The electrical industry has done a credible job of developing energy-saving lighting products that have found wide use in the commercial, institutional, and industrial markets. However, except for compact fluorescent (CFL) lamps, it has not made appreciable inroads in the residential market. Given the improved color of the triphosphors and the inherent lumen-per-watt efficacy of CFLs, manufacturers began to work on ways of tapping the residential market some years ago. The linear tube was bent, first into a circular, then into a U-shape. Recently, further bends and twists have been added, producing many different CFL shapes. But, we know that consumers generally have a negative concept of fluorescent lighting, preferring not to install these lamps in their home, because they believe the results would be poor or institutional in appearance.
Nevertheless, the increased residential use of full-size fluorescent lamps and control equipment presents a great opportunity to reduce electric energy use. Thus, a recent survey relating to lighting for new home construction is newsworthy. In 1994, as part of an annual showcase of new homes sponsored by the Home Builders Association of Rochester, N.Y., two nearly identical homes were built to provide a side-by-side demonstration, comparing the usual residential lighting with an energy-efficient design. The two townhouses were typical middle-income structures, with a starting price of $119,000, and the furnishings for both were chosen by interior decorators selected by the builder.
While one house had conventional lighting, using a typical pallet of hard-wired and portable lighting products that cost about $1950, the other had energy-saving lamps, luminaires, and controls that cost about $3250. This figure includes additional wiring, materials, and labor for site-built luminaires, such as valances and soffits, crown moldings, and cabinet trim.
With a calculated $183 savings in annual operating expenses (mostly power costs) the simple payback on the $1300 additional expenditure is seven years. Amortized over a 25-year mortgage at 8% interest, the annual cost increment would be about $120. Subtracting this from the $183 estimated operating cost saving still yields a net annual savings of $63.
In the living room, a site-built valance provides dimmable direct/indirect lighting. It is supplemented with a torchiere lamped with a screwbase compact fluorescent and a halogen PAR downlight accent over the fireplace. Fluorescent striplights mounted on top of the kitchen cabinets create smooth indirect lighting. Halogen PAR downlights with decorative trim rings and fluorescent undercabinet lights provide uniformly high light levels on the countertops.
A ceiling-mounted wooden soffit conceals fluorescent striplights mounted above the bed. These graze the walls, creating good illumination for reading as well as soft ambient light throughout the room. Recessed adjustable halogen PAR accent lights highlight artwork on either side of the dresser. The dining room chandelier uses a dimmable halogen. A lamp and a recessed adjustable halogen PAR lamp accent a floral arrangement. Compact fluorescent vanity lights are used on both sides of the bathroom mirror. Door jamb switches control closet lights, and manual ON-AUTO-OFF motion sensors are used in the small bedroom and laundry room.
Served by electronic ballasts, all of the fluorescent lamps have a high color rendering index (75 CRI or higher) and a warm color temperature (3000K) to blend well with the incandescent lamps.
With 790 visitors touring the two homes, the survey showed that 97% of the people said they would be willing to pay more for the energy-efficient home, and half of them would be willing to spend $825 or more for similar equipment to gain some of the design objectives. These objectives were: Visual effectiveness, flexibility of use, practical initial costs and annual operating costs, and ease of maintenance. Other benefits: Not having to supplement lighting with table lamps requiring electrical cords strung behind furniture.
A paper describing this study - sponsored by the New York Energy Research and Development Authority and Rochester Gas and Electric Co. - was given at the 1995 IESNA Annual Conference by two members of the Lighting Research Center (LRC). As Russell P. Leslie, AIA, IESNA, one of the presenters and the director of the LRC, located at Rensselaer Polytechnic Institute, Troy, N.Y., notes: "The success of the energy-efficient townhouse demonstrates the usefulness of having model lighting designs, or 'patterns,' that show good lighting installations. Electricians, builders, and home owners themselves with limited technical knowledge often select residential lighting, but they could do better if they knew how."
Consequently, the LRC has developed The Lighting Pattern Book for Homes, the first in a growing resource of generic lighting pattern books: The Electric Power Research Institute is developing a controls pattern book; the LRC will soon release The Outdoor Lighting Pattern Book; and manufacturers are developing office lighting pattern books. More lighting patterns will be available in the future.
Lighting is not just something by which to see anymore. Today, lighting provides an environment for many activities.