Automatic Savings: The Impact of Motion-Activated Lights

By Ygrene on September 8, 2017

Dimmers, motion-activated switches, and light timers can all help lower your energy usage. In many cases, homeowners who pair their lighting control upgrades with high-efficiency bulbs or fixtures enjoy even greater savings. It’s important to understand, however, that these lighting control tools are not one-size-fits-all solutions. In the right context, they can indeed lower energy costs – but in other situations they might not be beneficial, and they may not work at all if paired with the wrong fixtures or bulbs.

Here is what you should know before you decide to upgrade your home’s lighting controls.

What Controls Are Available?

Various types of lighting offer different advantages and disadvantages. The key to getting the most out of this particular home improvement project is to find the right combination of lights, switches, and sensors for your home’s needs. Dimmer switches and light timers have been around for decades, but new technology has improved their performance in terms of energy efficiency and reliability.

The other “family” of illumination controls utilizes sensors to decide when to turn lights on or off, including heat, motion, and sound sensors that will turn on lights when someone enters a room and turn them off after the occupant leaves. Light sensors will also turn off bulbs when there is sufficient natural light to illuminate an indoor or outdoor space.

What To Know About Dimmers

Homeowners have used dimmers for decades to control the brightness of their lights. These days, dimmers may help save on lighting costs as well, under the right circumstances. Their biggest advantages are that the switches are relatively cheap and new models do not get hot like their predecessors did. Dimmers will work with incandescent bulbs, but they decrease the bulb’s output, not its wattage: the bulb eats up energy as it gets dimmer.

If your goal is energy savings, you would probably save more money by getting low wattage bulbs instead of dimming higher wattage bulbs. Alternatively, you could pair dimmer switches with high efficiency bulbs. Some dimmers may work with LED or compact florescent bulbs, but only if the bulbs are specifically designed for dimmers. Likewise, the dimmers must be compatible with LED and CFL technology to produce the desired result. Luckily, most bulb and switch manufacturers clearly label dimmable functionality, so you should be able to gauge a product's compatibility simply by looking at the box.

Getting The Most Out Of Light Timers

Timers turn lights on and off at the same time every day. This can save money on power costs over time, because it will protect against leaving lights on accidentally. Homeowners can also use timers to turn lights on and off when they’re not home, thereby saving energy. Timers can be especially effective for outdoor lighting, such as porch lights. The timer will turn on the lights during evening hours and then turn them off when they are no longer needed, also helping to minimize energy costs.

Because timers measure the length of time that lights are on, these products can help homeowners become more aware of their usage and inspire them to incrementally to reduce consumption. Timers are compatible with all types of light bulbs and fixtures, so homeowners can easily use these products with their existing lights.

Sensors Explained

Light switches with various types of sensors can provide energy savings, but they can also be inefficient in certain situations and applications. The obvious advantage of outdoor motion-detector lights, for example, is that they will only turn on when someone or something is nearby. Overall, then, they will use less energy than standard lights or lights that are controlled by timers. However, this is only true if they are paired with a timer or a photo sensor (light sensor) – the light will actually waste energy if it’s turned on during the daytime when it senses motion. Photosensitive lights can also be used by themselves outdoors without motion detectors. These lights illuminate at dusk and stay on until dawn automatically. They are especially convenient in northern latitudes where sunset can vary by several hours depending on the time of year, making a timer switch inconvenient.

Indoors, infrared or sound sensors can detect when someone enters a room. These controls are often grouped together and called “occupancy sensors.” They turn the lights off when they no longer sense anyone in the room, protecting against energy loss from leaving lights on when no one is using them. Occupancy sensors work best in rooms that are not constantly occupied: bathrooms, guest rooms, walk-in closets, basement rec rooms, and so on. In these low-traffic areas, if someone leaves the light on, you may not notice for several hours (even days). A sensor would protect against this energy waste. However, in living rooms, kitchens, or main bedrooms, a sensor might be more of an inconvenience than a money saver – especially in larger rooms where a sensor might not detect that someone is still there and turn off lights that remain in use.

Pairing Appropriately

Sensors can protect against absentmindedness, in terms of turning lights off in low-traffic rooms or outdoor areas. Timers can help homeowners plan out and potentially cut their monthly energy costs, and dimmers may also provide some modest energy saving benefits when paired with the appropriate lighting. In fact, these improvements will all work best if combined with energy-efficient light bulbs and lighting fixtures.

How To Pay For Your Lighting Upgrades

Cost can be a barrier between homeowners and a complete lighting control upgrade that would give them real energy saving benefits. Luckily, PACE (property assessed clean energy) financing can help pay for such upgrades. Improvements that lead to greater energy efficiency may qualify for PACE programs. These programs help property owners cover the upfront costs associated with efficiency improvements. Homeowners are then able to pay for the project over time through an addition to their annual property taxes.  Over time the potential savings produced  by the improvement may lower the overall costs to the property owner.


PACE can help you finance hundreds of energy saving projects. Find out if PACE is available in your area – contact Ygrene at (855) 901-3999; info@ygreneworks.com.