Running cost comes down to wattage, hours and your rate. In Maryland the rate is 21.77 cents per kWh, which is 18.1 percent above the national average. Here is what that means for a electric water heater.
A electric water heater drawing 4,000 W costs $0.87 per hour in Maryland. Run 3 hours a day that is $2.61 daily, $78.37 a month and $954 a year, which is $146 more than the same appliance at the US average rate.
Cost by hours used per day in Maryland
| Hours/day | Energy | Per day | Per month |
|---|---|---|---|
| 1 h | 4.00 kWh | $0.87 | $26.12 |
| 2 h | 8.00 kWh | $1.74 | $52.25 |
| 4 h | 16.00 kWh | $3.48 | $104 |
| 6 h | 24.00 kWh | $5.22 | $157 |
| 8 h | 32.00 kWh | $6.97 | $209 |
| 12 h | 48.00 kWh | $10.45 | $313 |
| 24 h | 96.00 kWh | $20.90 | $627 |
Cost by wattage at 21.77 cents
| Rated power | Per hour | Per day | Per month |
|---|---|---|---|
| 3,000 W | $0.65 | $1.96 | $58.78 |
| 3,800 W | $0.83 | $2.48 | $74.45 |
| 4,500 W | $0.98 | $2.94 | $88.17 |
| 5,000 W | $1.09 | $3.27 | $97.97 |
| 5,500 W | $1.20 | $3.59 | $108 |
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.
Water heating in Maryland
Incoming groundwater temperature sets how hard the element works, and it is colder in winter everywhere. In Maryland the seasonal swing is smaller, which keeps water heating cost relatively steady through the year. A heat pump water heater cuts consumption to roughly a third and works particularly well in a warm garage.
Why Maryland pays what it does
Maryland 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 21.77 cents, Maryland ranks 37 of 51 from cheapest to most expensive. The Northeast regional average is 25.91 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 electric water heater on the same schedule, in the cheapest and dearest states:
| State | Rate | Per month | Per year |
|---|---|---|---|
| Idaho | 12.35¢ | $44.46 | $541 |
| Utah | 12.96¢ | $46.66 | $568 |
| Maryland | 21.77¢ | $78.37 | $954 |
| California | 33.25¢ | $120 | $1,456 |
| Hawaii | 52.00¢ | $187 | $2,278 |
Lowering the number in Maryland
- Set the thermostat to 120 degrees. Many ship at 140. Every 10 degrees cuts standby loss by around 4 percent.
- Insulate the first six feet of hot and cold pipe. Cheap, and it stops heat walking out through the plumbing.
- Fix dripping hot taps. A hot tap dripping once a second heats water that goes straight down the drain.
- Flush sediment annually. Sediment insulates the lower element from the water, so it runs longer.
- Consider a heat pump water heater. Roughly a third of the energy for the same hot water.
Offsetting it with solar in Maryland
This load uses about 12.00 kWh a day. Covering that would take roughly 9 standard 400 W panels at typical sun hours, an array of about 3.60 kW. Because it offsets electricity worth 21.77 cents rather than the national 18.44 cents, the same array is worth more here than the national payback figures suggest.
Water heating is the single best use of surplus solar, because the tank is a battery that stores heat instead of electrons. Diverter controllers exist specifically for this. Full sizing, including battery and inverter requirements, is on the solar sizing page for this appliance.
Questions people actually ask
[hed_faq]How much does it cost to run a electric water heater in Maryland?About $0.87 per hour and $78.37 a month at 3 hours a day, using the Maryland average rate of 21.77 cents per kWh.
How many watts does a electric water heater use?Around 4,000 W while running, with a range of roughly 3,000 to 5,500 W depending on model and setting.
Is that expensive for Maryland?Maryland electricity runs 18.1 percent above the national average, so this appliance costs $146 more per year here than it would at the US average rate.
Can I lower this without replacing the appliance?Usually yes. Run time is the variable you control, and the hours table above shows exactly what each hour costs. In Maryland you can also shop for a cheaper supply rate, which lowers every figure on this page proportionally.[/hed_faq]