How to light up your backyard, conserve energy and save money
By Steve Parrott
In an era of rising energy prices, looking at your electric bill can be a frightening prospect. Many homeowners are searching for ways to cut costs, and are looking to their outdoor lighting as a possible candidate for cutbacks. While its true that extinguishing all outdoor illumination—from security lights to decorative fixtures—would save some money, it doesn’t make for a very happy homeowner. After all, who really wants to hunker down in a pitch-black backyard?
Luckily, there is an energy-efficient outdoor lighting option, one that satisfies homeowners’ needs for security and safety, beautifies your home and enables you to enjoy outdoor activities. This solution is professionally installed low-voltage landscape lighting.
These lights aren’t the same as the ones available at ‘big-box’ stores, which can be installed in a matter of minutes. This lighting is designed by a skilled professional, who selects rugged and durable lights that last years (not months) and creates an intelligent lighting design that satisfies your many goals, including energy conservation.
How efficient is low-voltage landscape lighting?
Compared to typical 120-volt outdoor lighting, switching to 12-volt lights saves as much as 90 per cent in energy costs. The savings are realized because of several factors:
- Light efficacy: This refers to the amount of light (lumens) produced by a unit of energy (watts). Standard 120-volt bulbs have a low efficacy (about 10 lumens/watt); miniature 12-volt incandescent bulbs are 50 per cent more efficient, while light-emitting diodes (LEDs) are about 400 per cent more efficient.
- Lamp selection: Low-voltage lighting allows the lighting designer to select among dozens of wattages, from three up to 50 watts, and several beam spreads, from very narrow to extra wide. Typical 120-volt lighting provides a much smaller selection, resulting in wasted energy. Low-voltage lighting is all about projecting low levels of illumination over a wide area. High-voltage lighting tends to project overly bright illumination in a few isolated areas.
- Better control: Standard 120-volt outdoor lighting is turned on and off manually—when it gets dark, you flip on a switch, then turn it off in the morning. Low-voltage lighting, on the other hand, gives you much more precise, often automated, control. You can set on and off times according to when the lights are needed most and, by doing so, minimize the amount of time the lights are in use to conserve energy.
Control options for low-voltage lighting
Outdoor lighting professionals are well versed in various system control options. The most common configuration is the use of a timer in combination with a photocell. There are many types of timers and photocells, as well as other more sophisticated control options described below.
All timers work by allowing an electric current to pass through them when they are in the ‘on’ mode. Timers range from very simple to quite complex.
- Manual: This is the simplest (and least expensive) type of timer. It is set by pressing small tabs on a ring that correspond to the time of day; each tab represents 15 minutes. For example, by pressing down the four tabs between 6 p.m. and 7 p.m., the lights will remain on for the full hour.
- Digital: Digital timers offer a far more sophisticated pattern of on-off cycles. For example, the timer could be set to turn on the lights from 6 p.m. to 12 a.m., Monday through Friday, extended by another two hours on the weekend. Programming these timers can be complicated, but if you can master the skill, you can greatly improve your lighting configuration. Consult with a professional for programming tips.
- Astronomical: Astronomical timers are also digitally controlled, but offer another level of sophistication. Since sunset times vary according to the season, timer settings may need to change accordingly. Astronomical timers automatically shift the ‘on-off’ cycle to match the shifting sunset time.
- Interval: Some transformers come equipped with interval timers. These work in combination with a photocell to automatically turn on the lights at sunset and allow them to remain on for a set period of time.All low-voltage transformers contain a timer receptacle located inside the transformer housing. This is where most professionals install the timer. It is possible, however, to install the timer inside the home, usually in a basement or garage. The indoor location is most often used when an astronomical timer is employed, since they tend to be very large. Some transformers have timers permanently mounted inside the unit. This can be problematic, since timers have a limited life and may need to be replaced every few years.