Optimization and Innovation in BIPV Design. Source – Team X-House
Team SCUT x CSCEC won the overall contest, plus 9 other sub-contests, at the Solar Decathlon Middle East 2021. It is a unified team that designed, built and operated a zero energy, sustainable and innovative solar building in Dubai, a prototype of the house of the future: X-House.
The BIPV project includes an integrated photovoltaic roof system and an integrated photovoltaic enclosure. These two systems are used simultaneously as shading and power generation components, helping the X-House to achieve zero energy consumption, while insulating the house from the hot Middle East sun and reducing energy losses.
The roof-integrated photovoltaic system is the energy source of the X-House. To counteract the effects of the weather, it is inspired by the past through an atrium and a wind catcher. The entire roof is designed with photovoltaic modules acting as a double roof system. The ventilation layer significantly improves the performance of the photovoltaic modules by preventing overheating. Sunlight is reflected by the Radi-Cool film (with 91% solar reflectance) on the lower roof which provides 30% more radiation for energy generation by the bi-faced photovoltaic modules and thus improves the performance of the photovoltaic system. X-shaped climate control plates are electronically activated and are placed all around the house, this system can switch from one state to another:
1) Good weather – the plates amplify the wind flow to the rooms to provide comfort.
2) Warm weather – the plates open and the wind flows through to cool the photovoltaic modules.
3) Windy weather – with all plates and shutters closed, a buffer area is created that is protected from sand and dust.
X-House opted for Yingli solar’s most advanced product: YL405CG2536F-2 1/2. These modules use crystalline silicon PV cells of the PANDA type. The double-sided photovoltaic modules can achieve an annual energy production of approximately 27 MWh (26811 kWh), which is four times the annual consumption of this building. Based on the outcomes during the competition period from 13 to 23 November, X-House consumed 362 kWh and generated 645 kWh, which shows that the energy production of X-House is 1.8 times the energy consumption in the late autumn period.
BIPV GREEN WALL
The enclosure is modular and multifunctional. Each module consists of three components: frame (prefabricated 400 x 400 mm UHPC – Ultra High Performance Concrete), front panel and inner panel. Two types of products were selected for the X-House – one is a dark black enameled coloured product from GAIN SOLAR with zero light transmittance and a black glass structure, and the other one is a cadmium telluride film module from Advanced SolTech Renewable Energy, with 70% light transmittance. The internal panels can be combined with « green elements » or connected to various DC appliances. Customisation options ensure a variety of uses and applications.
Roof BIPV. Source: Team X-House
Green wall BIPV. Source : Team X-House
Third prize winner in the BIPV contest – jury evaluation (Dr. Arch. Francesco Frontini and Dr. Arch. Cristina S. Polo López)
The project X-House integrates BIPV modules both in the horizontal roof and as a vertical shading enclosure element) around the house. The construction is very well built and reveal the great effort of the team to achieve the task. Starting from the top of the house, the double-layer roof is made by high efficiency of double-sided PV panels (bi-facial) and with laid Reflective Radiative-Cool film, which cools the roof and helps to enhance the production of renewable energy from the back of the modules. The construction is perfectly integrated with both the building energy system and the interesting cooling system underneath that is made of movable elements (as a re-interpretation of traditional cooling towers). The shading element (the vertical enclosure) around the house is made of modular components with multifunctional purposes. The enclosure design is achieved through white 3D printed and easy to assemble frames that integrate two different BIPV technologies: black crystalline solar cells for the opaque element and semi-transparent CdTe thin-film cells for the transparent one. The BIPV elements supply enough energy (5V each) to power the appliances to improve outdoor comfort. The design is well integrated with the architecture of the house contributing to a pleasant ventilation of the outdoor space and providing the appropriate privacy for the house occupants.