Energy consumption monitoring with Vera
Duncan SampleHaving purchased a Current Cost home energy monitor, finally I've gotten round to ordering the USB cable, so I can see how it works with Vera.
Vera
Vera is my home automation master controller, produced by Mi Casa Verde. It's basically an Asus wireless broadband router with a custom OpenWRT firmware installed, but it has the added benefit of 2 USB sockets, one of which is used to connect a Z-Wave controller stick.
Having the Z-Wave controller connected to the router means that, with their custom web UI (which I'm not too fond of) I can control the z-Wave capable devices around my home.
The marketing all points to Vera helping a household keeping their energy usage under control by remotely monitoring and controlling the devices in your home. For instance, you can set it to send you an SMS if it's a weekday, at a time you're supposed to be at work, and certain devices are on.
That's where the Vera falls down. It tries to keep track of how much energy each device uses, but the information needs to entered manually, so is time consuming, and not very accurate (do you know exactly how much energy all your devices use?). It also doesn't take into consideration devices which you aren't controlling Vera (Z-Wave plugs aren't cheap).
Current Cost
Enter Current Cost. A device costing £40, coming in two parts, a transmitter & clamp and a remote display. You place the clamp around the power cable going into your electricity meter and by the power of induction, it magically measures the electricity throughput. From reading a few forums they're not 100% accurate, but it's a lot more accurate than guesswork/Vera and would give an overview of the total consumption, not just certain devices (although now they also sell device monitors to use in conjunction with the same remote display).
The most interesting part (for me) of the Current Cost offering is the opportunity to buy a USB cable for it (although not standard USB) and connect the display to a computer to take a stream of information from it.
Although there's no official driver for Linux, Paul Mutton put together some nifty scripts for pulling the data stream (and Jamie Bennett added a correction for USB).
Since Vera is basically a Linux box, I should be able to make the Perl scripts Paul describes run in some way on Vera. The question would then be how to make use of that data in a sensible way (ie. how to integrate it into the Vera software). Ideally I'd like to be able to trigger things to happen based on time and the reading from the Current Cost unit, so I don't have to have Z-Wave modules for every device (though they'd be the only ones I could turn off automatically).
Comments