels, the test room equipped with the PCM panels exhibited much lower maximum temperature, higher minimum temperature, and reduced temperature amplitude, revealing the function of the PCM panels for reducing indoor temperature fluctuation. Furthermore, the investigation on the effect of the position of the PCM panels indicated that, the more inside position the PCM panels were placed at, the better thermal performance the obtained test room had. Moreover, numerical modeling was carried out to study the thermal performance of the PCM panels containing the CaCl2·6H2O/EG composite. It was found that the results from the numerical modeling agreed well with those from the experimental investigations. Base on the numerical modeling, it was found that the optimum thickness of the PCM panel was about 8–10mm, and the thermal performance of the CaCl2·6H2O/EG panels was better than that of the RT27/EG. It is revealed that the CaCl2·6H2O/expanded graphite composite PCM shows great promise in building energy saving.

A complex roof incorporating phase change material for improving thermal comfort in a dedicated test cell

The use of phase change materials (PCMs) as a building integrated thermal storage may contribute to improving building energy performances. This article focuses on the integration of PCMs in the roof with a non-ventilated air layer, in order to assess thermal performances of a dedicated test cell, especially for thermal comfort. An experimental equipment was set up at Reunion Island under tropical and humid climatic conditions. A mathematical model, based on the apparent heat capacity method is used to predict the actual impact of PCMs on energy consumption as well as thermal comfort.Once the comparisons are performed with simulations, the use of the psychrometric chart, Predicted Mean Vote and Predicted Percentage of Dissatisfied indexes, shows that in the tested configurations, thermal comfort can be improved. Indeed, as well as to enhance the thermal energy storage, the given configuration also reduce the solar radiation through the roof, due to the reflective properties of PCMs panel surfaces. A positive effect on inside air temperature of the full-scale experimental test cell is particularly observed.

A Study on a Novel Phase Change Material Panel Based on Tetradecanol/Lauric Acid/Expanded Perlite/Aluminium Powder for Building Heat Storage.

Phase change material (PCM) used in buildings can reduce the building energy consumption and indoor temperature fluctuation. A composite PCM has been fabricated by the binary eutectic mixture of tetradecanol (TD) and lauric acid (LA) absorbed into the expanded perlite (EP) using vacuum impregnation method, and its thermal conductivity was promoted by aluminium powder (AP) additive. Besides, the styrene-acrylic emulsion has been mixed with the composite PCM particles to form the protective film, so as to solve the problem of leakage. Thus, a novel PCM panel (PCMP) has been prepared using compression moulding forming method. The thermal property, microstructure characteristic, mechanical property, thermal conductivity, thermal reliability and leakage of the composite PCM have been investigated and analysed. Meanwhile, the thermal performance of the prepared PCMP was tested through PCMPs installed on the inside wall of a cell under outdoor climatic conditions. The composite PCM has a melting temperature of 24.9 °C, a freezing temperature of 25.2 °C, a melting latent heat of 78.2 J/g and a freezing latent heat of 81.3 J/g. The thermal conductivity test exposed that the thermal conductivity has been enhanced with the addition of AP and the latent heat has been decreased, but it still remains in a high level. The leakage test result has proven that liquid PCM leaking has been avoided by the surface film method. The thermal performance experiment has shown the significant function of PCMP about adjusting the indoor temperature and reducing the heats transferring between the wall inside and outside. In view of the thermal performance, mechanical property and thermal reliability results, it can be concluded that the prepared PCMP has a promising building application potential.

Fluid flow and heat transfer in PCM panels arranged vertically and horizontally for application in heating systems

The rectangular panel is within the most common geometries in phase change materials (PCM). Nevertheless, there is a lack of knowledge regarding how the arrangement (vertical or horizontal) and thickness affect heat flux and phase change duration. Such knowledge would be very helpful both in the design of PCM heat exchangers. This paper studies the behavior of the RT60 paraffin, Pr ≈ 330, phase change temperature between 53 and 61 °C; and the fatty acid Palmitic Acid, Pr ≈ 110, phase change temperature of 65 °C. Parametric studies analyzing the influence of: temperature of the walls (5 × 105 < Ra ≤ 2 × 106), phase change processes (melting and solidification), panel position and PCM thickness (aspect ratio1/20 and 3/20) are performed. The flow behavior is analyzed over time using velocity plots and volumetric liquid fraction contours. The formation of Bénard cells and their evolution is described. Free convection dependence of dimensionless string function and Rayleigh number is discussed. Free convection during melting for horizontal panels becomes very important and the mean heat fluxes increase up to twofold compared to vertical panels. For solidification, however, conduction becomes more relevant. The importance of both mechanisms is highlighted by calculating heat transfer rates.

Experimental study on the thermal performance of air-PCM unit

In the present research paper thermal performance of an air-phase change material (PCM) unit has been experimentally studied. The influences of the air inlet temperatures and velocities have been investigated on the charging/discharging time of the PCM panels, heating/cooling load and effectiveness over the phase transition. These parameters play a vital on determining thermal performance of an air-PCM unit. Air inlet temperatures of 34 °C, 36 °C and 38 °C and air inlet velocities of 0.6 m/s, 1.6 m/s and 2.5 m/s. have been studied. The increase of the air inlet velocity reduced the charging and discharging time, however not linearly. The time for the complete melting and solidification is substantially reduced when the velocity has been increased from 0.6 m/s to 1.6 m/s. The air inlet temperature has been proved to be most important factor affecting the discharging time. For lower air inlet velocity the cooling and heating loads achieve lower values but remain nearly constant over a longer period of time. The effectiveness reaches its highest values for the air inlet velocity of 0.6 m/s for the charging and discharging processes. It has been concluded that discharging time can be extended by reducing the air inlet velocity and making the technology more suitable for heating and cooling applications for the buildings. A simplified methodology is proposed for the analysis of the PCM charging and discharging process through the identification of the critical points as result of the heat transfer behaviour in the air- PCM unit.

Some aspects of energy efficient building envelope in high latitude countries

Nowadays, energy conservation in buildings is especially important for countries where high energy consumption in the residential and tertiary sectors causes the high energy intensity of the whole economy. This paper presents some idea of creating energy efficient building envelopes. The focus is on reduction of heat transfer through it. Different structures of external walls are analyzed. In high latitude countries walls should be characterized by high thermal resistance and high thermal capacity (good storage ability). In the paper traditional multilayer wall structures with specific paints on external wall surfaces are analyzed. Paints are characterized by different solar absorptivity. Two extreme cases of solar absorptivity of external wall paints (0.9 for the black paint and 0.1 for the black paint) have been taken into account to give completely different ability of the external wall surface for photo-thermal conversion (of solar radiation). Results show that in moderate or cold climates, if thick thermal insulation is applied as external layer of a building envelope, then the effect of solar absorptivity of a cover paint of external wall surface is not meaningful. In July, when daily solar irradiation is the highest, in the case of the black paint all day long there are small heat gains (about 2kJm−2 in average) with maximum in the night (3.1kJm−2). In the case of the white paint all day long there are small heat losses (about 2.3kJm−2 in average), with maximum in the middle of a day (2.7kJm−2). The effect of the solar absorptivity of the paint, that covers the external surface of the wall, can be seen, but it is very small and perhaps cannot be noticed by inhabitants. However, in the extreme summer weather conditions, i.e. very high irradiance level and high ambient air temperature, what have happened quite often in high latitude countries recently, the considered effect is more strong. Therefore, it would be good to apply envelope of a building, that can change “the skin” from summer to winter. Also modern structures with the Phase Change Materials (PCMs) are analyzed. In simulation study it was assumed that PCMs are applied in the form of light thermal mass panels that are integrated with the external wall structure. A mathematical model of dynamics of a building has been developed. In the paper stress has been put on energy transfer through walls of different structures. The model takes into account the influence of solar radiation on energy balance, including the availability of solar radiation on walls of different location (inclination and orientation). On the basis of the model developed simulation studies have been performed. Selected results of thermal behavior of some multilayer structures of external walls of a building have been analyzed. Through comparative studies some recommendations for creating building wall structures have been formulated. Results (presented in figures) show, how the temperature of a wall surface can increase because of the high solar radiation absorptivity of the surface paint. The temperature is especially high when a thick insulation is used. Because of the insulation the heat transfer through the wall is reduced significantly. If there is no insulation than the heat gained can be conducted (relatively easily) through the wall to the interior of a building, in consequence there are high heat gains in summer, and the temperature of the external wall surface is not high. It is evident that external surface temperature is not the basic parameter that determines the real heat transfer through a wall. Results show that in high latitude countries a wall structure for a standard building (used all year around) must contain thermal insulation as external layer. This is also true when the PCMs are applied in the form of light thermal mass panels. For high latitude countries the recommended structure of an external wall is following: thermal insulation (e.g. mineral wool) at outside (external layer) of thickness of 25cm and PCM thermal mass panel at inside (internal layer) of thickness of 1cm. Such wall structure assures full reduction of the ambient surrounding influence. An external wall made of a brick and a PCM panel does not have high enough thermal resistance (even if thermal capacity is high) to keep the room temperature at the required level. However, such structure could be recommended for the summer season, e.g. for summer houses in a moderate climate or high latitude countries, or for warm climate.

Experimental investigation of natural convection near a wall containing phase change material

An experimental investigation is conducted to characterize the natural convection heat transfer along panels which contain phase change materials (PCM). A dedicated configuration has been defined for this study. In this configuration, the natural convection heat transfer is triggered by a temperature scan in the ambient air. The temperature scan is responsible for the energy storage and release in the PCM panels. The corresponding experimental set-up was built and several melting and solidification tests were performed, with different values of the ambient temperature scan speed. The tested PCM panel is the Energain®wallboard by DuPont™. The system first reaches a stationary regime when the PCM is fully solid or liquid. During the stationary regime, the wall to air temperature difference and the convection heat flux are constant. The phase change causes an increase of these quantities. It is characterized by a first dynamic stage, a wall temperature slowdown/retrogression process, and a second dynamic stage. The two dynamic stages are well correlated to the PCM thermal characteristics. However, the temperature slowdown/retrogression phenomenon is unexpected. It consists in an extreme slowdown of the wall surface temperature evolution, which turns into a retrogression during the solidification experiments. The temperature slowdown/retrogression has never been observed before with PCM wallboards.

SOLAR THERMAL CONTROL OF BUILDING INTEGRATED PHASE CHANGE MATERIALS: AN EXPERIMENTAL SURVEY

In the present paper, we study experimentally the thermal behavior of phase change material (PCM) for thermal control of indoor applications. The experimental setup consists of two full scale identical concrete cavities, situated in Faculty of Sciences Ain Chock in Casablanca- Morocco (33°36'N, 07°36'W). The first cavity incorporates paraffinic phase change material with melting temperature of 22 °C and second cavity is built with alveolar bricks. The test cells are equipped by set of thermocouples and heat flux meters connected to data logger. Thermal analysis for the two cubicles was conducted. The results show that inner temperature swings decreases remarkably in the cavity with PCM with temperature minima 3 °C upper to the case without PCM. On the other hand, there is time shift between PCM cavity and the reference cavity temperature oscillations. The integration of the phase change material on the roof of the building reduces the temperature of internal walls as it has good thermal inertia. When PCM panel covered the roof, solar heat transmission is reduced. This significantly reduces the ambient temperature of the cell. This demonstrates the ability of PCM to increase the thermal comfort of buildings.

Modelling of an Active PCM Thermal Energy Storage for Control Applications

This paper presents the results of an experimental and numerical study focusing on the control-oriented modelling of an actively charged/discharged phase-change material (PCM) thermal energy storage (TES) system. The PCM-TES system consists of five layers of commercial macro-encapsulated PCM panels with an air cavity in its center. Air can flow through the cavity to charge/discharge the PCM panels. The PCM-TES was tested in an environmental chamber and its dynamic response was carefully monitored. A detailed fifth order thermal network finite difference model for the system is developed and verified against experimental results. The detailed model is then simplified to a 2nd order model for control purposes. A five-parameter equation is developed to model the storage of heat in the PCM. An average and maximum temperature difference of 0.8°C and 2.0°C, respectively, is achieved between the experiment data and that simulated by the detailed model. The second order model has an average and maximum temperature difference of 0.2°C and 0.9°C, respectively, compared to the detailed model. It is thus adequate for real time model predictive control of the system.

Experimental investigations on thermal performance of phase change material – Trombe wall system enhanced by delta winglet vortex generators

Experiments have been performed on the thermal behavior of a PCM (phase change material) – Trombe wall system with heat transfer enhancement by DWVGs (delta winglet vortex generators). PCM (CaCl2·6H2O) slabs were attached on the gap – side wall surface to increase the heat storage. Delta winglet VG pairs (attack angle β = 45°, ratio of length to height l/h = 2) were arranged on the surface of PCM panel to enhance the air side convective heat transfer in the gap. The VG height, pitch and locations were also evaluated. The results showed that the delta winglet VG pairs really enhanced the heat transfer rate at the surface of PCM panel during both the charging and discharging processes. Accordingly, the gap air flow rate and heating rate to the room with a single row of delta winglet VG pairs are 28.5% and 39.4% higher than the case without VGs. Delta winglet VG pairs with height of 30 mm, front edge pitch of 2 mm, lateral spacing of 225 mm and vertical spacing of 340 mm give best thermal performance under present conditions. The results indicate the advantages of using longitudinal vortex generators to improve the performance of PCM – Trombe wall systems for passive solar heating.

PCM Thermal Energy Storage in Buildings: Experimental Study and Applications

Abstract The study aims at analyzing the performance of Phase Change Materials (PCMs) in residential housing for different climates. This paper presents the results of an experiment performed in the Concordia University Solar Simulator and Environmental Chamber research facility (SSEC, Montreal, Canada). PCM boards were embedded on the back wall of a test hut placedin the climatic chamber. Several experiments were performed to explore the potential for verification of the proposed analysis and to produce enough data to perform model calibrations. Results show a strong increase in the apparent thermal inertia of the room allowing for a reduction in daily temperature fluctuations in the test hut. Simulations were carried out by means of a calibrated EnergyPlus model to broaden the analysis in both a cold Canadian climate and in a Mediterranean temperate climate. Other configurations for the setup environment were studied to simulate the issues of very hot summers in Mediterranean climate. The different configurations ended up with mixed results for the two locations analyzed: the maximization of the solar gains and its storage in a high density multiple layer PCM wall is the better configuration for the cold climate analyzed, while its performance is non optimal for hot climates where the “emulation” of high thermal mass walls by PCM in lightweight structures requires a different positioning of the PCM panels.

Development of Composite PCMs by Incorporation of Paraffin into Various Building Materials.

In this research, we focused on the development of composite phase-change materials (CPCMs) by incorporation of a paraffin through vacuum impregnation in widely used building materials (Kaolin and ground granulated blast-furnace slag (GGBS)). The composite PCMs were characterized using environmental scanning electron microscopy (ESEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Moreover, thermal performance of cement paste composite PCM panels was evaluated using a self-designed heating system. Test results showed that the maximum percentage of paraffin retained by Kaolin and GGBS was found to be 18% and 9%, respectively. FT-IR results show that CPCMs are chemically compatible. The phase-change temperatures of CPCMs were in the human comfort zone, and they possessed considerable latent-heat storage capacity. TGA results showed that CPCMs are thermally stable, and they did not show any sign of degradation below 150 °C. From thermal cycling tests, it was revealed that the CPCMs are thermally reliable. Thermal performance tests showed that in comparison to the control room model, the room models prepared with CPCMs reduced both the temperature fluctuations and maximum indoor center temperature. Therefore, the prepared CPCMs have some potential in reducing peak loads in buildings when applied to building facade.

Composite of Coal‐Series Kaolinite and Capric–Lauric Acid as Form‐Stable Phase‐Change Material

AbstractA composite phase‐change material (PCM) consisting of a binary organic mixture of capric–lauric acid and coal‐series kaolinite (Kc) as was prepared by vacuum impregnation. Dimethyl sulfoxide was used as intercalation agent to increase the interlayer Kc space, enhancing the storage energy density of the composite PCM. Capric (CA) and lauric (LA) acids were inserted into the interlayers of the Kc intercalation complexes (I‐Kc). The chemical structure and thermal properties of the composite PCM were characterized in detail. The thermal performance of the corresponding cement paste composite PCM panel was also evaluated. The latent heat of the CA–LA/I‐Kc was 42.36 J g−1 at a melting temperature of 16.96 °C at a CA–LA content of 36.93 %. The melting temperature of the composite PCM changed to −0.33 °C and the latent heat storage capacity to 0.22 J g−1 after one month of thermal cycling, which shows the excellent thermal reliability of the composite PCM and potential application for thermal energy storage in energy‐efficient buildings.

Establishment and experimental verification of PCM room's TRNSYS heat transfer model based on latent heat utilization ratio

The aim of the present work is to set up an apparent specific heat capacity phase change heat transfer model and a new TRNSYS component (Type272). A PCM (phase change material) room model is established by combining Type272 and some TRNSYS components (Type 56, 109, 16, 69, 33, and Type 65). The latent heat utilization ratio (α) is proposed in Type272 which treats the melting and the solidification process, respectively. To validate the new model, a full-scale experiment room installed with PCM panels is built, and two different working conditions (passive/active cool storage condition) are set up. It is found that both the trend and the simulation data of the model are agreed well with the experiment results. In the two different conditions, the MREs (mean relative error) between the simulated and the measured data are less than 3% and 7.59%, respectively, and the consistent match degree lies between 90.10% and 98.81%. The new model, with simplicity, adaptability and practicality, can accurately simulate indoor temperature and the surface wall temperatures. Our work provides an effective tool to optimize the design of the PCM room by simulating different kinds of PCMs, locations, and different combinations with cold and heat source.

Numerical study on the thermal performance of building wall and roof incorporating phase change material panel for passive cooling application

The phase change material (PCM) used in the building envelope can decrease the building energy consumption and improve the thermal comfort by enhancing the thermal energy storage capacity of the wall and the roof. In this research, two new PCM systems, i.e., PCMOW (capric acid contained in the panels installed on the outside surface of building) and PCMIW (capric acid and 1-dodecanol contained in the panels installed on the inside surface of building), have been developed numerically. The main study constitutes four parts: (1) the model and its validation; (2) the analysis on temperature variations of the wall and the roof; (3) the analysis on the internal temperature developments of the wall and the roof; (4) the study of thermal energy saving. A mathematical model and its corresponding numerical solution were presented. Relative error analysis inclusive of maximum and average errors and Bland–Altman analysis were employed for validation. It is found that the numerical simulation achieved good validity. The theoretical analysis of temperature variations of the walls and the roofs for the PCMOW, PCMIW and reference rooms has been conducted. Then, the internal temperature developments of PCMOM and PCMIW systems were analyzed to reveal the operation of the PCM panel in the wall and the roof. This study also explored the analysis method of thermal energy savings for the two PCM systems to maintain the indoor temperature within thermal comfort zone.

The Ekihouse: An energy self-sufficient house based on passive design strategies

The Ekihouse is an industrialized solar house prototype, designed and developed by the University of the Basque Country for the SOLAR DECATHLON EUROPE 2012 competition held in Madrid (Spain). The building design strategies are based on the full integration of active—passive solar technologies and passive design criteria in order to achieve an energy self-sufficient proposal, providing high quality of life to its occupants. Despite its intentionally small surface area (54.6m2), the house can be adapted to suit a wide range of lifestyles thanks to its flexible, multifunctional open plan design that can be visually and physically expanded outdoors by removing the northern and southern glazed façades (PVC joinery and 0.9kW/hm2°C glass). For ease of transportation and assembly, the Ekihouse consists of a modular CLT structure system (two 12.60m×3m modules) that supports the photovoltaic roof (10kWp) which functions as a canopy to protect the southern facade from direct solar radiation thereby reducing overheating problems in the building interior. In order to control the indoor temperature, PCM panels are mounted in the ceiling. When passive strategies are insufficient in extreme conditions, the house is also equipped with a ventilation and air-conditioning system that allows a 90% energy recovery. Furthermore, an outdoor evaporative cooling system helps lower the ambient temperature by up to 4°C. A rain and grey water treatment and purification system is also installed. The operation of all this active technology is controlled by an optical domotics system.