Over the past few years I have been more and more interested in getting some kind of electricity monitoring system. Ideally one that does electricity, water, temperature, humidity well lots of sensors. I like the idea of parametrics, telemetry of living if you will. In fact I do not share this fascination alone, my dad loves the idea of these things also.

More recently I bought and setup a ubiquitous Raspberry Pi (RPi) and that sits there acting as my home OwnCloud and NAS system. So it would be great to use it as part of the energy monitor setup. Logical as well.

So I was of course very happy when I discovered the OpenEnergyMonitor (OEM) people. This initial happiness quickly disappeared when I realised a lot of their systems required me to build them myself. Now my soldering skills are present but not anywhere on the lines of useful when dealing expensive parts.

I kept on looking at all the various energy systems both for myself and my dad and was really happy when I found out that OEM had decided to produce finished assembled products as well. But then it all went wrong again. Due to a lot of unexpected bills I had to rethink my purchasing timeline. But I went on the OEM website to cost up the price of the systems one for me and one for my dad. It was very, very, very expensive. In fact stupidly so. I also went and installed the OEM web system for the RPi and quickly realised that this was not the product for my dad. There was a £50 overhead just to get a Pi, the Radio parts and a SD card with pre-built image.

So I carried on looking and found quite a few products that were more appropriate for my dad:

I’ve now settled on a plan. I will move ahead with the OEM system for myself. This is perhaps a foolish mistake but I like supporting open projects and perhaps that is worth the excess in price compared to the more mainstream system. Ironically the mainstream system I am thinking of getting is called “LightwaveRF” and I went for this for my dad because it gave both energy monitoring and remote control capability which really appeals. The irony being that I could also buy that system for myself and save a world of pain that I can see coming. In fact at the time of writing this I am going backwards and forwards over getting the OEM or “another” system as I would like home automation. I wonder if the OEM system will also allow for this in the future? Possibly since the RPi has the wifi transmitter/receiver it could readily talk to other devices? However, reading their forum and chatting on twitter makes me doubtful. But then again reading many blogs imply the JeeLabs protocol being used by OEM could extend to many other devices.

By getting the two components from LightwaveRF I can save money and have a simpler system for my parents house. No need to think about RPi things for them, no need to program the EmonCMS, etc, etc.

Of course by using the RFM12Pi V2 radio system in the RPi am I then cutting off access to cool things like the Zigbee or Z-Wave. With that said there appears to be a lot of cool things out there that are compatible with the RFM12Pi unit. But even more for enocean! With that said the RFM12Pi and OEM would be compatible with emonTH but at the time of writing this they are £22 each. Do I need to know how cold it is in another room before I get there? My head says no my heart says of course you want one in each room including the bathroom.

For me my home is already wired with Clipsal C-Bus2 and I was thinking it would be really nice to link that with my RPi in some way. Of course that is much harder than it sounds and definitely more complicated than it should be. O’and did I forget going to be way more expensive as well. Sigh.

It is rather frustrating my home alarm system talks to a system that sends out alerts and phone calls (BMS) - that system could also interface with the lighting and water guard system but currently doesn’t. The WaterGuard system has a flow sensor/switch which would be really good to take a value off and feed to the OEM system so it could record water flow as well unless it is a switch then it probably wouldn’t work. However if I am lucky and my unit used the flow sensor rather than a reed switch I’d still need to buy/build a signal splitter and there is no guarantee that the signal would be compatible with the OEM emonTx V3 system.

So in short I have a WaterGuard leak protection system that is all alone doing it job but could: isolate in the event of an alarm, report leaks alerts via the BMS system. It also has a flow sensor/switch which could link to the OEM system if I knew how to wire it may be. And the BMS could also do more than just report if the alarm is going off. It could also interface with the lighting system as well. All of this could in an ideal world link to the RPi to allow monitoring and home automation. It won’t because it doesn’t and so I am left scratching my head and wondering wouldn’t it be better just to buy some nice LED replacements for my halogen lamps so I don’t have to sit in the dark all the time?