Glossary
System Performance | System Description | Case Study
 
 
RETROLux Technology
Part of:  Light Guiding Venetian Blinds  

 
Made by:  Retrosolar   
Used by: Koester Lichtplanung  Gatermann + Schossig 

The RETROLux Louver System’s shaped louvers consist of two components, one used as a retro-reflector of high.angle summer sunlight so as to block out heat penetration, and the second as a light-shelf for improved daylight deflection to the inside, while providing glare protection.
 


System Performance


Retro reflecting louvers improve upon conventional Venetian blinds by providing protection against low-angle winter sunlight and high-angle summer sunlight, thus avoiding both overheating and glare issues without darkening the interior, as the blinds are usually kept open (they must only be closed when angles of incidence are below 25º). It is indeed possible to keep the slats in horizontal position by combining mirrored surfaces with a specific designs of the slat’s profile. This provides a good visual transmission through the blinds (≈74% of the glazed area for internal use, and  ≈59% of the glazed area, for external use) and a good diffuse distribution of light inside. For the exterior application, each RETROLux louver has two parts, one with a sun control function, vertically curved, and the second with a daylighting function, horizontally curved. For the interior application, the louvers’ retro-reflection component have a different shape, close to a w profile. To control sunlight while letting daylight penetrate, RETROLux louvers offer a zoned configuration of the slats: the upper louvers (above 1.9m)-RETROLuxO, have a flat angled second component, to bring light deeper into the room, and the lower louvers (below 1.9m)-RETROLuxU, have a more steeply angled second component to guide light towards the ceiling. For a more advanced lighting analysis and project specific results, we recommend using the Lightsolve program (under development).

Performance data for all systems in the same category. Comparison to systems in other categories, selected through the matrix filtering process.

 

System Description

RETROLux louvers are made of extruded aluminum, bent into concave or convex shapes, with mirrored top surfaces (reflectivity goes from 82%  to 9%, depending on the finish) and their undersides coated with light grey enamel (reflectivity of 86%). These louvers can be installed on the interior or the exterior of the glazing. Available sizes are 50mm in width, and of customized length. The louver spacing is  approximately 29mm. The blinds can be gradually adjusted (lifted, lowered or twisted), which allows multiple louvers to be moved simultaneously, either individually or in groups, depending on the current sun angle and lighting conditions. If necessary, it is also possible to completely open the louvers in both areas to provide free vision, the response time for the up/down switch being 4 seconds. The system can be manual and automatically operated via a switch or remote control. The system can be installed vertically and within roof systems (for angles greater than 45 degrees). Energy savings are expected to come from reducing cooling and electric lighting loads.

RetroSOLAR  www.retrosolar.de

 
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