These are my views on wireless vs wired, open vs close, cloud vs local... based on community conversations I had, it is a bit long, but would love to hear your feedback.
Smart devices are strongly associated with wireless communication, and a wired Smart Home may seem like a contradictory concept. However, the truth is that wired connections have many practical advantages. Like with any technology decision, each alternative has strengths and limitations, and they key is combining them in ways that maximise benefits.
There is a wide range of wireless communication protocols, many of them competing on the same band like WiFi, Bluetooth and ZigBee on the 2.4GHz frequency. This may not sound like much as they are different protocols, but when a smart house starts to have many devices, the end result is all those devices are fighting for their piece of wireless spectrum, resulting in extra data packet collision and therefore more attempts to communicate.
Below is a visualisation where these wireless protocols operate on the 2.4GHz frequency.
In its own this is ok, however as the number of devices keeps increasing, not to mention neighbourhood devices too, added to the ever increasing use of IP for Audio and Visual entertainment… and before we know, we have wireless war zone inside our home.
There’s of course ways to improve on this, however I do strongly believe that patching should not replace good design. When it comes to a Smart Home & Building Automation, good design prevails, if you can wire… wire it, it will stand the pass of time.
Wired connections are fast and versatile - nothing beats the transmission speed and compatibility of a conductor carrying a voltage signal. When using wired connections, the signal is guaranteed to reach its target. When I talk about wires, I’m not only talking about IP wires only, I’m also thinking about energy, security systems, even some essential sensors like in rented accommodation where smoke alarms need to be wired.
A Wireless home
When I started the process of upgrading my own Smart Home a few years ago, I went all wireless, mostly a mix of ZigBee, Z-Wave and WiFi; these included a long list of:
• Window and door open / close sensors
• Motion sensors through out the house
• Alarm bell and battery monitor
• Energy metering – main house energy
• Fuel consumption for heating
• Smart Thermostatic valves [TRVs]
• Thermostats
• Temperature, Humidity, CO2 and air quality in general
• Window blinds
• … and probably a few more I cannot remember now. Last time I checked I had about 500 metrics at home.
After less than a year, I found myself losing some of the sensors connectivity, often due to low battery which I had to replace pretty much every year. But also I started to experience delays on information as my Smart Home gizmos grew, for example from the time of opening a door and getting a notification on my phone or having the event announced in one of the speakers, it could pass several seconds.
Then I had the issues with energy metering, I’m a big fan of energy monitoring, I work on it for a living and having jumps on my energy data meant I could not understand why things were happening. That added to having to reset wireless sensors so they would reconnect again was a massive pain and time waste.
I use energy data to fine tune the energy efficiency of my home, without out, I cannot track if the changes I’m making are a positive thing or not. One day I was explaining this to a friend and he asked me what would I do with all this “smart-stuff” if I ever was to sell the house?
Hhmmmm…. Good question!
A Wired home
That question haunted me for a while as I spent a lot of hours and money setting up the home to be smart(er), yet if I ever had to move on and sell the house… I would probably be able to recover nothing from all that investment, and taking them with me was probably a waste of my time too.
I decided that from that day, any modifications or additions I was to do to the house to make it smarter it would need to be a solution that could become part of the house. That would add value to the property and most importantly it would be able to run without continuous IT / tech support from me. – Yes, it was starting to become a nigh job just to keep all that tech working.
Converting a house into a wired smart home is not easy, and unless you are doing a major reformation I would recommend to take it in small steps. At least this is what I did, and still working on it.
My first step was to replace all those battery operated motion, door and window sensor for wired ones. Since I did that, I never have looked back! No more batteries to replace, no worries if the wireless signal is delayed, now everything runs really fast and most importantly, it runs ALWAYS.
With this in place, I accomplished my first step on adding value to the (smart) home, by making some changes that could stay within the home without any technical support. Even if the Smart Home controller was to be removed, the wires would still be there for any potential Alarm system or even a commercial controller.
All the house zones have their own wired motion sensor, doors and pressure pads have also their wired sensors too. I live in a busy house and the logs from those sensors are manic, probably the reason why they were eating batteries before I did the change! - The image below, every line means movement detected, the solid part of the chart is movement non-stop.
You probably are thinking, where all those sensors were wired to? Well, they were (and still some are) attached to a very ‘hacky’ version of machinon I made nearly 2 years ago. In fact, this is where all started for machinon.
My next step was getting a good handle on energy usage within the building. As I have quite a bit of experience on this through my work, it was quite an easy job, in a couple of weekends I wired throughout the house some CTs (current transformers), small energy meters, main electrical meter and even a flow meter for my heating fuel consumption.
Most of these are really pulse counters, I used a software based version for this with a Raspberry Pi, still works today, however the accuracy of hardware pulse interrupts of the Raspberry Pi (and probably any SoC) is not up to the job compared with a dedicated hardware for it, and that is what I did.
You probably can see now why machinon has so many I/Os and many of them are counters, it was my way to accurately alleviate a computer of continuous real world interrupts. Now, even if the computer was to crash, machinon would still keep counting and keeping them in memory.
Still much more to do, my next step is connecting some circuit heating valves to machinon and get rid of those battery eaters Smart TRVs. I have tried a few zoning systems and my experience has been a bit mixed, what I learnt is that if not careful, these new zoning wireless heating system will consume more if not dealt with the properly… and I know because I did measured the before and after. - Maybe another blog for this...
I don’t really trust opening and closing a water valve with a wireless device. In some of the projects I have been involved for work, you have the signal to trigger the event, say open a valve; and then you have a sensing signal to check that the valve has indeed been opened, and these are wired.
This may be a bit overkill for a home, in my opinion it does add value and confidence to the building that has been designed to stand the pass of time.
Never ever Wireless?
Of course not!, it brings many convenient uses. My main point in this blog, is that because it is convenient, it does not mean is ideal for all the use cases.
I use it, in fact I still use Z-Wave, 433MHz (aka the wild west of wireless) and EnOcean but I use no WiFi for my smart home devices, as I do not know what those devices are doing on my network or what data is been sent.
Unfortunately I still have to use WiFi for CCTV which I hope to change soon. They are blocked from Internet access, however still compete in bandwidth with some of my Audio and Video streaming system.
The Smart Home House property
Although wired connections may seem archaic in a smart platform, consider they are intended for use in buildings - long-term investments that are designed to stand for many decades or even centuries.
Wired connections can stay in place for decades without adjustments, regardless of how many tenants use a home or a commercial space.
The value of having those wires in place, means that you can migrate to any Smart Home system you want without having to replace all the sensors for compatible ones.
If something changes in your wireless network (ie broadband provider, security passwords..) you do not have to worry about the house coming to a halt. It will still work, even without Internet.
Very important, you can still use your home as normal, even without the “smart” things.
Wireless connections are also more demanding in terms of security, since they are more vulnerable to intruders as they do not need physical access to your home. In contrast a wired installation is fixed in place, has almost zero costs after the initial installation and cannot be compromised from outside the property.
Another small advantage of wired connections is a higher energy efficiency, since many wired sensors operate without a power source - passive. This may not sound like much, but on average 2-5W per mains powered device times several 10s, you do the math over a year.
Security & Privacy
There’s one area I haven’t touched, which is important to me, and I assume for many of you too. When I started to write the wish list of an ideal smart home after spending over a year with wireless hubs, I came with these:
Reliable and not require me to tinker with it every night to keep it going.
It had to be 100% Internet independent, having my home data going into the cloud was a massive No, I just don’t see the need for it.
It would need to allow me to expand as required without having to replace the “home hub” or parts of the system every few years.
Most importantly, I had to own it, meaning if I wanted to modify it, I did not have to ask permission to any company. There, no Red Tape!
I’m sure I had a few more… but those sum it up really. Here is what I came up with:
Reliable -> I would bring my industrial background into it
Privacy -> It had to run locally, completely independent of the cloud or even the local network within the house.
Expansion -> It had to be open to expand, to add more, to use new technologies
I had to own it -> This was easy, take any small computer and give it arms and legs to sense the world around it. That is pretty much what machinon does.
Using a Smart Home to enhance your building Energy management
A expandable platform can also integrate with electrical panels and sub circuits, since they provide a common connection point for all circuits in a building. A wired smart home platform can be equipped with power meters to track the electricity consumption of each panel and even monitor the consumption of individual circuits.
With this approach, you can get a better snapshot of your energy expenses, knowing exactly which circuits consume the most energy, when it happen and how that ties with the human behaviour within the house. Can things be optimised around our daily routines?
I you have your own power generation or electricity storage system, with an expandable Home Automation system, you can monitor the whole building energy flow and therefore maximise battery and grid usage, where it goes and how it is used. It is only time before DR (demand response) is part of the Utilities new tariffs.
Like an alarm, if our home is DR enabled, we will be able to access better energy tariffs.
Conclusion
Although a smart building system can be designed completely wireless, the benefits of wired devices should not be overlooked. Wired infrastructure can last for decades without compatibility issues, and it provides the most cost-effective way to connect older equipment with modern smart platforms and its value will be possible to be transferred to the property and future owners.
Wireless protocols such as WiFi, ZigBee and Z-wave provide the flexibility to experiment with smart appliances, and the owner can reconfigure the system as desired without physical modifications. However, if you need smart devices that operate for years without compatibility issues and maintenance, then wired connections are the best option.
Adding any smart platform to a building does not imply that all devices should become wireless or wired, but that long term thought should be given to find a balance between the mobility of wireless technology and the long-term reliability of wired connections.
Machinon is designed with my personal experience of what a good Smart Home platform should be. It has been designed from the ground to give the freedom of choice. Whether you like wired or wireless, local or cloud, close or open software… the option should be yours, no one else. With machinon I hope to give the Smart Home enthusiast community options not seen before on commercial products.