Sense energy monitor review: Your patience will be rewarded with great insight into your home’s electricity use

Sense is a bright-orange box that sits in your electrical breaker box and gives in-depth insight into your home’s entire power usage. The whole system is quite clever and—thankfully—free of any monthly charges. But it learns very slowly, and that’s likely to frustrate you.

Sense ($299 at Amazon) works by electromagnetically listening to the power flowing along the two hot wires that run from your electric meter to your breakers. By measuring the current flow a million times each second, Sense can observe changes in load with precise detail and, based on a machine-learning database, attempt to identify the footprint of different devices from the noise they generate.

This means it can tell you exactly how much energy different appliances in your house use, and it does all of this without requiring sensors or smart plugs on each device. Or at least, that’s the simple theory that disguises a very complex process.

Updated October 25, 2020 to report that Sense has added new Flex sensors ($50) that can be added to an existing Sense energy monitor to track energy consumption in larger homes (including those with split-service 400-amp service). The new sensors can also track a home’s standby generator, alerting when the generator takes over in the event of power outage and monitoring the home’s energy consumption.

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The main Sense unit that you install at your main electrical panel.

Installation

Installation is pretty easy and you can do it yourself if you’re not scared of opening up your electrical panel to expose the primary power lines coming into your home from your utility. Power for the Sense unit can be directly tapped inside the breaker box—just be sure to cut the power before doing this. But for the record, Sense says ”the safest route is for a licensed electrician to do the install.”

The device senses electricity flow through a couple of sensors that encircle the two service cables incoming from your utility. Sense has a slightly higher-priced model ($349) for homes with solar systems. It comes with two extra sensors that measure the electricity flowing from your panels, so it can compare the amount of electricity your solar panels are producing compared to the amount of electricity your home is consuming. But it depends on your solar power inverter being connected to your breaker box, versus being connected directly to your utility meter.

Sense needs to be added to your Wi-Fi network, and Sense supplies an external Wi-Fi antenna should the signal be too weak inside the metal breaker box. Installing the external antenna is simple if your box is surface-mounted: Just run the wire though one of the box’s existing punch-outs. This will be slightly more complicated if the box is recessed into the wall, but the whole thing is generally well thought out.

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Sense’s sensors clamp onto the main power cables coming into your circuit breaker.

Sensing my electricity use

It’s quite exciting to first launch the Sense app and watch your home’s electricity consumption in real time. You’ll probably spend a lot of time in the app in the first few days watching the system react as you switch appliances on and off.