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

$4.65 a month

A day of use
$0.15
An hour of running
$0.02
A year
$55.82

120 W, 8 hours a day (tower only, no monitor), at Iowa’s average rate of 15.9¢ per kWh (EIA, June 2026). How we calculate this

Change the watts, hours or rate
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What it costs at other usage levels

Desktop computer at 120 W and 15.9¢ per kWh
UseA dayA monthA year
1 hour a day$0.02$0.58$6.98
2 hours a day$0.04$1.16$13.95
4 hours a day$0.08$2.33$27.91
8 hours a day typical$0.15$4.65$55.82
24 hours a day$0.46$13.95$167.46
Monthly cost of a desktop computer in Iowa, nearby states and the USIowa: $4.65; Illinois: $5.81; Minnesota: $5.12; Missouri: $4.74; Nebraska: $3.87; South Dakota: $4.49; US average: $5.36Iowa$4.65Illinois$5.81Minnesota$5.12Missouri$4.74Nebraska$3.87South Dakota$4.49US average$5.36

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

Iowa compared with other states

CheapestMost expensive

Iowa’s residential rate is the 23rd cheapest of 51 states and DC, 2.4¢ below the US average of 18.3¢ (−13%). Iowa’s rate is up 0.6¢ from June 2025 (15.3¢, +3.9%).

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 $0.02 an hour in Iowa. A desktop computer at 120 W uses 0.120 kWh per hour, and at Iowa’s average of 15.9¢ per kWh that comes to $0.02.

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

Used 8 hours a day (tower only, no monitor), about $4.65 a month in Iowa, or $55.82 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 $0.46 a day, or $13.95 over an average month in Iowa.

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 $1.94 a month instead of $4.65, saving $2.71 in Iowa.

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

Iowa’s residential rate is the 23rd cheapest of 51 states and DC, 2.4¢ below the US average of 18.3¢ (−13%). Iowa’s rate is up 0.6¢ from June 2025 (15.3¢, +3.9%). 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.