Thirty percent of all outdoor lighting in the U.S. is wasted, not serving the purpose for which it was installed. That’s about $3.3 billion in energy cost and the release of 21 million tons of carbon dioxide per year. To offset all this carbon dioxide, we’d have to plant 875 million trees annually. This, according to statistics released by the U.S. Energy Information Administration (EIA) and the International Dark-Sky Association (IDA).
We—homeowners, gardeners, even apartment dwellers—can light our homes, our patios, and our gardens with more attention to protecting the environment. You may want professional help or to make this a Do-It-Yourself re-lighting project. A DIY job will cost approximately $20/fixture, 10¢/ft. of cable, and $200 for a transformer, then the trenching starts. An outdoor lighting specialist’s fees will start around $2,000.
Either way, let me offer some helpful information:
1: The main criteria for environmentally responsible lighting,
2: The types of lighting customarily used for residences, and
3: Tips to help you work with your electricians or succeed as a Do-It-Yourselfer.
A key resource is the International Dark-Sky Association. They have criteria for ecologically responsible lighting and provide an evaluation and Seal of Approval that is granted to manufacturers of outdoor lighting fixtures and materials. Look for or ask for the IDA Seal of Approval on equipment you purchase or have installed.
1. The criteria for environmentally responsible lighting include:
- auto time controls, where appropriate
- glare control and minimized light trespass (keep lighting from spreading beyond the intended focus)
- minimize brightness
- minimize Blue Light emissions—prevent light that interrupts circadian rhythms (animal and human)
- maximize shielding (lights directed, preferably down) to avoid “sky glow”
2. Based on the affects you want to achieve in your front yard, back yard, garden, patio, driveway, and walkways, you can choose from variety of light sources, including:
- Solar powered garden path lights and string lights that vary in price, brightness, ease of installation.
- Brick lights that can be recessed into walls, pathways, even steps. Caution: Be sure they’re installed with easy access for replacing bulbs and batteries, or repairing wiring.
- Battery operated accent lamps.
- Battery powered curtain lights; dramatic strings of lights hanging down, creating a wall or cascade of tiny lights.
- Glow-in-the-dark paint, an often-overlooked option, adds an extra measure of safety along paths and on steps.
- Reusable glow sticks—LED or rechargeable.
- Solar and electric outdoor chandeliers
- Firepit: a cozy option for short-term gatherings.
3. In addition, consider these tips when you’re planning and designing your eco-friendly exterior lighting.
- What is the purpose of the lighting: atmosphere, emphasis, security, safety?
- Five traditional locations for lighting:
- House façade, avoid direct lighting on the front door or windows. Use a softer, spreading light directed at an architectural feature or plants near the entry.
- Trees, if you are using ground lights up, aim for the trunk and leaves. If you only aim at the tree’s crown it will look disconnected from the earth. If you can, add a few lights high in the tree aiming down, mimicking the shadows of leaves in the moonlight.
- Garden walls should be lit close to the wall to emphasize texture.
- Flower beds and pathways are perfect for shielded ground lights.
- Paths can be lit with well lights—circular and buried in the path.
Here are four final cautions to help you accomplish a satisfying project:
- Motion sensors cut down overuse of lighting and add security.
- Low wattage, outdoor bulbs, 50 watts or less, usually work best.
- Avoid bright lights streaming into neighbors’ windows and gardens.
- Use downward not upward lighting whenever possible to avoid dark-sky pollution.