According to the U.S. Department of Energy (DOE), residential lighting accounts for 5% of your home’s energy usage. Traditionally people have used incandescent lighting, which is not energy efficient as newer energy-efficient lighting sources. These newer sources include halogen incandescent, compact fluorescent lamps (CFL), and light emitting diodes (LED). One way to save energy is to swap your old incandescent bulbs with these newer lighting options. According to the DOE, swapping out 5 of your most used incandescent bulbs can save you $75 on your energy bill per year.1
These bulbs work on the same principle as your old incandescent bulbs, but they have a capsule inside that holds gas around the filament to increase the efficiency. Another benefit for the bulbs is that they can be used with traditional dimmers. Halogen bulbs use approximately 75% of the energy when compared to traditional incandescent bulbs.2
Compact Fluorescent Lamp (CFL)
These bulbs are a curly version of the long tube fluorescent lights you may see in supermarkets and in office buildings. An ENERGY STAR qualified CFL uses about 25% of the energy compared to traditional incandescent bulbs and lasts 10 times longer while putting out the same amount of light.2 These bulbs do contain a small amount of mercury; thus they should always be recycled at the end of their lifespan. Check out the EPA’s website for more information on what to do when one breaks or where to recycle them in your area.
Light Emitting Diodes (LEDs)
Also known as solid-state lighting, are semiconductors that convert electricity into light. ENERGY STAR qualified LEDs use 20-25% of the energy compared to incandescent bulbs and will last about 25 times longer.2 The price of these bulbs is expected to decrease as they become more widely available in the market.
Other strategies that help decrease your lighting energy use include utilization of natural light, outdoor solar lights, and smart lighting control systems.
By utilizing the natural light coming into your home, you can avoid using lights all together during the daylight hours.
Outdoor solar lights
These lights use batteries charged by solar energy. The lights are easy to install and essentially maintenance free. Common uses include pathway lighting, wall-mounted lamps, freestanding lamp posts, and security lights.7
Smart Lighting Controls
can help you save energy by automatically turning off lights as needed. The DOE estimates that occupancy and sensors can cut lighting energy use by 30%. Three common types of controls include dimmers, motion sensors, and timers.5
New energy efficient bulbs typically have a higher initial cost than that of traditional incandescent bulbs. Even though incandescent bulbs are initially cheaper, that doesn't necessarily mean that they are cheaper in the long run. The CFLs and LED lights last 10-25 times longer than incandescent bulbs, and typically use 20-25% less energy than the incandescent bulbs. With these savings, both LEDs and CFLs will lead to long-term savings for your home.
Payback and cost savings varies based on the amount each light is used, the initial cost, the cost of electricity, and how many lights are replaced. For instance, if you replace five incandescent bulbs with five newer 9.0 W LED bulbs with an average usage of 3 hours per day, at the electricity price of Ohio ($0.11/kWh), and an additional cost of $9.60/light bulb, you can expect a payback for that investment of 1.3 years. If you have Microsoft Excel, you can use ENERGY STAR’s lighting saving tool to calculate your savings by providing these inputs.4
1"Lighting Choices to Save You Money" by Department of Energy
Introduction to newer lighting options.
2"How Energy-Efficient Light Bulbs Compare with Traditional Incandescents" by Department of Energy
An energy comparison for 43 W (halogen) incandescent, 15W CFL, and 12W LED compared to traditional 60W incandescent bulbs.
3 "The ENERGY STAR Choose A Light Guide" by ENERGY STAR
A great guide to learn about where each of these light types may be used.
If you have Microsoft Excel, you can use ENERGY STAR’s lighting saving tool to calculate your savings by providing the number of lights, type of light, average daily usage, energy costs, and the initial cost. If you don't have Microsoft Excel, there is a simplified tool version of the tool you can use.
5 "Lighting Controls" by Department of Energy
Introduction to lighting dimmer controls, motion sensor controls, occupancy sensors controls, photosensor controls, and timer controls.
6"5 Benefits to a LED Motion Sensor Light" by doityourself.com
7"Outdoor Solar Lighting" by Department of Energy
Short discussion of outdoor lighting.