Use Energy-Efficient Outdoor Lighting

Quick Facts Affordability Cost Savings CO2 Reduction The affordability rating is an average of the different types of lighting you might use outdoors.		Outdoor lighting can account for a large percentage of overall residential lighting energy use. It significantly contributes to lighting pollution, which prevents many of us who live in urban centres from seeing the stars. By switching to energy-efficient lamps, like compact fluorescent floodlights, metal halide or high-pressure sodium lights, you can reduce the energy you use. For example, high-pressure sodium lamps use 70% less energy than a standard incandescent floodlight and last up to 10 times. By directing light to where it is needed and using lights that shield the lamp and direct the light down rather than out and away, you can reduce the light that is cast into the sky and wasted.   Affordability There are increasing numbers of options available for energy-efficient lighting systems and styles. Different lamp types vary in price, but by making the switch you can save on your energy bill. Note that some kinds of lamps, High Intensity Discharge (HID) in particular, can only be used with specific fixtures. In addition, automating your outdoor lighting with sensors and timers will make it easier to ensure you aren’t wasting energy by having lights on when you don’t need them.    Cost savings A 100-watt incandescent light, which operates 10 hours a day at 8.27 cents per kWh, would cost 8.3 cents a day or $2.57 a month. With a 23-watt CFL, operating for the same amount of time and providing equal illumination, it would cost 1.9 cents a day or 59 cents a month – saving you $1.98 per month or $23 per year. Health & comfort Outdoor lighting allows you to walk safely on the path or steps to your home, lets you see who’s at the door before opening it and acts as a deterrent to criminals. Good outdoor lighting also minimizes the amount of light that shines onto your neighbours property and into bedroom windows, reducing privacy and hindering sleep. Environmental considerations Conserving energy is the best way to minimize the need for new energy generation facilities. Consider using solar walkway lights or solar led motion sensor lights as ways to save even more energy on your outdoor lighting. Directing light down to where it is needed reduces the amount of light that spills upward into the sky and reduces sky glow, which prevents us from seeing the stars in many urban areas.

What you need to know

Compact Fluorescent Lights

• CFLs use up to 75% less electricity and last up to 10 times longer than standard incandescent bulbs. This means you’ll not only save money on energy, you will also avoid the inconvenience and cost of frequent bulb replacements.
• CFLs are quick starting, and are sold in a variety of shapes, sizes, light levels and colour temperatures. Make sure you choose the right bulb for your fixture.
• There are CFLs specifically designed for outdoor use. Some are made to be used in enclosed fixtures, such as porch lights. Only use outdoor CFLs outside.
• Although extreme heat and cold will diminish the amount of light a fluorescent light will produce, many are now designed to start in temperatures well below zero – check the packaging for details.

Fluorescent lamps

Traditional T12 fluorescent lamps using magnetic ballasts (devices that convert electric current into the proper voltage, amperage and waveform to operate fluorescent lamps) have trouble starting at sub-zero temperatures, but more energy-efficient T8 lamps using electronic ballasts will start in temperatures up to -18°C.

High Intensity Discharge (HID) lamps

These include the groups of lamps commonly known as mercury, metal halide and high-pressure sodium. Metal halide or high-pressure sodium lamps are excellent choices for outdoor lighting and can be used as flood or area lighting. They provide high light levels with less wattage than mercury vapour and much less wattage than incandescent lamps. HID lights are not affected by low temperatures. They can be wall or ground-mounted, but can only be used in an HID light fixture. They also require a ballast to control power to the lamp.

Light placement

• Consider lighting a path from the entry at the street all the way to the door. If there is shrubbery near the entryway, use lighting to eliminate shadows.
• A long or steep flight of stairs should have lights at the top and bottom for safety.
• Direct the light to where is needed. Use lights that shield the lamp and direct the light down to help you see better rather than out and away. It will reduce the light that is cast in the sky and save energy.
• Avoid glare. A luminaire that emits a concentrated beam of light offers better visibility than one that shines light in all directions. In certain cases, glare can compromise safety.
• Post lanterns are particularly useful at entrances to driveways and walks. Avoid clear glass designs and exposed high-wattage lamps, as their blinding effect can be almost as hazardous as no light at all. Minimum height should be 2.4 metres above the ground to provide the most light.
• Floodlights on your driveway should be installed at least 3.6 metres above the ground. This will keep the light out of drivers’ eyes, protecting their night vision.
• Walk lights are low-mounted fixtures that spread their light downward. They’re best used for steps, paths and driveways, and should be placed 2.4 to 3 metres apart.

FAQ

Why does outdoor lighting use a lot of energy?
The energy used by your outdoor lighting will depend on the wattage of the lights and hours of operation. Since outdoor security lights have typically been incandescent and higher in wattage than indoor lights, the cost to operate them can be significant, particularly if a large number of high-wattage lights are used.

You can save energy by using more efficient lamps, like CFLs or high-pressure sodium lights, or by limiting the hours of operation with timers, photocells or motion detectors.

How does poor outdoor lighting cause light pollution?
Poor and excessive lighting not only costs you more, but also causes light pollution.  Poor outdoor lighting can shine onto your neighbours' properties and into bedroom windows, reducing privacy, hindering sleep and giving the area an unattractive look.

Light that spills upward and into the sky in urban centres causes sky glow, which reduces outr ability to see stars. Glare comes from overly bright source of light compared to background lighting levels. It beams directly from a lamp into your eye. It serves no purpose and hampers the vision of pedestrians, cyclists and drivers.