More Building Matters
A home’s electricity use is affected by many factors. The efficiency of the home, the type of equipment in the home, and the habits of the occupants all play a role. Until recently, monitoring electricity use required complicated equipment. That’s all changing.
New innovations allow for monitoring whole electrical panels or individual circuits through technology integrated directly into the panels or breakers. Other technologies that have been around for a while include aftermarket products that can be installed inside panels. There are also options that allow point-of-use metering or utility-usage monitoring performed directly though the utility meter. These electrical-monitoring options can be installed in both new and existing construction. Electricity usage is billed through an electrical meter that is usually located somewhere outside the home. These meters monitor watts consumed by the home and are billed in 1000-watt units, or 1 kilowatt. The current average electricity rate in the United States is around $0.14 per kilowatt hour (kWh). To figure out cost, multiply the kilowatt-hour usage by the rate.
These meters record usage for the entire electrical load of the home. Gaining a deeper understanding of specific electricity use will require some way to monitor individual electrical circuits or appliances.
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7 Comments
Even in a new install, I'd choose the Emporia Vue over a smart panel. Just get a big enough panel that the clutter is manageable. It's a cheaper solution, and it's more modular--you aren't locked into a system that might become obsolete.
That's a great point.
I am not a techie and I have installed a couple of Emporia Vue with relative ease. At under $200, they provide a surprising amount of good data. Also, there is no need to monitor every circuit. Better to just focus on the circuits that are seeing significant power usage; it's cheaper, it reduces the clutter in the panel and on the data sheet.
Why does the Emporia Vue have to be installed in the panel box? So many are crowded! In cases where the non metallic (romex) cable or even metallic cable is accessable why can't it be clamped on that cable? For instance, my mini splits each have their own 15 amp 240 circuit, with BX/AC cable running in an exposed spot. Can I clamp one of these onto that cable?
The current transformer (CT) clamp needs to be around the individual current carrying conductor, they do not work if clamped around the cable also containing the neutral and ground conductors. You are absolutely correct, very difficult (and sometimes might result in an electrical code violation) when the panels are very full.
Thanks. Is that also true for 240 volt circuits?
Hi Nick,
You will need two separate CT clamps, one on each of the phase conductors (current carrying), usually black and red.
Randy
I'm a big fan of the Emporia Vue units and have successfully (and easily) installed a set in a guest house. I am unable to do so in our main house, though, since the main service panel gets its power via a bus bar and not wires. I'm also not a huge fan of the fact that the Vue is cloud-dependent but at least it's possible to easily "hack" it to run entirely locally since it's ESP32 based. I would rather that not be necessary.
The Square D panel is very interesting save that it uses a re-badged Sense as the circuit monitoring unit. That's unacceptable to me since I think Sense embodies the worst of the machine learning. When it works, it's magic but when it doesn't (as it frequently doesn't), then it's a big shrug of the shoulders because there's nothing you can do about it.
The Span panel is close to ideal. It is also cloud-based which would be a fatal restriction for something this important, but they do have an unofficial local API and there is at least reason to think that it COULD be made an official API.
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