Running cost comes down to wattage, hours and your rate. In Illinois the rate is 23.85 cents per kWh, which is 29.3 percent above the national average. Here is what that means for a microwave oven.
A microwave oven drawing 1,000 W costs $0.24 per hour in Illinois. Run 0.5 hours a day that is $0.12 daily, $3.58 a month and $43.53 a year, which is $9.87 more than the same appliance at the US average rate.
Microwave oven cost at Illinois rates
Change any box. The result updates as you type.
Planning estimate. The rate box is prefilled with a regional average; the figure on your own bill is the one that matters. Power is draw while running, not while switched on.
Cost by hours used per day in Illinois
| Hours/day | Energy | Per day | Per month |
|---|---|---|---|
| 1 h | 1.00 kWh | $0.24 | $7.16 |
| 2 h | 2.00 kWh | $0.48 | $14.31 |
| 4 h | 4.00 kWh | $0.95 | $28.62 |
| 6 h | 6.00 kWh | $1.43 | $42.93 |
| 8 h | 8.00 kWh | $1.91 | $57.24 |
| 12 h | 12.00 kWh | $2.86 | $85.86 |
| 24 h | 24.00 kWh | $5.72 | $172 |
Cost by wattage at 23.85 cents
| Rated power | Per hour | Per day | Per month |
|---|---|---|---|
| 600 W | $0.14 | $0.07 | $2.15 |
| 800 W | $0.19 | $0.10 | $2.86 |
| 1,000 W | $0.24 | $0.12 | $3.58 |
| 1,200 W | $0.29 | $0.14 | $4.29 |
| 1,800 W | $0.43 | $0.21 | $6.44 |
Find the row matching the nameplate on your own unit. Within a single appliance category the spread is often wider than the difference between categories, so the label is worth reading.
A load climate does not touch
Microwave use is one of the few loads on this site that climate has essentially no effect on. The figure above is close to a flat national constant adjusted only for Illinois’s own electricity rate, unlike heating or cooling appliances where the season changes the picture substantially.
Why Illinois pays what it does
Illinois has a competitive retail electricity market, so the rate used here blends households on the utility default with households on shopped supply plans. If you have never switched supplier you are probably on the default, which is usually the more expensive side of that blend. Only the generation portion of your bill changes when you switch; delivery and outage response do not.
At 23.85 cents, Illinois ranks 40 of 51 from cheapest to most expensive. The Midwest regional average is 16.55 cents. Roughly half of any residential bill is transmission and distribution rather than generation, which is why rates keep climbing even when fuel prices fall.
How this compares across the country
The same microwave oven on the same schedule, in the cheapest and dearest states:
| State | Rate | Per month | Per year |
|---|---|---|---|
| Idaho | 12.35¢ | $1.85 | $22.54 |
| Utah | 12.96¢ | $1.94 | $23.65 |
| Illinois | 23.85¢ | $3.58 | $43.53 |
| California | 33.25¢ | $4.99 | $60.68 |
| Hawaii | 52.00¢ | $7.80 | $94.90 |
Lowering the number in Illinois
- Use it instead of the oven for small portions. Heating a small cavity for a few minutes beats heating a full oven cavity for much longer.
- Cover food to retain heat and moisture. Uncovered food often needs longer cook times to reach the same result.
- Keep the door seal clean. A poor seal can extend cook times and, over the long run, is also a safety concern.
Offsetting it with solar in Illinois
This load uses about 0.50 kWh a day. Covering that would take roughly 1 standard 400 W panels at typical sun hours, an array of about 0.40 kW. Because it offsets electricity worth 23.85 cents rather than the national 18.44 cents, the same array is worth more here than the national payback figures suggest.
Very short runtime makes the daily energy small even though the draw looks large. Panels rarely need to change for a microwave. Full sizing, including battery and inverter requirements, is on the solar sizing page for this appliance.