Smart Panel vs Smart Breakers vs Energy Monitor: What Each One Can Do for the Money

Smart Panel vs Smart Breakers vs Energy Monitor: What Each One Can Do for the Money

By EnergyBS Editorial Team | November 13, 2026

An Emporia Vue 3 energy monitor lists at $99.99 to $199.99 and can only watch. A SPAN smart panel lists at $2,550 to $4,100 before installation and can watch and switch circuits off, and SPAN says it is a certified energy management system (its spec pages list UL 916 and UL 3141) that can hold a service under a setpoint. Smart breakers and EV load controllers sit between those two, and each one does only part of the job.

So the useful comparison is not "which is best" but "which capabilities does my goal need, and what is the cheapest hardware that has all of them". A household that wants to find out why the bill jumped needs measurement only. A household adding a 48-amp EV charger to a 100-amp service needs a device that limits current and that an inspector will count. A household with a battery needs something that sheds loads when the grid is down. Those are three different products, and a smart panel is the only one that does all three, at roughly 13 to 41 times the list price of a monitor ($2,550 / $199.99 = 12.8; $4,100 / $99.99 = 41.0).

Four kinds of hardware that get sold under one word

"Smart panel" gets used loosely for anything that puts data from the breaker box on a phone. The four categories below behave very differently once you look at the spec sheets.

Clamp-on energy monitors. Current transformers (CTs) clip around the main feeders and, optionally, around individual branch circuit wires inside the existing panel. Emporia's Vue 3 ships with two 200-amp mains sensors and up to sixteen 50-amp branch sensors, samples 24,000 times per second, and claims plus or minus 2% accuracy on its product page. Nothing in the panel changes: the breakers, the bus and the service stay as they were. A monitor measures and reports. It has no relay and cannot turn a circuit off.

Smart breakers. These replace ordinary breakers one at a time in a compatible load center. Each breaker still trips on overload and faults, and it adds metering and a remotely operated switch. Leviton's 2nd Gen smart breakers are the clearest retail example: its LB115-GST is a 15-amp, single-pole GFCI breaker with remote on and off control, and Leviton's page says it requires the LWHEM Whole Home Energy Monitor to operate and is designed for Leviton load centers. Eaton describes AbleEdge smart breakers that integrate with a range of Eaton loadcenters and meter breakers, sold through its contractor network, with no price on the page.

Load controllers and EV energy management. These manage one or two big loads rather than the whole panel. The common residential version is an EV charger that reads the house's total current and slows or pauses charging when the house nears its limit. Emporia lists PowerSmart load management on its Pro EV Charger as "Level 2 charging with no panel upgrade". SPAN sells its own charger, SPAN Drive, at $750 plus installation, but only as an accessory to a SPAN panel.

Full smart panels. The panel itself is replaced (or, for SPAN's MLO model, added) with one that meters and switches every circuit from built-in hardware. SPAN's MAIN 32 lists at $3,500 with 32 controllable circuit spaces, a 225-amp busbar, and UL 67, UL 916, UL 869A and UL 3141 listings on its spec page. Schneider's Schneider Home platform describes whole-home and circuit-level management of solar, storage, EV charging and heating, without published prices on its connected-home page. Lumin takes a different route by controlling selected circuits beside an existing panel; our Span vs Lumin vs Leviton vs Schneider comparison covers that product and its installed prices.

The Department of Energy's Electric Panel 101 handout, produced with the New Buildings Institute, groups the last three together when it lists ways to cut a home's peak demand: "Smart panels or smart circuit breakers that control individual circuits to regulate a home's peak electricity demand", alongside power-efficient appliances and circuit-sharing devices. It does not list monitors there, and that omission is the first thing to understand about them.

The capability-by-price matrix

The table puts manufacturer list prices, read on November 13, 2026, beside what each category can and cannot do. Installation is excluded because it varies by region and job; the rows say who usually does the install.

Two rows decide most purchases. "What it can switch off" separates watching from managing, and "counts toward service capacity" separates managing for comfort from managing in a way an inspector accepts. A device can switch things off and still not count, if it is not listed and configured as an energy management system.

Per circuit, the list prices tell a clearer story

Box prices hide how much control each dollar buys. Dividing list price by the number of circuits each product meters or controls, using only the manufacturer figures above, gives this:

The working: $149.99 / 8 = $18.75; $199.99 / 16 = $12.50 (rounded from $12.499); $2,550 / 24 = $106.25; $3,500 / 32 = $109.375; $4,100 / 40 = $102.50. A SPAN circuit costs between 5.5 and 8.8 times what an Emporia circuit costs, and the difference buys a relay and a listing, not better measurement. If the reason for buying is "I want to see what the dryer and the heat pump use", that premium buys nothing you will use.

Leviton could not be put in this table because none of the Leviton pages read for this article showed a price for the LWHEM-2 hub or the 2nd Gen breakers. Installer quotes for Leviton and SPAN installed costs are collected in our smart panel comparison; we have not repeated them here because they come from installers rather than manufacturer list pages.

There is a second reading of the per-circuit numbers. A house rarely needs to control 32 circuits. The circuits worth switching in a capacity or outage plan are usually five to eight: EV charger, water heater, dryer, range, heat pump or backup heat strips, maybe a pool pump. Paying $109 a circuit for 32 circuits to control six of them works out to about $583 per circuit that matters ($3,500 / 6 = $583.33). That is the figure to hold against a targeted controller that manages only the one or two loads that cause the problem.

Where the capacity question actually gets decided

"Do I need a smart panel" is usually a disguised version of "can I avoid a service upgrade". The answer lives in the electrical code, not in the product brochure.

The 2023 National Electrical Code, adopted by many US states and municipalities on their own schedules, added a path for this. Eaton's summary of the 2023 changes puts it this way: "Load calculations are permitted to take advantage of an energy management system" when sizing feeders, service conductors and equipment, as long as the EMS is "in accordance with 750.30", and "the setpoint value for maximum amperes current is permitted to be used for the load calculations." The same page notes that the setpoint value "must be considered to be a continuous load." Mike Holt's 2023 calculations text describes the same section, 220.70, as letting "the ampere setpoint of the energy management system" be used for the maximum continuous load on feeder and service conductors, and points to 750.30(C)(1)(1).

Three conditions come with that permission:

1. It has to limit current. The point of 220.70 is that a device caps the current on the feeder or service at a setpoint. A monitor that only reports cannot do that, which is why it gets a "No" in the capacity row.
2. It has to be listed. Eaton's summary quotes 750.6: an EMS must be "Listed as a complete energy management system," a kit for field installation, or listed individual components assembled as a system. SPAN's spec pages list UL 916 (energy management equipment) and UL 3141 (power control systems). A homemade automation that turns off a smart plug when an app sees high usage is not a listed EMS.
3. It cannot override safety-related power. Per Eaton's summary of 750.20, an EMS may not override controls that keep alternate power available to fire pumps, healthcare facilities, emergency and legally required standby systems and critical operations power systems. That rarely touches a house, but it shows the code treats load control as safety equipment.

Mike Holt's example is the residential case most people are in: a 48-amp EV charger added to a 200-amp service. Where the charger at full nameplate would push the calculation past the service, a listed EMS controlling the charger lets the calculation rest on the setpoint instead of the charger's full nameplate, and the service may stay as it is.

The same arithmetic on a smaller service

Here is a labelled illustration, not a design. Take a house on a 100-amp service whose calculated load is 84 amps after a heat pump is added, and an owner who wants SPAN Drive, which runs at up to 48 amps (11.52 kW) on SPAN's spec page.

• Adding the charger at its nameplate: 84 + 48 = 132 amps, which is 32 amps over a 100-amp service before any continuous-load factor the electrician applies.
• With an EMS limiting the service, the electrician designs to a setpoint at or under what the service and the continuous-load rule allow, and the EMS slows the charger whenever the rest of the house is busy. On a winter evening with the heat pump and range running, the charger may get very little; overnight, when the house is quiet, it gets most of its 48 amps.
• The hardware for that, using SPAN list prices: $3,500 (MAIN 32) + $750 (Drive) = $4,250 before installation, taxes and shipping.

The question that settles the purchase is whether a cheaper listed controller limited to the charger would do the same job, because the charger is the only load in this example that pushes past the service. Where it would, the whole-panel route spends most of its money on the 26 or so circuits that never needed to be controlled. Our 100-amp load-shedding guide works through that choice in detail, including lower-power appliances and circuit sharing, and the panel capacity guide covers how the load calculation itself is done.

Canada follows a different code

The NEC sections above are US rules. Canada uses the Canadian Electrical Code, adopted and amended province by province, and the US 220.70 permission does not carry over automatically. The conditions for load management, the listings and what an inspector will sign are set by each province's electrical safety authority. Before buying any of these products to avoid a service upgrade in Canada, ask the inspection authority, or an electrician who pulls permits there, what device and setpoint they will accept on your service. A product page that says "no panel upgrade" is a marketing claim in either country until the permit says the same.

Blackouts: who decides which circuits stay on

None of the four categories makes electricity. In an outage the battery, generator or vehicle supplies a fixed amount of power, and the only thing a smart device adds is a decision about where that power goes.

Monitors go quiet. Emporia's product page says the Vue 3 "does not support local data storage" and needs an internet connection for real-time monitoring. When the grid goes down and the router goes with it, the monitor stops reporting. Even with the router on a battery, the monitor cannot switch a single breaker, so the house draws whatever the occupants turn on.

Smart breakers can shed if they are tied to the transfer switch. Leviton's LWHEM-2 page says the hub can integrate with an automatic transfer switch to shed nonessential breakers when backup power is active, and the load-center page describes non-essential loads shedding automatically when grid power fails. Two details matter. Remote on and off control needs 2nd Gen breakers; Leviton says standard and 1st Gen breakers stay on unless physically turned off. And the shedding only covers circuits that have a 2nd Gen breaker, so a panel with three smart breakers can shed three circuits and no more.

EV load management keeps doing its one job. A charger that limits itself against the house total will usually keep limiting itself on backup power, but it does not touch any other load. For a household whose outage plan is a portable generator and an extension cord to the fridge, this category adds nothing to blackout behaviour.

A full smart panel with a battery is the only category that manages the whole house off-grid. SPAN's panel page says that with a home battery the owner chooses which rooms and appliances receive power during an outage, and the MAIN 32 spec page says PowerUp "operates automatically in the background when on-grid and off-grid." SPAN also claims a 40% longer battery life in outages; its page does not explain how that figure was measured, so treat it as the maker's claim rather than a tested number.

What blackout control is worth depends almost entirely on the battery. A 10 kWh battery feeding a whole house will run down in hours if the electric dryer and the backup heat strips are allowed on; the same battery feeding only the fridge, a few lights, the furnace fan and the internet can last much longer. That runtime arithmetic, with real appliance draws, is in our critical-load battery sizing guide. Without a battery or generator, a smart panel's outage features have nothing to manage.

Time-of-use shifting does not need the panel to do the switching

On a time-of-use rate, the saving comes from moving flexible loads (EV charging, water heating, laundry, pre-cooling) out of the peak window. All four categories can help, but in different ways, and the cheapest one is often already built into the appliance.

Here is an illustration with stated inputs, not a quote for any utility: an EV that takes 10 kWh a night, on a rate with a hypothetical peak price of 30 cents per kWh and an off-peak price of 12 cents per kWh. Moving that charging from peak to off-peak saves 10 x (0.30 - 0.12) = $1.80 per day, or $657 a year if it happened every day of the year (1.80 x 365 = 657). Swap in your own utility's prices to get your figure; our time-of-use strategy guide explains how to read the rate schedule. We priced the same question on real rate schedules, with payback years, in smart panel time-of-use savings: worked bills.

Now ask what each device contributes to that $657:

• The EV charger or the car's own scheduler captures nearly all of it, for no extra hardware. Most Level 2 chargers and many vehicles can start charging at a set time.
• An energy monitor contributes by showing whether the schedule is working and what the rest of the house does in the peak window. Emporia's page lists "Smart Scheduling" of connected Emporia devices, Peak Demand Management and Excess Solar Management, but those act on Emporia plugs, chargers and batteries, not on panel circuits.
• Smart breakers can put a schedule on a hard-wired load with no timer of its own, such as an older resistance water heater. Leviton says 2nd Gen breakers support scheduling.
• A smart panel can do the same for every circuit, and adds a cost view: SPAN's page says the app shows energy use in dollars based on the utility rate plan you enter.

A whole smart panel bought only for time-of-use savings has to beat the free scheduler in the car or charger, and in most houses it cannot, because the big shiftable loads already have their own timers. The panel earns its place in the TOU case only when several hard-wired loads lack schedules, or when a battery is involved and the panel coordinates charging and discharging against the rate.

The decision rule, by goal

Pick the row that matches the main reason for buying. If two rows apply, take the more capable answer only if the cheaper one cannot cover both.

Three tests catch most wrong purchases before they happen.

The switching test. Write down every action you expect the device to take on its own. If the list is empty, buy a monitor. If the list has one load on it and that load is the EV, start with the charger. If it has four or more circuits, the per-circuit arithmetic above starts to favour a smart panel.

The permit test. If avoiding a service upgrade is the reason, ask the electrician to name the setpoint and the listing on the quote before anything is ordered. "The app will turn things off if it gets busy" is not a design an inspector signs. A quote that cannot name a setpoint has not solved the capacity problem.

The panel-brand test. Smart breakers only make sense when the panel already accepts them. Leviton's 2nd Gen breakers are designed for Leviton load centers and need the LWHEM hub. A house with another brand's panel that wants smart breakers is buying a new panel either way, which changes the comparison: the choice becomes a new smart-breaker panel or a new smart panel, not "a few breakers versus a whole panel".

Two households, two right answers

These are illustrations built from the list prices above, not quotes.

A household on a 200-amp service with a high winter bill. Nothing new is being added. They want to know whether the old electric water heater, the baseboard heaters in the basement or the dehumidifier is driving the bill. The answer is a $149.99 Vue 3 with eight branch sensors on the largest circuits. Even if the monitor shows the water heater runs during the peak, the fix is a timer or a heat pump water heater, not a $3,500 panel. Our home energy monitoring guide covers how to read what the monitor shows, and smart plugs handle the plug-in loads the panel sensors cannot separate.

A household on a 100-amp service adding an EV, a heat pump and an induction range, with a battery on the way. Three new big loads have to share a small service, and the battery needs someone to decide what it powers in a storm. This is the case smart panels are built for: listed load control on several circuits, metering on all of them, and outage priorities. The SPAN hardware alone runs $3,500 to $4,250 depending on whether SPAN Drive is included, before installation. The alternative to price against it is the service upgrade itself, and our panel upgrade cost guide shows what that costs.

Between those two sits the household that needs only an EV charger on a tight service. For them a whole smart panel controls 26 or more circuits they will never touch, and the targeted controller is the honest first quote to get.

What the spec sheets leave out

A few gaps came up when reading the manufacturer pages, and they are worth asking about directly.

• Leviton prices. Neither the LWHEM-2 page nor the LB115-GST page showed a list price on November 13, 2026. Get a written price for the hub plus each breaker you plan to use, then compare that total with a monitor or a smart panel.
• What happens when the internet drops. SPAN's spec pages read for this article do not say how the panel behaves with no internet. Emporia states plainly that the Vue 3 has no local storage. Ask any seller for the offline behaviour in writing, since a load-control device that depends on a cloud server is a poor fit for a code-required setpoint.
• Square D and Eaton retail options. Schneider's connected-home page describes Schneider Home's circuit-level management but did not list a Square D smart breaker. Eaton describes AbleEdge smart breakers sold through contractors, and its energy management circuit breaker story describes a field test with EPRI and 12 utilities beginning in fall 2016 rather than a homeowner product. In practice that means asking an Eaton-network contractor what is available for your panel.
• Sense hardware. Sense's homes pages now describe the Sense Home app delivered through Wi-Fi smart meters installed by participating utilities, with no subscription fees from Sense or the utility, and they did not list a price for in-panel hardware. If your utility is not a Sense partner, check the meter eligibility page before planning around it.

For the deeper technical side of smart panels (relays versus thermal breakers, cybersecurity and local control), see our smart panel deep dive. All panel topics on the site are gathered on the electrical panels hub.

Frequently Asked Questions

Do I need a smart panel to monitor my energy use?

No. A clamp-on monitor installed in the existing panel measures whole-home use and individual circuits. Emporia's Vue 3 lists at $99.99 for mains only and $199.99 with 16 branch sensors. A smart panel adds switching and, for some models, a listing that counts toward service capacity, which monitoring alone does not need.

Can an energy monitor help me avoid a service upgrade?

Not by itself. The 2023 NEC lets a load calculation use an energy management system's setpoint only when the system limits current and complies with 750.30, including listing. A monitor reports current but cannot limit it. It can, however, show real demand data that helps an electrician judge how close the house is to its limit.

Are smart breakers cheaper than a smart panel?

For a few circuits, probably, but Leviton's product pages did not show prices when we read them on November 13, 2026, so we cannot give a list-price comparison. Leviton's 2nd Gen breakers also need the LWHEM hub and a Leviton load center, so a house with another brand's panel faces a panel change either way.

Will a smart panel keep my house running in a power outage?

Only with a battery or generator. The panel decides which circuits get the backup supply; it does not create power. SPAN says owners with a battery can choose which rooms and appliances stay powered, and that PowerUp works off-grid.

Is there a subscription for these devices?

None of the manufacturer pages read for this article charged one. Emporia describes a free app with unlimited cloud storage, SPAN says its Home App is included with every panel and software updates are free, and Sense says neither Sense nor the utility charges subscription fees for the Sense Home app.

Does the US code rule apply in Canada?

No. NEC 220.70 is a US rule. Canada uses the Canadian Electrical Code with provincial amendments, and the provincial inspection authority decides what load management it accepts on a given service. Ask it before buying a device to avoid an upgrade.

Sources

Manufacturer list prices and specifications are from the Emporia, SPAN, Leviton, Eaton, Schneider Electric and Sense pages listed in the citations, read November 13, 2026. Prices exclude installation, taxes and shipping and can change without notice. Code text is quoted from Eaton's 2023 NEC energy management summary and Mike Holt's 2023 NEC calculations excerpt; your local adopted code edition and amendments govern.