Advanced Lighting For Retail

Transcription

1 Advanced Lighting For Retail SPECIALTY MARKET APPLICATIONS Café This specialty market lighting application module presents guidelines for energy effective lighting in a café. However, these strategies can be applied to any space with similar lighting requirements, whether part of a larger store or in an independent boutique storefront. The ambient lighting strategy should support the function and aesthetic of each store area. In the general sales area, ambient light levels may be relatively higher and more uniform. In specialty areas, lower ambient light levels allow for more accent light on products, creating focus and attracting attention to the products. The ambient lighting should provide a soft quality of light upwards into the exposed structure above. This indirect light provides a sense of the entire volume of the store. By illuminating the structure, it will not become either too dark or too bright. Instead, it would remain fairly neutral in the luminous environment and not take away focus from the merchandise. Another benefit of this uplight component is to help reduce the potential glare from the skylights by brightening the ceiling. To help lower the energy consumption of the store, it is important to select luminaires for the ambient lighting system that can be integrated into the control strategy. Compact fluorescent and linear fluorescent luminaires offer both dimming and on/off switching options for energy saving controls. Dimming daylight controls are preferred to provide a smooth and imperceptible variation of electric lighting that does not disturb customers.

2 Approach CONCEPT Lighting Concepts for the Café: Specialty Markets are known for the experience of shopping, set up to feel like an outdoor market of multiple vendors providing fresh artisan products. Lighting equipment is used to enrich this experience and to help identify the differing departments. Lighting details and quality reinforces the high end appearance of the Café and the store. Ambient light levels are lower here than in the other specialty market areas. The dimmer area invites customers to take a break from shopping and enjoy coffee or pastries. Decorative luminaires provide much of the ambient light while soft accents highlight signage and displays. Architectural methods for identifying this store area often include changes in ceiling height and different interior finishes. Enhance the department identity with visual cues such as decorative luminaires and lower luminaire mounting heights. CRITERIA Horizontal illuminance, color temperature, and color rendering on merchandise displays should be a high priority. Horizontal Illuminance: 10-20fc Uniformity: 5:1 max/min Lamp correlated color temperature: 3500K-4100K Color Rendering Index: 80 or greater Refer to IESNA RP-2, Lighting for Merchandise Areas and IESNA Lighting Handbook Chapter 10 for more detailed information. 2 Advanced Lighting for Retail

3 Strategy DAYLIGHTING Café seating may often be adjacent to perimeter windows. Lighting in these locations can be turned off entirely during the day. Toplighting can be introduced with tubular daylighting devices (TDD) but very little ambient lighting is required. Avoid over lighting such that the accent and decorative lighting is overpowered. LUMINAIRES A Pendant-mounted CFL luminaires with a translucent globe provide low-glare decorative ambient lighting for the café seating area. Their lower mounting height continues the visual cues established with the lowered soffit. B Recessed CFL downlights in the lowered soffit provide general lighting on tables that are not near windows or illuminated by the decorative pendants. C Recessed CFL wallwashers increase the surface brightness and provide a comfortable, no-glare, ambient light along the perimeter of the space. They can also be used to highlight signage or wall displays. A B C D E LUMINAIRE SCHEDULE FOR RETAIL SPECIALTY MARKET APPLICATIONS Pendant-mounted decorative globe mounted with bottom of luminaire at 8'-0" AFF Diffuse distribution White opal glass diffuser and polished aluminum suspension Minimum Luminaire Efficiency: N/A Recessed compact fluorescent downlight 6" aperture; 18 gauge steel housing with one piece spun aluminum reflector Minimum Luminaire Efficiency: 37% Recessed compact fluorescent wallwasher 6" aperture; 18 gauge steel housing with one piece spun aluminum reflector Minimum Luminaire Efficiency: 55% Pendant-mounted compact fluorescent industrial open lowbay downlight, bottom of luminaire mounted at 10'-0" AFF Housing made of spun matte anodized aluminum Minimum Luminaire Efficiency: 47% (2) 32 watt compact fluorescent lamps Pendant-mounted decorative luminaire mounted with bottom of luminaire at 8'-0" AFF Direct / indirect distribution Ribbed acrylic cylinder Minimum Luminaire Efficiency: N/A (2) 28 watt T5 fluorescent lamps (F28T5/835/PM Low Mercury) CAFE System Input Watts: 36 Ballast factor: 0.98 System input watts: 36 System Input Watts: 36 Luminaire wired for two circuit operation for dual switching, allowing both lamps on, one lamp on, or both lamps off System Input Watts: 66 Mean Lamp Lumens per Watt: 57 Luminaire wired for two circuit operation for dual switching, allowing both lamps on, one lamp on, or both lamps off Ballast Factor: 1.0 System Input Watts: 66 Mean Lamp Lumens per Watt: 70 D The CFL low bay luminaires create the ambient lighting for the higher ceiling seating 3 Advanced Lighting for Retail

4 area. Their suspension creates a lowered perceived ceiling that aligns with the soffitted portions of the space. These visual cues identify the café as a separate area and create a more intimate gathering space for the patrons. E Decorative fluorescent pendants along the windows continue the visual cues of the café and reinforce the identity of the space, even from outside the store. MAINTENANCE ISSUES Compact fluorescent lamps have long lives and are readily available. They reduce energy and maintenance as compared to tungsten halogen. It is best to stock the fewest different types of lamps possible. Luminaires should be cleaned on a regular basis to avoid loss of light from dirty surfaces. Controls DAYLIGHT DIMMING Dimming ballasts and photo sensors will dim luminaires near skylights and windows when sufficient daylight is available. The gradual dimming control avoids a sudden change in light output that may be noticeable to customers. Demand reduction can also be accommodated. EVENING / NIGHTTIME DIMMING Dimming ballasts will dim luminaires during evening and nighttime hours when customers eyes are adapted to less light. Demand reduction can be accommodated. AFTER HOURS SWITCHING During stocking hours, when less light is needed, light levels can be reduced. This can be accomplished with dimming, bi-level switching, or keeping lights at full brightness only in occupied zones. OCCUPANCY SENSORS During low activity times, occupancy sensors can raise lighting levels only in occupied areas. Other luminaires can dim the lighting by zone. 4 Advanced Lighting for Retail

5 Design Parameters APPLYING THIS MODULE TO YOUR PROJECT The design modules shown in the ALG are intended to serve as examples of best practices in lighting for common spaces with typical conditions. They provide a starting point for design teams, but are not intended to replace the design team or process. PARAMETERS USED TO DEVELOP THE DESIGN This lighting design was developed and modeled with the following parameters and assumptions. If these factors are different in your space, it will be necessary to make modifications to address actual conditions. 30' Open Truss Ceiling 9' soffit Floor Reflectance: 20% Wall Reflectance: 50% Wall above soffit: 75% Ceiling Reflectance: 75% Light Loss Factor (LLF) for fluorescent sources: 0.65 Light Loss Factor (LLF) for compact fluorescent sources: 0.75 Light Loss Factor (LLF) for metal halide sources: 0.75 Quicktips The social atmosphere of a café allows for lower luminaire mounting heights, identify a visual hierarchy to keep it from becoming chaotic. The perimeter window lights should be controlled separately from the rest of the store lights. Use as few different lamp types as possible, especially when specifying decorative luminaires. This will reduce maintenance and lamp inventory. Dirt will probably be an issue with all of the suspended equipment in the space, especially those luminaires with decorative elements. The lighting should be cleaned with a damp cloth at least once a year. For more advanced lighting design information for specialty markets including inspiration, daylighting and ambient, accent, perimeter and decorative lighting, go to: php?specialty-market Critical factors that will require modifications from this design include room dimensions, spacing and height of the gondolas, colors and reflectances of the surfaces, and the mounting height of the luminaires. About New Buildings Institute ALG Online is one of the design guides offered by New Buildings Institute (NBI) through its Advanced Buildings suite of tools and resources. NBI is a nonprofit organization working to improve the energy performance of commercial buildings. The organization works collaboratively with commercial building market players governments, utilities, energy efficiency advocates and building professionals to remove barriers to energy efficiency, including promoting advanced design practices, improved technologies, public policies and programs that improve energy efficiency. NBI works nationally with offices located in White Salmon, Seattle and Vancouver, Washington. Visit us for more information about New Buildings Institute at newbuildings.org, ALG Online at algonline.org and Advanced Buildings at advancedbuildings.net. 5 Advanced Lighting for Retail