Light Well: Indoor and Outdoor Lighting Ideas for the Home

Enlarge Image Image Gallery "Green Lighting" is a do-it-yourself guide that makes it easy to upgrade residential and commercial lighting to reduce costs and environmental impact while maintaining the quality of the lighting. Photo Courtesy McGraw-Hill

The following is an excerpt from Green Lighting: How Energy-Efficient Lighting Can Save You Energy and Money and Reduce Your Carbon Footprint by Brian Clark Howard, William J. Brinsky and Seth Leitman (McGraw-Hill, 2011). The excerpt is part of Chapter 8: Lighting Best Practices and Daylighting. 

While it’s possible to choose a lighting scheme based on detailed calculations of square footage, bulb output in lumens, angles of light, and other factors, it’s also true that lighting is highly intuitive. For the most part, it’s relatively easy, and affordable, to change the lighting in rooms. Simple adjustments include swapping out bulbs and shades, adding or subtracting floor lamps, or changing your curtains. In other cases, more intensive changes may be needed, such as rewiring fixtures or adding a window or skylight to let the free sunshine in.

In general, it’s best to light rooms with a number of sources rather than from a single lamp, whether it is an overhead or based on the floor or wall. By using several sources, you help to reduce glare and harsh shadows and have more flexibility.

Let’s take a look at some ways to maximize comfort and productivity, as well as energy savings, in your home or business.

Indoor Lighting Strategies 

Here are some general tips for smarter, more efficient lighting:

• Use focused task lights as much as possible, reducing the need for general ambient lights.
• Use the lowest-wattage bulb you can for a given task.
• Turn off lights when you aren’t using them; sensors, timers, and other controls can help.
• Use light colors on walls, which will reflect more light and reduce your need to generate it.
• Maximize the use of windows and skylights, which is called daylighting.
• In retrofits and new construction, make sure that all lighting meets, or exceeds, applicable codes. This will improve safety, preserve your property value, maintain efficiency, and reduce your liability and risk of fines.

Know When to Turn Off Your Lights 

Naturally, the surest way to save energy with lighting is to reduce the length of time that it is switched on. However, the actual cost-effectiveness of when to turn off lights depends on a number of factors, chiefly the type of light and the price of electricity. Turning off incandescent lights starts saving money after just a few seconds because they don’t require much to start up. Also, since incandescents are not appreciably degraded by turning them on and off, they can be switched on and off frequently without loss of life.

With fluorescents, on the other hand, it’s a bit more complicated. For recent fluorescent technologies, it takes only about five seconds of use to use the same amount of power that it requires to start up, according to the U.S. Department of Energy (DOE). However, since frequent switching does decrease the life of fluorescents, experts recommend shutting them off only if you won’t be using them for 15 minutes or longer.