Smart Plugs and Phantom Load: What You Can Actually Save
Standby draw is real but modest — typically a small single-digit percentage of a household bill. Smart plugs pay off on a handful of genuinely idle, higher-draw devices, not on phone chargers.
Standby load is the easiest energy-saving story to tell and one of the easiest to overstate. It's genuinely worth addressing — just not first, and not everywhere.
What standby load actually is
Devices that appear off often aren't: they're waiting for a remote, keeping a clock, holding a network connection, or charging an internal battery. Individually the draw is small. Across thirty devices running every hour of the year, it adds up to a modest but consistent share of the bill.
Where a smart plug earns its place
- An entertainment cluster — television, console, soundbar, streaming box — idle overnight and during the working day.
- A desktop workstation with monitors, dock, printer, and speakers.
- Garage or workshop equipment used a few times a month.
- Seasonal loads that otherwise sit powered year-round.
Where it doesn't work
| Device | Why not |
|---|---|
| Phone and laptop chargers | Modern chargers draw very little when idle; the plug may use as much |
| Router and modem | Cutting power drops the network and recovery is slow |
| DVR / set-top boxes | Scheduled recordings and guide updates fail |
| Refrigerators and freezers | Never — this is not a standby load |
| Anything with a clock you rely on | You'll reset it repeatedly and stop bothering |
Putting a number on it
Use the same arithmetic as any other appliance: watts ÷ 1,000 × hours × your rate. A cluster drawing 20W continuously is 175 kWh a year — meaningful at a high rate, marginal at a low one. That's the honest scale of this opportunity.
What to do next
Borrow or buy a plug-in meter and check five suspects: the TV area, the computer setup, the garage, the kitchen counter appliances, and anything with a permanent standby light. Put smart plugs only where the measurement justifies it, and spend the rest of your attention on heating, cooling, and hot water.
Sources
- Energy Saver: Save Energy, Save Money — U.S. Department of Energy. Consulted July 22, 2026.
- Residential Energy Consumption Survey (RECS) — U.S. Energy Information Administration. Consulted July 22, 2026.
- Energy Star product guidance — U.S. EPA / DOE — Energy Star. Consulted July 22, 2026.
Frequently asked questions
How much does phantom load cost per year?
It varies by household, but it's typically a small single-digit percentage of the electricity bill — real money over a year, but far less than heating, cooling, or water heating.
Which devices are worth putting on a smart plug?
Ones that are genuinely idle for long stretches and draw more than a trickle: entertainment centres, desktop setups with monitors and peripherals, garage or basement equipment, and seasonal items.
Do smart plugs use electricity themselves?
Yes, a small amount continuously to stay connected to Wi-Fi. On a device with very low standby draw, the plug can cancel out most of the benefit.