I’m planning to build a house in the future and one of the things i really want to make happen is a clear and nice home automation.
I know that there are various ways to do this and so far I am pretty happy with openhab2. The main reason not to go with openhab is the server based concept in my opinion but so far i did not have any severe problems regarding stability. I think on rock solid hardware like a linux system or even a mac mini that would offer great media server capabilities as well it would be running smoothly. Or would you go for a Bus system like KNX? I see the benefits (direct communication, wired setup, standardized protocol) but I am a little overwhelmed by the costs and planning effort I have to do in advance. I still got time to get into this, don’t get me wrong but before that I wanted to hear your opinion. Maybe you built a house yourself or have some thoughts you’d like to share with me.
at first, try to see openHAB as a bridging tool between various insular systems. You can’t have THE solution for everything within one system. That being said, you need to decide, which technology fits your needs in whatever aspect.
oh! As you mentioned stability and stuff. Try to use as much “proprietary” technolgy as possible. I would never trust any home automation with the complex task of controlling my heating. Not that I consider openHAB unstable, even if it was 100% stable, I do change items and rules, and therefore I could (and have! ) crash my OH-Installation. If this happens, when I’m away in winter holiday - I come back to a frozen home. So I use a failsafe heating system, which my Installateur setup. I only address some scenes or change target temperatures and stuff… Keep that in mind!
As we don’t know your requirements, so for a start a few thoughts:
KNX is a good start for most of home automation, as it is an open Standard, there are plenty of sensors, actuators and stuff. I would go for KNX for every new built or renovated house. KNX is reliable, stable and scalable as hell!
if you’re using hardware, which don’t has KNX-connection or only with much expensive add-ons, you can add them mostly via some kind of connection (TIPP: I would recommend using hardware with open API standards or easy access)
If I would build a new house, I would go through everything from cellar to roof and try to think of how I can make use of automation and/or getting Information.
As a beginning here some food for thought:
electric power, water and gas consumption (powermeter readout)
everything regarding heating, ventilation, …
security (door, windows, …)
Mailbox and or private parcel Station
temperature and room temperature Controlling
garden (watering, mowing, lighting, …)
all kinds of electric in my house (lighting, outlet, TV, …)
you see, there’s so many possibilities and openHAB gives you the freedom to connect devices, actions and information. But as always in live: you have to make some base, meaning the hardware for wires, built-in sensors (e.g. if you like to have the floor temperature, you can’t add this one later). But you’re free to add whatever you like (unless it doesn’t have a accessible API or something).
So my last advice is this: If you decide for a hardware, make sure you have open access to it and not just in a (public) cloud - first of all, you have to access the cloud (perhaps with additional monthly costs) and secondly, what happens when the vendors shuts the cloud down? You have the hardware, but can’t access it anymore. That’s why, I’m longing to replace my cloud-based door bell - no Integration possible (the promised API was quietly shut down after I bought it) and I can only use it in an App and not within openHAB…
I hope, this brings you a step further? if not - just ask!
One thing I will reemphasize is that one of the advantages of home automation is that sensor data from disparate sources and technologies can be used to drive the automation. Unless you stick with a single technology and that technology supports device-to-device communication, you necessarily require a central “controller”. There is no other way to bridge the technologies.
For example, you will need a central controller (or at least it will be an order of magnitude easier to implement, maintain, and modify) to implement the logic that, for example, turns on the KNX light when the Zwave motion sensor in the garage triggers, but only if the network sensor indicates someone is home based on their phone being on the network.
Now, there are lots of things you can do architecturally to mitigate this dependence on a central controller. For example, If your lighting is controlled both by OH and by physical switches and your HVAC is controlled by a traditional thermostat that lets one set the target temp through an API of some sort, then if the controller goes down, your smart home may become a dumb home, but it won’t become unusable. So make sure important controls have a physical equivalent and your guests will be happier and the impact of a down controller becomes much less pronounced.
from my experience putting OpenHAB as a main brain of your home automation system could be a disaster and not because OpenHAB is not reliable but because if you have central point which controls everything that’s single point of failure.
I use a bit different approach. I create devices with logic and decision making inside them and I use OpenHAB for monitoring every device state and setting configuration to devices using MQTT. In my opinion that’s the better approach. In this case even without OpenHAB, device will work with default values or with latest set through MQTT values for some time.
For example: if I want to create a device which turns on heating when temperature reaches 22 degrees and turns it off at 24 I would attach to the device the sensor and the actuator and I would make these tresholds as variables which have default values in the device configuration/program and receive updates from OpenHAB. This way you have very dynamic infrastructure which is also able to survive hardware/OS/Openhab upgrade failures without interfering severely your automation experience and personal comfort.