As I was switching my house heating to a dual-fuel system (replacing an old AC with a heat-pump and keeping my existing natural gas furnace), I figured it would be a good idea to add an energy monitor to see how much power I was actually using. After shopping around a bit and confirming a friend had this installed along with his solar panels, I decided to go for the Emporia Vue 2 with 16 monitors.
While I am not an electrician, I am also not too afraid of working in my electrical panel. So unless you are confident in doing so safely, you may want to have an electrician install the unit. Basically, you need to attach some probes around electrical wires and then plug those probes into the unit (note which circuits correspond to each port you plug in to). It’s quite easy to do and there’s not much risk if you turn off the main breaker so no power is flowing through (and do it at night if you have solar panels as a 2nd source of energy). The only part that is more dangerous is putting the probes around the main as those wires will still be energised even if the breaker is off. Just make sure nothing is touching the un-insulated wires, put the probes somewhere that’s far from that area to minimise risk.
With 16 probes, I had a lot of choices as to what I wanted to monitor but decided to aim for the things I figured consumed the most energy:
- Heat Pump
- Kitchen refrigerator
- Basement circuit (1 chest freezer, 1 refrigerator, 1 computer +)
- Basement Panel Plug (Server, wifi router, printer etc.)
I didn’t use all the probes but mostly what was left was generic circuits that don’t have much load on them (incl. 4 kitchen circuits). I don’t have an electric vehicle or electric hot water tank so I figured this should mostly cover it.
I installed the probes, noting the correct direction and routing the wires around so they aren’t in the way. Double checked to see that the probe wires are secured in the monitor’s port (they tended to come out a bit when moving the unit to secure it). Since the main line comes in from the bottom of my panel, to secure the unit, I used two-sided tape so it would stay in the top section where there was room and a bit of wire management to clean things up.
After registering for an account and doing the initial set-up with the App, associating names to each port & adding 2x multipliers for the 240V devices (ie. Dryer, Stove, Heat Pump) got some readings!
Emporia Vue 2 Interface
The interface on the web or on the app is essentially the same so no advantage to using a computer to view it. You can display the information in text or graph form by second, minute, hour, day, week, month or year. I had a bit of fun looking at the graph/second map and seeing the impact when i turned some lights on or off.
You can also scroll back to see previous reading both in the graph and in the itemized view. It’s nice to compare the energy usage for all items on different days.
Using the Graph
The Graph view is useful to see what devices are using electricity and on which circuit. You can isolate the reading from one circuit to see how much power is being drawn and then turn devices on/off or unplug them to see just how much power they actually consume.
It’s interesting to see how some devices modulate their power (ie induction stove will ramp up and down frequently when an element is not at max power).
I will update this when I can but so far here are general thoughts:
It’s quite useful to see power usage, some small surprises in terms of what I thought was taking a lot of power, and what is actually taking a lot. It’s always nice to see data contradicting what you assumed :D.
Isolating devices and seeing the graph changes is kind of cool, useful to track down leaky/inefficient appliances or see behaviours you didn’t expect from some devices.
There is sometimes a bit of “generation” that is being read by the device when some powerful 240V appliances are on. Likely the balance between the two 120V legs isin’t exact (neither is the readings from the probes) and since we are just reading one leg going to the 240V device and multiplying by 2, it reads as though the device consumes more, and that the total consumption from all probes (with multipliers) is higher than what is being fed from the main so the Emporia Vue 2 labels the “remaining circuits” as generating power. It’s not much, but not something I expected. I assume changing the multipliers to something a bit below 2 would fix it, it’s not a huge deal at all.