Got a spare PC? How to open-source your smart home - for free

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ZDNET key takeaways

Home Assistant OS is an open-source controller.

Control as many smart devices as you need.

The OS is free and can be installed on a spare PC.

Smart homes make sense. The devices that bring a certain level of automation to your home are exciting, and they can also lower your energy bill and help make your abode a bit more secure.

But just how smart is your home? Do you have devices all over the place that you control with your phone or various hubs? Lights, cameras, action? Maybe you've considered purchasing one of the several smart hubs, such as the Amazon Echo Smart Hub, the Google Nest Hub, or the Apple Home App.

Also: How I cut my power bill with IFTTT automation - in 4 simple steps

What if I told you there was an operating system that could serve as a control center for all of those smart devices? Even better, what if the OS could auto-discover those smart devices on your network?

Well, that system is available and is called Home Assistant OS. It's not your typical operating system, as it's built around Docker and uses the container engine to run the Home Assistant Supervisor and manage the core and various add-ons. By using this method, Home Assistant runs very efficiently on single-board computers and off-the-shelf PCs (or even virtual machines).

You can even purchase pre-built machines, such as the Home Assistant Green, so you don't have to bother installing the OS. The Home Assistant Green sells for $219 on Amazon and is the simplest way to get started with Home Assistant.

But if you're a DIYer at heart, like me, Home Assistant OS is the way to go.

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Home Assistant OS is fairly easy to install, so long as you have some OS installation skills.

I'll walk you through how I got Home Assistant OS up and running via VirtualBox. First, let's talk about what it can do.

What is Home Assistant OS?

Home Assistant OS is a platform that enables consumers to run the full Home Assistant smart home platform on commodity hardware. This OS provides automations, dashboards, integrations, blueprints, updates, and backups.

With add-ons, you can include functionality for services and devices, such as Z-Wave, Thread, AccuWeather, Actron Air, AdGuard Home, Amazon, Android TV Remote, Anthropic, Apple, Philips Hue, and much more. There are hundreds of add-ons available that cover just about every type of smart home device and service you can imagine.

You can add areas, users, electricity grid connections, and target activities. You can also view history, media, and even create/manage to-do lists.

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And, if you have smart devices in your home, you can control them.

Installing Home Assistant OS

Installing Home Assistant OS isn't terribly challenging, as long as you have a bit of skill with operating systems (especially Linux).

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It's much easier to install Home Assistant OS on a spare machine than to run it as a virtual machine. The steps for installing on bare metal are:

Download the Home Assistant OS image file.

Decompress the .img file using the xz tool, as in: xz -- decompress file.xz.

Create a live USB drive using the BalenaEtcher tool.

Boot the live USB and follow the installation wizard.

Installing as a virtual machine requires a bit of trickery. After you download and decompress the .img file, you'll need to rename it to an .iso. As an example, if the file name is haos_generic-x86-64-18.0.img (after decompression), you would rename it like so:

mv haos_generic-x86-64-18.0.img haos_generic-x86-64-18.0.iso

Once you've completed that step, you can create a virtual machine using the ISO in the same way you would any normal VirtualBox virtual machine. Follow the simple (albeit text-based) installation, and you're ready to go.

Once the installation is complete, you'll see a text-based screen with the information you need to access the web-based interface. You should see an IPv4 address, which will be used in conjunction with port 8123:

http://192.168.1.220:8123

Make sure you use the IP address assigned to your Home Assistant OS instance.

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You will be presented with a "Create user" page, where you'll need to type a name, username, and password. Once you've done that step, click Create account.

Next, you'll need to find your home location using your zip code.

Home Assistant OS will then scan your network for compatible devices. Naturally, what the OS finds depends on the devices you have.

You'll finally land on the default dashboard, where you can start managing your smart home.

Adding devices

Before you add a device, you'll want to add an area. To do that, go to the Overview, click +, and then click Create Area. In the resulting pop-up, add the necessary information for the area, and click Create.

Click on the new Area, click +, and click "Add device." In the resulting pop-up, search for your device, click it, and add it. How you add a device will depend on the device in question.

Once you've added a device, you can then control it from the Home Assistant dashboard. You can add as many areas and devices as necessary. You can access Home Assistant OS from any PC or laptop on your LAN. There's even a Home Assistant mobile app for Android and iOS to control devices from your phone.

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And that's all there is to creating a free, powerful smart home controller.