What are smart devices doing that makes them so smart? There’s actually a smart computer inside them, running at all hours so that the device is ready to be triggered by timers, remote controls, or even voice commands. You may wonder if smart devices and smart bulbs, like the Lumimans (from Amazon) use electricity when they’re turned off, since this may affect whether or not you want them in your home.
Smart bulbs use a small amount of electricity even when off. This power use is required to keep the “smart” components on and ready to receive commands. However, a smart LED bulb is still much more efficient than a traditional light bulb.
While it might seem like an obvious source of energy inefficiency, this phantom load is very small, and on average makes no significant difference in either energy consumed nor electrical charges. In fact, this trace amount of power is what smart bulbs, even good ones like TanTan (on Amazon), require in order to be so smart and at the ready–features that allow the lightbulb to be even more efficient over time using timers and dimming.
Do Smart Bulbs Use Much Electricity when the Light is Off?
Because smart bulbs are controlled by tiny embedded computers that have to be on all the time waiting for commands, they actually use electricity for a much longer duration than traditional incandescent bulbs, or even energy efficient LED “dumb” bulbs. But how much energy do they use in this state? The good news is it’s not very much at all.
Depending on the bulb, this “vampire” power usage is anywhere from 2 cents to 20 cents per month. Why such a large window? Well, different smart bulbs have different communication standards (Wi-Fi, Zigbee, Z-Wave, etc.), and for that reason they can operate differently, requiring different amounts of power. But all of them use an incredibly small amount.
As you’ll see further down, when we compare the cost of incandescent, CFL, and LED bulb power usages, adding a couple cents per month doesn’t meaningfully affect the comparison. Even at the higher end of 20 cents per month, per bulb, the bulb is still using overall less energy over time.
What Makes a Smart Bulb Smart?
Smart bulbs are light bulbs that, while connected to the electrical grid via the tried and true light socket – even ones that aren’t specifically designed for it (like we explain in our guide) – are also wirelessly connected to the internet. This usually, but not always (it depends on the brand) involves a hub or smart-home network like Zigbee, ZWave, or in some cases, smart bulbs will just interface directly with the Wi-Fi network.
This access to the worldwide web enables the LED bulb to activate, dim, deactivate, and also to change color through using a variety of cues. For example, one could use a smartphone to control the lighting in their home from anywhere in the world. Along with simple devices like smart plugs (also our guide), smart bulbs allow you to add some seriously cool features to your house.
Smart Bulbs can also be cued by other bits of information available on the internet, such as sunset and sunrise times, or the day of the week. Smart bulbs can be also be cued by geofencing; when a trackable device such as a smartphone or smartwatch crosses a GPS established threshold, like when you’re pulling up to you home.
Ultimately, Smart bulbs can be used to maximize the energy efficiency and lifespan of the bulbs. Adding in neat features like like remote dimming and voice control, it’s clear why smart bulbs are a smart idea and more than just a technological vanity.
Why Smart Bulbs Still Use Power When Turned Off
The behind-the-scenes power draw goes by many names: phantom load, ghost load, vampire draw, standby power, etc. In many household devices, like a refrigerator, a phantom load is needed to monitor the temperature or run other components in the background. Even something like a kitchen toaster might use a small trickle of electricity to keep the circuit board inside ready to receive commands from digital buttons on the front of the device. In television, the remote control receiving sensor needs to be always ready for that energizing infrared signal from the remote, just to mention another common example.
In order for Smart bulbs to behave in an intelligent fashion, they must remain ever vigilant for the cue to change state, from either your Wi-Fi router or wireless smarthome hub. This awareness costs some small amount of electricity in the form of a phantom load. The amount of power draw from this phantom load depends on the brand and model of the Smart bulb, but it’s far less than what’s used to actually produce light.
Smart Bulb Energy Costs Compared to Incandescent and Fluorescent
There are a lot of ways to light your space, and a lot of light bulbs available to the average consumer. The best light bulbs are those that deliver the highest quality light, last the longest amount of time, and use electricity in the most efficient way. For our purposes, we can break down our lighting options into three categories: incandescent, fluorescent (CFL), and LED.
LED Lights Explained
LED stands for light-emitting diode. LED’s have been around for a long time, being used for flashlights and traffic lights. Now finding their way into the consumer market, LED’s work by electrons moving in sa pecially designed semi-conductor. LEDs are the most energy and material-efficient of the three types of light technologies.
Smart bulbs are LED light bulbs with a small attached Wi-Fi transmitter/receiver and computer. They add an additional layer of efficiency to the already efficient design of LEDs by their internet-enhanced control features.
Fluorescent Lights Explained
Fluorescent bulbs work a bit like neon signs; the glass tube contains a small quantity of liquid mercury and an inert gas such as argon. When an electrical current is added, the mercury becomes gaseous, which reacts with the argon, causing it to emit photons of light energy. This light can’t be seen by humans, so a phosphorous coating on the inside of the bulb is added, and that’s what lights up and emits light.
These bulbs use less electricity than incandescents, and they usually don’t have “smart” features built in, relying on the end user to add the “smart”ness at the switch if they want it.
Incandescent Lights Explained
Old-fashioned incandescent light bulbs are the most familiar kind of light, having been around since their invention by Thomas Edison in 1879. These bulbs work by using a highly electrically resistant material, often tungsten, which heats up and glows when a current is applied. In a vacuum, the filament cannot react with oxygen and burn out, hence the sealed glass container.
Of the three categories, incandescent light bulbs are the cheapest to manufacture and cost the least amount of money for the consumer. LED bulbs are the most expensive to manufacture, in part because they are newer to the consumer market, and cost much more per bulb than the other categories. Compact fluorescent (CFL) bulbs fall towards the middle for both factors.
However, in terms of energy efficiency and longevity, the bulbs reverse their order. LED’s are high energy-efficient bulbs. When compared to incandescent bulbs, LEDs can generate an equivalent amount of light (measured in lumens) with about 13% of the energy. LED’s use around 50% to 80% of the energy of an equivalently bright CFL bulb, according to Viribright.
When to Use Smart Bulbs to Optimize Cost
Smart bulbs take the superior design and material efficiency of LED bulbs and then add an intelligence factor. Although the data shows that LEDs are more energy-efficient in the long run, they cannot account for the lighting behavior of the users. Most charts regarding light bulbs indicate an average or estimated measurement of a certain variable.
For Smart bulbs, it’s not the design of the light element, it’s the superiority of the light’s performance. A Smart bulb can ensure that all of the lights in a room are always off when there’s no one in it, for example. Or activate and deactivate in phases based on the ambient sunlight within a room. Or, when away from the space, being able to work the lights remotely.
One aspect of Smart bulbs I found interesting, was the potential for Smart bulbs to mimic the natural light provided by the rising and setting of the sun. Even though the light source itself is synthetic, introducing the gradual change of light intensity, particularly in the morning, might be a very pleasant way to wake up.
| Incandescent | CFL | LED | |
| Watts Used | 60W | 14W | 7W |
| Average Cost Per Bulb | $1 | $2 | $4 or less |
| Average Life Span | 1,200 Hours | 8,000 Hours | 25,000 Hours |
| Bulbs Needed for 25,000 Hours of Light | 21 | 3 | 1 |
| Total Purchase Price of Bulbs Over 20 Years | $21 | $6 | $4 |
| Cost of Electricity (25,000 Hours at $0.15 per kWh) | $169 | $52 | $30 |
| Total Estimated Cost Over 20 Years | $211 | $54 | $34 |
In many cases, having an intelligent lightbulb in the room won’t result in a change of lighting behavior, and so won’t translate into energy or money saved. Imagine a bathroom light switch – it’s likely to be on only when one person is in the room, and in general, that person is probably used to using a light switch.
It’s not clear yet what the potential energy savings of smart bulbs are, as they’re new to the market, and a lot depends on the scope and type of application they’re used in. But they have the potential to be a game-changer, particularly in the long run, and for larger installations. There’s no question that choosing the LED bulb over the traditional incandescent will save you money, though it’s a bit tricky to come up with exactly how much.
When to Not Use Smart Bulbs
Smart bulbs have a lot going for them, but they’re not perfect for every application. One issue that might come up is a conflict when they are put on a light socket that is connected to a dimmer switch. Since smart bulbs use so much less electricity, a dimmer switch that is expecting to be controlling an old-school incandescent bulb will struggle to apply the same behavior to an LED. Probably, older dimmer switches simply won’t work with new LED bulbs, causing them to turn off quickly (as soon as you try to dim them) or leading to flickering.
Most Smart bulbs make use of either the existing Wi-Fi in your space or require the purchase and installation of a proprietary hub. These go by different names, depending on the brand of Smart home system you choose to use. This means that if you’re going to go with a Smart Bulb system, the initial expense might be more involved than just buying a light bulb.