Router and Home Network Electricity Cost: What to Count

Start with a simple inventory

Record each separately powered item and whether your measurement includes anything it powers. An example network might have a 10 W router, an 8 W fiber terminal, and a 12 W switch-and-access-point group.

The total is 30 W. At 24 hours a day, it uses 0.72 kWh daily, or 262.8 kWh annually. At an illustrative 18¢/kWh, that is $3.95 per average month and $47.30 per year. These numbers describe an invented setup, not typical consumption for those device classes.

In the calculator, add the separately measured groups as individual entries. For a stable all-day measurement, use the same active and idle watts and set total hours to 24.

Count PoE-powered devices once

Power over Ethernet supplies a compatible connected device through its network connection. When a measurement is taken at a PoE switch’s wall input, the reading includes the power drawn from that input to supply its connected PoE loads.

If the example 12 W reading already covers the switch and one access point, do not add a second entry for that access point. If the access point has its own separate power supply or injector outside the measured group, include that supply separately.

A switch’s PoE budget describes the power it can distribute; it is not a measurement of what your configuration consumes all day. Use the specifications for compatibility and capacity planning, and use a representative measurement for the running-cost estimate.

Whole-group readings simplify the total

If an existing suitable monitoring arrangement reports total network kWh, it can capture the combined usage without reconstructing every component. Label the result “whole network” and keep its individual component measurements out of the same total.

If the network is supplied through a UPS, decide whether your reading is upstream or downstream of it. UPS input includes an additional source of consumption that should not be added twice.

Check the size of a possible saving

Reducing the average load by 5 W for the entire year saves 43.8 kWh. At 18¢/kWh, that is $7.88 per year. A $100 replacement bought solely for that reduction would take about 12.7 years to pay for itself from electricity.

That calculation leaves out other benefits and costs. Coverage, capacity, reliability, and device support may matter more than a small energy saving. Compare the full purchase cost and the services the replacement must provide.

Keep needed services in the schedule

Before assuming a network can shut down overnight, consider remote access, calls, monitoring, backups, and other equipment that relies on it. Model only the hours you can actually avoid. A 24-hour estimate is appropriate when availability throughout the day is part of the job.