What Is a Smart Home? Overview and Sustainability

High-tech appliances and systems could reduce the carbon footprint of your home.

Olivia Young is a writer, fact checker, and green living expert passionate about tiny living, climate advocacy, and all things nature. She holds a degree in Journalism from Ohio University.

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A smart home includes high-tech heating and lighting systems and appliances that can be controlled remotely with a phone or a computer. The term "smart home" only recently entered the lexicon of folks both tech-savvy and eco-conscious. Smart home technologies may include Google's Nest, Amazon's Echo, Apple's HomeKit, Ring, and the Ecobee SmartThermostat, among others.

Smart home automation (SHA) is ripe with benefits: Apart from convenience, it can improve energy efficiency, maximize home security, and grant access to remote monitoring. It has also been criticized, mostly because the technology itself must be powered around the clock.

Discover more examples of smart home devices—their benefits, drawbacks, and sustainability—and how to make your smart home even more environmentally friendly.

Someday, there might be an all-encompassing SHA kit for purchase. For now, smart homes typically comprise a range of devices, gadgets, and systems that each have their own functions but can connect with other platforms for optimal functionality. Here are some common examples.

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Smart lighting can take the form of smart bulbs or smart switches—for maximum impact, a mix of both. Smart bulbs contain software that wirelessly transmits signals to and from a remote, be it a mobile app, switch, and/or smart home assistant. This way, the user can control lights from anywhere and program them to react to their environments—for example, to brighten or dim at certain times of the day or to activate motion sensors or voice commands.

Without a smart switch, such as an in-wall dimmer, smart bulbs operate with a traditional light switch that must be turned on for the bulbs to work. This gives smart switches a greater home energy-savings opportunity than smart bulbs alone.

Popular smart lighting options include Philips Hue's variegating Color Ambiance bulbs and light strip, Belkin's Wemo Smart Light Switch, wifi-connected LED bulbs from Govee and Wyze, among others, and Nanoleaf's illuminating hexagonal tiles.

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Smart thermostats connect a home's HVAC systems to wifi, allowing users to monitor and manage their heating and cooling from their smart home assistants or phones. Through apps, users can adjust the temperature of their homes and turn their HVAC systems on and off remotely. These systems are sometimes compatible with other devices, such as smart smoke alarms, to optimize safety, and can be programmed to maximize efficiency.

For example, you can set smart thermostats to turn down or turn off around the time you go to bed, or to turn on an hour before you get home from work. This saves energy and money, especially if you're able to evade peak hours when electricity is most expensive.

The Google Nest thermostat, for example, has a Rush Hour Rewards program that offers users monetary incentives to decrease their energy consumption during these peak times—easy to do with smart climate control systems. Smart thermostats besides Nest include models by Ecobee, Amazon, and Honeywell.

Home energy consumption accounts for 20% of all greenhouse gas emissions in the U.S. Even though the U.S.'s northernmost states, from North Dakota to Maine, consume the most energy nationally, Midwestern states emit the most greenhouse gases from electricity because their primary energy sources tend to be fossil fuels.

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After establishing smart lights and thermostats, the next phase of smart home automation is replacing inefficient appliances with high-tech alternatives. Almost every facet of a home can be made smart—washers and dryers, dishwashers, vacuums, ovens, and air conditioners, down to wifi-enabled pressure cookers and microwaves. With these snazzy gadgets, you can often schedule run times, receive phone alerts, and operate using voice commands.

The resource-saving features depend on the device. For instance, a smart sprinkler system can limit your household's water consumption by detecting the weather and skipping garden waterings on rainy days.

Without splashing out on all-new smart appliances, you can still monitor and manage the power your existing appliances are guzzling with smart plugs. Smart plugs like the ones made by Wemo, Ring, and Wyze allow users to turn off just about any device—as small as a lamp or fan or as large as a refrigerator or air conditioning unit—with a phone app or voice command (via a home assistant). These plugs can cut phantom loads, the electricity used by devices when they're off and in standby mode. They fit right into your regular power sockets and can often be programmed to turn appliances off and on at set times.

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Smart security systems à la Ring might include CCTV, door sensors, and alarm systems that help notify homeowners of invasions, fires, floods, and other disasters. These don't necessarily help with energy efficiency but are widely used for safety.

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Think of home assistants as the glue that holds your smart home together. The Google Nest ("hey, Google") and Amazon Echo (Alexa) are perhaps the most well known and most compatible with smart devices. HomeKit, aka Apple Home, is Apple's lesser-used platform. Home assistants have speakers and can serve as controllers, operating connected smart devices on voice command.

Smart homes are often lauded for helping to curb household energy consumption. How much they help is still unclear.

The U.S. Department of Energy's Energy Star program has estimated that smart lighting uses 90% less energy than traditional incandescent lightbulbs. Nest says its smart thermostats save the average household 10% to 12% on heating costs and 15% on cooling, but the Illinois-based power company ComEd found the daily average energy savings to be more like 1.5% in a study of smart thermostats across 3,200 households.

In 2017, the International Energy Agency (IEA) reported that smart home automation could result in a 10% reduction in energy consumption "by using real-time data to improve operational efficiency." Regardless of the data, reducing energy expenditure curbs our collective reliance on fossil fuels, and the ability to monitor energy usage comes with financial incentives. The U.S. Department of Energy says a smart thermostat alone can save 10% a year on heating and cooling.

The main criticism of smart home automation is that the devices meant to reduce energy consumption are constantly draining power while on standby. They're often referred to as "vampire" devices, electrical devices that continue to use electricity when they aren't in use. A 2015 life-cycle assessment study of smart devices concluded that their largest environmental impact was, indeed, their use-phase electricity consumption, but it also found the energy payback time to be negative by 1.6 years.

Energy payback time (EPBT) is the time it takes for an energy system to generate or "give back" the amount of energy used to produce and run the system.

Here are some ways consumers can help ensure their smart home systems are helping the planet, not hurting.

Apart from the biggest environmental drawback—that they run constantly, if only on standby—smart home systems get flack for being expensive and internet-dependent. It should be noted, however, that many devices can still perform limited functions without wifi.

HomeAdvisor estimated in 2022 that the average cost of a smart home was $785, although people could spend up to $150,000 to fully automate large, luxury homes. Keep in mind there are rebates and incentives available to offset the cost of energy-efficiency improvements.

Smart homes can save users up to 10% on energy bills, according to the IEA.

Start small with simple and inexpensive modifications like installing smart plugs and smart lighting. Later, you can consider upgrading to a smart thermostat and more high-tech appliances.

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"How Much Does a Smart Home Cost?" HomeAdvisor.