When most folks think about energy efficiency and lighting, it's the spiral-shaped compact-fluorescent light bulb (CFL) that comes to mind. Granted, CFLs use 75% less energy than their incandescent counterparts and last 10 times as long, and according to Natural Resources Canada, by using only energy-efficient lighting systems with ENERGY STAR qualified bulbs and matching fixtures, you can cut up to $150 from the average $250 annual residential lighting expense. But whether you're building a new home or renovating an existing one, it's important to think beyond the bulb.
That's why incorporating some general lighting design principles into your next project can help create a space that's lit beautifully and efficiently without sacrificing functionality or ambience. In many cases, it's also worthwhile to consult a lighting design professional who's on top of the latest lighting technologies, trends and techniques.
"The goal [of a lighting design] is to support the function of the space, create a certain atmosphere and to achieve this goal spending the least possible energy," says Galina Zbrizher, IALD, LC, principal of Vancouver, B.C.-based Total Lighting Solutions. "It's not about the bulb. It's about quality of life. It's about understanding the function and then designing lighting systems to serve this function using available technologies together: lamps, fixtures and controls together."
The first step is to look at the existing light sources to decide what can be accomplished without even flipping a switch.
"When I get involved a lighting design, the first thing we talk about is daylight," says Joseph Scott, IALD, LC, PLDA, lighting consultant with TRIPPED ON LIGHT design inc. in Texada Island, B.C., as the most energy-efficient system is the one that's not turned on. "Once we've exhausted every possibility there, only then do we talk about electric lighting."
Today's energy-conscious designers opt for multiple lower-brightness sources of light over a single high-wattage source to reduce glare and make the space feel more pleasant.
"A general rule of thumb is that installing multiple, smaller wattage, less-bright fixtures will result in a better environment in comparison to installing one high-wattage, very bright fixture," says Zbrizher.
Evaluating how homeowners will use the space informs where light will be needed and what techniques will get the desired effect.
"To get a nice effect at home, you have to have multiple layers, such as decorative, task and ambient lighting," says Zbrizher. "The more layers you have, the richer the space is perceived."
For example, while ambient lighting provides general illumination for everyday tasks (think traditional ceiling domes), task lighting provides directed light for particular activities, such as concealed under-cabinet lights for kitchen food preparation or a pendant light hanging over a table. When you optimize the use of task lighting, you can reduce the ambient light elsewhere.
"Gone are the days of lighting everything, everywhere all the time," says Scott. "We can't afford that anymore, and it's not really desirable."
Having decided where and how much light is needed, the next step is to decide what the source of the light should be, says Scott, whether it's a halogen, LED, incandescent or fluorescent bulb. (For more information on bulbs, please see the Lowe's Light Bulb Buying Guide.
That means matching the quantity and quality of light provided by a certain lamp to a particular application. So while a CFL works well when you want to create a glow in a pendant lamp with a translucent shade, a linear fluorescent is perfect for under cabinet lighting and uses 30% less energy.
"Once we've decided the source or bulb, then it would be, 'what kind of fixture could provide it that uses that kind of bulb?' Every task in every room would have a different answer," says Scott.
But an energy-efficient lighting design doesn't end with fixtures and bulbs: it's critical to remember the controls.
"Controls in my opinion are the most undervalued, underused and yet one of the most effective tools to save energy," says Zbrizher. "They reduce energy consumed over time, the true measure of energy efficiency."
Occupancy sensors, timers, dimmer switches and for retrofits or new home construction, sensors that automatically dim and raise the lights according to the amount of available daylight all help save the planet and your client's wallet.
"You'll save more money if you have better controls than you will if you're trying to get energy-efficient light fixtures," says Scott.