Home Assistant on Raspberry Pi Can Turn NFC Cards and Appliances Into Smart Home Triggers

According to Engadget, Home Assistant currently has more than 1,500 integrations. It can use location, power usage, NFC tags or a device changing state to trigger automations. Home Assistant OS officially supports the Raspberry Pi 4 and Pi 5, with at least 2GB of RAM and a 32GB microSD card, and Engadget says it is the recommended installation for most people who bring their own Pi. The software is free, with no subscription or feature paywall, although optional services such as Home Assistant Cloud cost extra.

The first project turns NFC cards into a physical music or movie collection. Engadget said streaming is convenient, but movie night can become 15 minutes of scrolling. Home Assistant can use an NFC tag as an automation trigger. Users can assign stickers or cards to albums, playlists, movies or other actions and scan them with the Home Assistant app on a phone. The automation can be set up through Home Assistant's visual editor, so it does not require YAML. With a dedicated NFC reader, a card can be placed on the reader and Home Assistant can respond instantly without anyone picking up a phone. The system can also tell different readers apart, so the same tag could trigger different actions depending on the room. Engadget cited one builder who created a custom 3D-printed movie player using an ESP32 and an NFC reader, with physical cartridges for different movies; inserting one can prompt Home Assistant to use Plex to start the corresponding movie. The report notes that this is the enthusiast version and that most of the fun can be had with a few NFC cards and a phone.

A second project uses phone charging as a bedtime trigger. The Home Assistant Companion app can tell Home Assistant if a phone is charging, so plugging a phone in at night can start a bedtime routine. Engadget said conditions such as the time and whether the user is home are key. With those conditions, Home Assistant can turn off lights, lower smart blinds, adjust the thermostat or shut down devices left on downstairs. Without them, charging a phone at 3 p.m. could be interpreted as everyone going to bed very early. Android provides charging information directly through Home Assistant sensors, and iPhone users can use an iOS Shortcuts automation to trigger the routine as soon as a charger is plugged in. Engadget said the project may not require buying anything if the phone and the devices to be controlled are already connected to Home Assistant.

The third project makes a dumb appliance announce when it is finished. Engadget said a washing machine does not need Wi-Fi, a touchscreen or an app to join a smart home. In some cases, a smart plug with power-monitoring capabilities is enough. Home Assistant can monitor an appliance's electricity consumption and use that measurement as an automation trigger. A washer usually draws more power during a cycle before dropping toward its idle level when it is done. When Home Assistant notices that lower reading stays in place long enough, it can notify a phone. Engadget said the same concept is used by Home Assistant community members with dishwashers, rice cookers, coffee makers and other devices with predictable power consumption. The report advises monitoring the specific device rather than copying someone else's wattage threshold, because appliances have their own idea of idle. Users also need an energy-monitoring smart plug rated for the appliance being plugged in. Engadget said this is not a good area to be adventurous with high-power gear, but for the right appliance it is an easy way to make old equipment feel smarter.

The fourth project is intended to make a shopping list appear when the user reaches the store. Engadget introduces the idea by noting that remembering to make a shopping list is one problem.

Editor's Summary

Engadget outlined four Home Assistant projects for Raspberry Pi users: NFC cards for media playback, phone charging as a bedtime trigger, power monitoring for appliance alerts and a location-based shopping list. The report says Home Assistant is free, supports Raspberry Pi 4 and 5, and has more than 1,500 integrations. It also notes that many of the automations can be built with existing devices or inexpensive accessories, while some advanced versions require extra hardware.