Low energy architecture through passive curtain walls. Solar evaluation of passive curtain wall technology in hot summer climates.

ESTEVES, ALFREDO; GANEM, CAROLINA

Renewable Energy 2003

Sovereign Publications Ltd

Lugar: London; Año: 2003; p. 86 - 88

A series of sustainable technologies that contribute to the reduction of energy consumption in the built sector are already known. The majority of these strategies are applied on the envelope of the building. Between the strategies that can be used in the summer season in hot climates, the first measure is to avoid heat gains, designing proper protections and preventing solar energy gain through transparent non-insulated windows. Even though this protection strategy is highly recommended; a coating technology called curtain wall, an integral alluminium-glass façade, is widely spreading in refurbishment and recycling projects; as well as in new buildings in all type of climates. This technology is used greatly on high storey construction, in which the building has a great amount of surface at sun exposure. The reflective glass sheathes sending a beam of reflected sunlight to the neighborhood below. A computer programme has been developed with the methodology for solar radiation on tilt surfaces. This has served to know incident solar radiation in each façade with different orientation. With the values of the incident solar radiation and the values of the transmittance, the values of the solar radiation that reach the interior of the building can be calculated; and that later on the air conditioning equipments will have to take and remove. Results indicate that the generated situation by the incorporation of curtain wall in buildings produce a high impact for the case of being applied to cities with hot and dry climates such as the central west region of Argentina, where the prevalence of sunny days makes it very difficult to overcome discomfort situations using passive techniques. The impact could only be reduced using the appropriate protections for each orientation, therefore, permanent and temporary solutions for each expression and orientation case are given.