Phantom Load: How Much Standby Power Your Home Uses

By Cedrick Reese, ElectricityUsageCalculator.com

Phantom load, or standby power, is the electricity devices use when off or idle. Learn what it costs and how to measure yours.

Also called vampire power, it shows up in every home. The U.S. Department of Energy puts it at 5% to 10% of residential energy use, as much as $100 a year for the average household. One large California field study found it much higher, though its authors say the share is likely lower in other regions.

It's rarely the reason a single bill spikes. For that, see the main guide to why a bill spikes. But it's the part of the bill that runs every hour of every month, and it's the easiest part to measure yourself.

What counts as phantom load

There are two kinds, and the devices behind both are what people call electricity vampires:

Standby power is what a device draws while it's "off" but still plugged in: a TV waiting for the remote, a microwave clock, a charger with nothing attached.
Always-on idle load is broader. It includes devices that never really sleep, like routers, modems, cable and satellite boxes, DVRs, smart speakers, and game consoles left in instant-on mode, plus anything with a display, electronic controls, or a 24/7 internet connection.

In its audit of ten homes, NRDC counted an average of 65 electrical devices per home. Most of them draw only a little when idle. The problem is that they all do it at once, around the clock.

How much the research found

Estimates have grown as homes have filled up with connected devices:

1997: Lawrence Berkeley National Laboratory estimated the average home leaked about 50 watts, or roughly 450 kWh a year, about 5% of a home's electricity use.
2000: A Berkeley Lab study that measured ten California homes found standby power from 14 to 169 watts, an average of 67 watts, equal to 5% to 26% of each home's annual electricity use.
2015: NRDC analyzed smart meter data from about 70,000 northern California homes, plus detailed audits, and found always-on idle load averaged nearly 23% of household electricity. It estimated the national cost at as much as $19 billion a year, about $165 per U.S. household. NRDC cautions that the 23% share is likely lower outside northern California, where homes use more electricity for heating. Printers alone ranged from 2 to 26 watts of idle use per home.

The spread makes sense. The older studies counted narrow standby power. NRDC counted everything drawing power while not in active use. The DOE's 5% to 10% figure sits between them. For your house it depends on what you own, which is why measuring beats guessing.

Measure your own baseline

You can find your whole-home always-on load in one night, with no equipment beyond the meter you already have.

Use smart meter data if you have it. Log into your utility account and find the hourly usage view. The lowest hours, usually around 2 to 5 a.m., are your baseline. A reading of 0.15 kWh in an hour means about 150 watts running constantly.
Or read the meter twice. Use the overnight meter check from our main bill guide; the meter reading calculator helps with the math.
Subtract what's supposed to run. A refrigerator, freezer, furnace fan, or heat that cycles overnight isn't phantom load. If those are running, take the reading on a mild night or note when they're off.
Find the big ones device by device. A plug-in energy monitor or a smart plug with metering shows the exact standby watts of anything you plug into it. We compare options in best energy monitors and smart plugs.

What a baseline costs per year

A constant load runs 8,760 hours a year. Multiply watts by 8,760, divide by 1,000 for kWh, then multiply by your rate. Here's what that looks like at 18.23 cents per kWh, EIA's forecast U.S. average residential price for this winter. Annual averages are lower (about 16.5 cents in 2024), so treat these as the high end:

Annual kWh and cost of a constant always-on load at 18.23 cents per kWh
Always-on load	kWh per year	Cost per year
25 W	219	$39.92
50 W	438	$79.85
100 W	876	$159.69
200 W	1,752	$319.39
164 W (NRDC's northern California average)	1,437	$261.90

NRDC itself rounds its 164 W average to about 1,300 kWh a year. Every 10 watts you remove for good saves about 88 kWh, or roughly $16 a year at that rate. One forgotten DVR can matter more than a drawer full of phone chargers. To price a single device at your own rate, use the kWh cost calculator.

What's worth unplugging, and what isn't

Unplugging everything isn't realistic, and it isn't necessary. Go after the devices with the highest idle draw first, which your monitor will reveal in minutes.

Usually worth a look

Game consoles in instant-on or rest mode. NRDC measured one console's instant-on mode adding about 12 watts to its always-on load (as of 2015), so turning instant-on off is worth doing if you don't need it. See game console usage.
Cable and satellite boxes and DVRs. Many keep working in the background when "off," so their idle draw can sit close to their on draw (NRDC found set-top boxes drawing 16 to 57 watts around the clock in the homes it audited). Ask your provider whether a smaller box or a streaming app could replace one.
Desktop computers left in sleep, and printers. Shut down the desktop overnight and put the printer on a switched strip. Our desktop computer guide covers sleep versus off.
Old audio gear, subwoofers, and anything with a glowing display that you rarely use.
Seasonal and spare devices, like the guest room TV or the garage stereo.

Usually leave alone

Your router and modem. Unplugging them breaks smart devices, security cameras, and phone service for many homes. Their draw is modest; see router usage.
Refrigerators, freezers, and anything with a safety or medical role. Those loads are doing a job.
Phone chargers with nothing attached. Chargers generally draw little with nothing connected; a plug-in monitor will show you yours. Unplug them if you like, but don't expect it to show up on the bill.

Tools that make it automatic

A switched strip or a timer works better than remembering to unplug things every night.

Power strips with a switch. The Department of Energy points out that when you flip off a strip, the devices on it are truly off. Group a TV, console, and sound bar on one strip and switch it at bedtime.
Timers and smart plugs. Schedule the printer, coffee setup, or office gear to cut power overnight and on weekends.
Device settings. Turn off "quick start" and "instant on" features you don't need, and set screens and computers to sleep sooner.

Then check your baseline again a month later. If you're also fighting a high winter bill, remember that this load is steady all year, while heating is what changes. The winter electric bill guide covers that side.

The standby and idle load figures on this page come from three organizations: the Department of Energy's Energy Saver guidance, two Lawrence Berkeley National Laboratory studies (1997 and 2000), and NRDC's 2015 Home Idle Load study, each cited with its year because the methods and the homes measured differ. The yearly cost table is straightforward multiplication at EIA's October 2026 winter price forecast. Cedrick Reese wrote this page and plans to update it if DOE, a national lab, or NRDC publishes newer whole-home measurements. Prices last checked October 2026.

Sources

Standby figures vary widely by device model and age. The research numbers here are averages from the homes each study measured, so measure your own devices before deciding what to change.