Energy Source Builder

Lighting Patterns Promote Efficiency

Most residential lighting design is done by building designers and home owners, who don't usually have the knowledge or skill to make the best lighting decisions. That's one reason that the lighting scheme for many houses tends to turn out the same: a circular diffuser in the middle of the ceiling.

Lighting is a highly technical field and one that's changing rapidly. Even the terminology passes most people by. Bulbs are called lamps, fixtures are called luminaires. The humble on-off switch, while still widely used, is being edged out by dimmers, motion sensors and home automation systems.

One good way to keep up with the latest ideas in lighting is to consult a copy of The Lighting Pattern Book for Homes. In 221 pages, authors Russell Leslie and Kathryn Con-way give an excellent reference on energy efficient lighting design.

Designs

About one-third of the book presents room-by-room lighting designs--147 designs in all. For each room type there's at least one typical design. It's based on the room designs s normally found in low- to mid-priced homes and manufactured homes. For each typical design, the book describes several alternatives that provide equal or better lighting and save energy. Alternatives fall into three categories: replace lamps, replace controls and replace luminaires. Any of these alternatives could apply to remodeling or new construction. In most cases, replacing the luminaire offers the greatest efficiency improvement. The design below was reprinted from the book.

A graph compares the cost of the typical design with each of the alternatives. Costs include energy and lamps. In the graphs, energy costs are assumed to be 10¢ per kwh. You can easily convert this to your local rate. (For example, if your rate is 5¢/kWh, multiply by 0.5. If your rate is 14¢/kWh, multiply by 1.4.)

Technical Information

Other chapters describe the various types of lamp technologies, luminaires, controls and economics. This information is detailed, but easy to understand. For example, the description of each lamp (incandescent, halogen, fluorescent, etc.) contains a table of specifications that includes: lamp life, light output, color temperature, color rendering index and typical cost. Ways to use each lamp also are described. Products and manufacturers are not mentioned by name.

Sample Design

Typical	Alternative

Annual Operating Cost at $0.10 per kWh