How much does a desktop computer cost to run in Maine?

$8.64 a month

A day of use
$0.28
An hour of running
$0.04
A year
$103.68

120 W, 8 hours a day (tower only, no monitor), at Maine’s average rate of 29.6¢ per kWh (EIA, June 2026). How we calculate this

Change the watts, hours or rate
I know the appliance's

What it costs at other usage levels

Desktop computer at 120 W and 29.6¢ per kWh
UseA dayA monthA year
1 hour a day$0.04$1.08$12.96
2 hours a day$0.07$2.16$25.92
4 hours a day$0.14$4.32$51.84
8 hours a day typical$0.28$8.64$103.68
24 hours a day$0.85$25.92$311.05
Monthly cost of a desktop computer in Maine, nearby states and the USMaine: $8.64; New Hampshire: $7.89; US average: $5.36Maine$8.64New Hampshire$7.89US average$5.36

A typical model draws about 120 W (Virginia Cooperative Extension).

Maine compared with other states

CheapestMost expensive

Maine’s residential rate is the 4th most expensive of 51 states and DC, 11.3¢ above the US average of 18.3¢ (+61%). Maine’s rate is up 1.5¢ from June 2025 (28.1¢, +5.2%).

A cheaper way to do the same job

Ways to spend less

  • Set it to sleep after 15 minutes idle.
  • Shut it down at night instead of leaving it on.
  • For email and browsing, a laptop does the same job on much less power.

Questions

How much does it cost to run a desktop computer per hour?

About $0.04 an hour in Maine. A desktop computer at 120 W uses 0.120 kWh per hour, and at Maine’s average of 29.6¢ per kWh that comes to $0.04.

How much does a desktop computer add to your electric bill?

Used 8 hours a day (tower only, no monitor), about $8.64 a month in Maine, or $103.68 a year.

How much does it cost to run a desktop computer 24 hours a day?

Running nonstop, a desktop computer would use 2.88 kWh a day and cost $0.85 a day, or $25.92 over an average month in Maine.

How many watts does a desktop computer use?

A typical model draws about 120 W (Virginia Cooperative Extension). Check the label on yours: cost scales directly with watts, so a 20% lower wattage means a 20% lower bill.

Is it cheaper to run a desktop computer or a laptop?

Using a laptop for the same hours instead would cost about $3.60 a month instead of $8.64, saving $5.04 in Maine.

Why does a desktop computer cost more or less to run in Maine than elsewhere?

Maine’s residential rate is the 4th most expensive of 51 states and DC, 11.3¢ above the US average of 18.3¢ (+61%). Maine’s rate is up 1.5¢ from June 2025 (28.1¢, +5.2%). The appliance uses the same energy everywhere; only the price per kWh changes.

Sources

Usage assumptions (hours a day, season) are ours and listed on the methodology page. Found an error? Tell us.