Updated October 6, 2026. First published March 15, 2024 and refreshed with current information.
A typical office desktop is in use about eight hours a workday. For the rest of the week, nights and weekends included, it often sits idle with the monitor lit, doing nothing useful. Multiply that by every desk and it shows up on the power bill.
We worked out what that idle time costs, per PC and for a 20-PC office, in four places with very different electricity prices: Anchorage, Reno, Atlanta and Phoenix. The good news is that fixing it is mostly a matter of settings, not new equipment. This is about desktop workstations only. Servers, network equipment and phone systems stay on.
How much power an idle desktop uses
ENERGY STAR, the U.S. government energy-efficiency program, publishes test results for every computer and monitor it certifies. We looked at its current lists as of October 2026:
- Desktop PC, on but idle: the median certified desktop draws about 10.5 watts. A quarter of them draw about 19 watts or more.
- Desktop PC, asleep: about 1.6 watts (median). Switched off: about 0.4 watts.
- Monitor (23 to 27 inch), on: about 14 watts (median). Asleep or off: well under 1 watt.
So a desktop and monitor left on and idle draw about 25 watts together, and about 2 watts asleep. We use the 23-watt difference below. That is conservative: certified models are among the more efficient on the market, and machines with graphics cards or larger screens often draw more.
ENERGY STAR gives its own example (published February 2024): an office with 400 employees, each with a computer and an extra monitor, could add over $9,400 a year to its electricity bill by turning power management off, “with no added value.”
The program is moving from the EPA to the Department of Energy under a plan finalized in 2026; the power-management advice does not depend on which agency runs it.
The math, one desk at a time
Our assumptions:
- A month has about 730 hours. The PC is in use 8 hours a day on about 22 workdays, or 176 hours.
- The other 554 hours or so, it is either left on and idle, or asleep (or shut down).
- Left on and idle, a desktop and monitor draw about 25 watts; asleep, about 2 watts. Savings: 23 watts.
Energy saved per PC each month is watts saved times hours, divided by 1,000: 23 × 554 ÷ 1,000 ≈ 12.7 kilowatt-hours (kWh). That is about 153 kWh a year. Shutting down instead of sleeping saves slightly more. Multiply by your electricity rate and you have the dollar figure.
A patchwork of electricity rates
The same 12.7 kWh costs very different amounts depending on where your office is. For Anchorage and Reno we used the utility’s current small-business rate, adding up every per-kWh charge on it. Even Anchorage has two rates, depending on which part of town Chugach Electric serves you from. Georgia Power’s and APS’s small-business tariffs mix demand charges, time-of-day pricing and adjustments, so for Atlanta and Phoenix we used the state’s average commercial price from the U.S. Energy Information Administration (EIA).
| City | Rate used | Per PC per month | Per PC per year | 20-PC office per month | 20-PC office per year |
|---|---|---|---|---|---|
| Anchorage (Chugach South District) | 23.2¢/kWh, Chugach Electric small general service, effective October 2026 | $2.96 | $35 | $59 | $710 |
| Anchorage (Chugach North District) | 20.0¢/kWh, Chugach Electric small general service, effective October 2026 | $2.55 | $31 | $51 | $610 |
| Reno, Nevada | 8.9¢/kWh, NV Energy General Service (GS-1), effective October 2026, before local fees | $1.14 | $14 | $23 | $270 |
| Atlanta, Georgia | 12.5¢/kWh, Georgia state average commercial price, EIA, July 2026 | $1.60 | $19 | $32 | $380 |
| Phoenix, Arizona | 13.1¢/kWh, Arizona state average commercial price, EIA, July 2026 | $1.67 | $20 | $33 | $400 |
Per desk, it is a few dollars a month. Across an office, year after year, it adds up. An Anchorage office with 20 desktops pays more than twice what a Reno office does for the same idle hours. These are estimates; actual savings vary with your hardware, settings, how many machines already sleep, and your rate.
The objection: “But updates install overnight”
This is the main reason offices leave PCs running, and it is a fair one. Microsoft releases its monthly security updates on the second Tuesday of each month, according to its update release documentation, typically at 10 a.m. Pacific Time, and nobody wants those installing in the middle of the workday. Overnight is the natural time to install and restart.
ENERGY STAR addresses this directly. It says there is no longer a technical reason to disable power management on modern systems, because features like Wake-on-LAN (a network signal that wakes a sleeping PC) let administrators wake machines to receive updates and then let them go back to sleep.
Restarts are also becoming less frequent for some offices. As of October 2026, Microsoft offers hotpatch updates, security fixes that take effect without a restart, on eligible Windows 11 devices with certain business licenses and Microsoft’s cloud management. Even then, a restart is still needed each quarter for a “baseline” update, so a maintenance window remains useful.
So the choice is not “save power” or “stay patched.” With the right setup, you get both.
A practical power policy
- Turn on sleep for idle PCs and monitors. Set displays to sleep after a short idle period and computers after a somewhat longer one. This saves power during the day too.
- Shut down or sleep at night, on a schedule. Ask staff to save their work and log out at the end of the day. A scheduled shutdown or sleep catches the machines people forget.
- Set a maintenance window for updates. Pick one or two nights a week, timed after new patches have been held and tested, when PCs are woken to install them and restart. Outside that window, they stay off or asleep.
- Enable Wake-on-LAN where it is supported. This is a setting in the PC’s firmware and network adapter. Once it is on, a management system can wake machines remotely for updates or support.
- Keep the exceptions short and deliberate. Servers, phone systems, network equipment and any PC that must be reached remotely stay on. Everyone else follows the policy.
- Check that it works. Look at which machines actually slept, woke and patched. A policy nobody verifies tends to drift.
The environmental side
Less wasted electricity means less fuel burned to generate it, less heat for your building to remove, and less wear on fans and power supplies. In a Phoenix summer, that heat also has to be removed by air conditioning. It is one of the easier sustainability steps an office can take, and it pays for itself instead of costing money.
How FTI helps
With our managed IT service, power and update schedules work together. Our Kaseya platform can apply power settings across your PCs, and our patching process schedules updates into a maintenance window so machines are awake when they need to be and off when they do not. Our monitoring, with AI assisting our engineers, flags PCs that missed their window or are missing updates, whatever the reason, so someone follows up.
