Here is the second post on the series Smart Home Project 101. Today it is all about choosing the perfect smart home controller for the needs of the project. By the end of the post, you should have an idea of the different considerations and also what is my personal choice for my own project.
Why Do You Need a Smart Home Controller?
Let’s clear this out first…
Every company selling consumer electronics has decided to come up with its own line of smart home devices. In a way this is fantastic, more competition translates into lower prices (for the most part).
Of course, every company wants you to buy everything from them, however, the reality is that you will end up buying devices from different manufacturers. Different manufacturers use different standards. The result is that your devices don’t know how to talk to each other so it is impossible for you to have a seamless experience in your smart home.
That is why smart home controllers are so important. They are like the interpreters at the UN. I have never been to a Summit but I picture a bunch of people with different cultural backgrounds speaking in completely different languages…Interpreters understand those differences in culture and language and facilitate communication between nations (or devices in our case).
Requirements for my Smart Home Controller
Before choosing a home automation controller for your smart home project it is good to line up the requirements of your system.
These are mine…
- Flexibility: Home automation is one of my hobbies. I enjoy implementing different rules and automations (sometimes useless). For this reason, I want a very flexible and powerful system even if I have to lose in terms of simplicity.
- Budget Friendly: I want to keep the project budget friendly and favor DIY solutions when it makes sense.
- Scalability: Smart Home technologies change on a daily basis, I want to be able to extend the hardware or add new wireless protocols if I want to.
- Vendor Agnostic: I will get devices from different companies but I want the brain of my smart home to remain vendor agnostic.
- Established Platform: Smart Home platforms come and go, I am looking for something already established.
Smart Home Controllers: Types
This is my personal classification when it comes to choosing a system, by no means, this constitutes an industry standard…
When I refer to professional systems I am talking about companies like Control4 or Creston. These companies provide a professionally installed system so you don’t have to do anything. That includes everything from the smart home controller to sensors, actuators and lighting control.
They will tend to use more retrofitting and more sophisticated standards like KNX. It is a set and forget type of service and when something breaks you generally depend on a technician to get it fixed up.
Off-The-Shelf Smart Home Hub
They are very cost effective becuase you buy software and hardware with some of the main radios integrated (Z-Wave, Wifi, ZigBee, Bluetooth) altogether. The Smart Home hubs are designed with the average consumer in mind and hence they tend to provide a more polished user experience abstracting you from the complexity and nuances of a home automation system.
Open Source Home Automation Platforms
The third category comprises open source platforms that are independent of the hardware. On this group, we have home automation software like openHAB, Home Assistant, Domoticz, Calaos…You get my point.
Instead of being backed up by a company they are generally supported by a community of users and although there might be pre-packaged solutions, these alternatives tend to be independent of the hardware. The pace of development and quality of the releases depends entirely on the community of users.
Smart Home Wireless Protocols
Good old wifi is present on every home and that might be the reason becuase a lot of companies are leaning towards releasing primarily wifi enabled devices. The barrier to entry into the home automation world is almost nonexistent. We all have wifi at home.
There isn’t much of a choice here becuase pretty much any smart home controller will be able to support devices directly connected to the internet. This is pretty much a default option.
Bluetooth is another wireless protocol that has a high penetration on the smart home market. It has been there for the longest time and many of the devices we use on a daily basis have Bluetooth capabilities.
Bluetooth has also evolved a lot over time, adding some features that make it very attractive for battery sensors. I am referring to Bluetooth low power and more recently Bluetooth Mesh.
Z-Wave vs ZigBee
These two standards compete for the same position in the smart home space. They have three features that make them very suitable for home automation projects, especially for devices that should run on batteries for a long time.
- Low Power Radio: They use low-power radio to communicate with each other which is ideal for battery applications.
- Security: ZigBee and Z-Wave both use encrypted communication with AES-128.
- Topology: Both standards are mesh networks which means that every node connected to a power supply can act as a repeater, effectively extending the range of the network.
Some characteristics, however, set them apart.
- Range: Z-Wave has more range when it comes to communicating between nodes. In ZigBee, we are talking about 10 to 20 meters (30 to 60 ft) while the latest series of Z-Wave (700) can reach up to 100 meters (300 ft).
- Number of devices: ZigBee supports networks of up to ~65K devices while Z-Wave can only handle up to 252 devices. As I said before, they are both mesh networks which means that the messages hop from node to node until they reach the destination. Z-Wave is limited to only four hops while ZigBee has no limit on that.
- Compatibility: The Z-Wave standard is very strict when it comes to certifying new products while the ZigBee standard is somewhat opened… This means that you will find fewer compatibility issues between Z-Wave devices.
- Data Rate: ZibBee is faster than Z-Wave, 40-250 kbps versus Z-Wave’s 9.6-100kbps. Both of them should be sufficient for most of the Smart Home Applications.
Here is a great article explaining the differences in case you are interested.
Conclusions: Choosing the Best Home Automation Controller
It is time to make a choice…
Let’s start with the type of Home Automation Controller.
Professionally installed systems are out of the question. They are most definitely not budget friendly and since Home Automation is primarily a hobby for me, having a company doing all the work just takes away all the fun.
This leaves me with the off-the-shelf smart hub vs the open source home automation platform.
I will start by saying the smart home hubs are a great solution for users that are not planning to implement very complex behaviors and would like to have something functional from day one. Several of my readers are using Homey and they are very happy with it, I haven’t tried it myself.
For my personal project, however, I think an off-the-shelf smart hub will fall short. I can see some limiting factors:
- Generally, improving the existing hardware and adding new radios is not an easy option.
- For the most part, you depend on the company to release new features and support new devices. If it is not in the interest of the company to support certain devices or simply the company goes under…you are screwed.
- The product is designed for the average user, this means less flexibility in exchange for a nicer and easier UI. Not my thing…
After weighing the pros and cons, here is what I want to do. If you have been following the blog for some time, it is not going to surprise you 🙂
I am going to stick to my good friend openHAB. It is hardware independent and it has all the flexibility I need (and more). I have invested a lot of time in learning the platform and I think that is going to help to add value to my project and yours.
I don’t discard in the future doing a parallel run with Home Assistant to see how they behave with the same setup but for now, openHAB it is.
For the hardware component, I am not going crazy either, a Raspberry Pi 3 will do it. It comes with Wifi and Bluetooth and I can add more radios if I need to. If the project ends up outgrowing the Raspberry Pi, which I doubt, I can always scale up.
I have several Raspberry Pi’s playing different roles at home already.
For the moment, I am not planning to invest in extra radios, meaning ZigBee or Z-Wave. I am planning to build my own sensors using other wireless technologies.
I also think that Bluetooth, especially with the new mesh feature, will gain strength in the smart home space. Let’s see what happens.
If you don’t like tinkering with the hardware side and rather go with one of the major wireless standards, I would go for Z-Wave. I think you will end up facing fewer compatibility issues down the road.
By the way, if you are looking for a z-wave controller, the Aeotec Z-Stick is very well supported by openHAB and Raspberry Pi.
It is time to kick off the project…
This is the first step towards your Smart Home, it is time to install openHAB.
Let me know if you have any questions or suggestions about the project!