Electricity usage is calculated in kilowatt-hours. A kilowatt-hour is 1,000 watts used for one hour. As an example, a 100-watt light bulb operating for ten hours would use one kilowatt-hour.
How to calculate electric usage cost:
1. Volts x Amps = Watts
2. Watts ÷ 1,000 = Kilowatts (kW)
3. Kilowatts (kW) x Hours of Use = Kilowatt Hours (kWh)
4. Kilowatt Hours (kWh) x kWh rate = Cost of Usage
5. Add TVA Energy Fuel Cost charge per kWh
Below are some examples of electrical appliances found in most homes. These examples are using an 11 cents per kWh rate and are based on a 1,800 sq.ft. home.
| Appliance/Equipment | Avg. Daily Usage | Monthly kWh (31 Days) | Approximate Cost/Month |
|---|---|---|---|
| Comfort & Health | |||
| Air Conditioner – Window 12,000 BTU (1,400 W) |
12 hours/day | 521 | $57.29 |
| Portable Dehumidifier (600 W - 50 Pint) | 12 hours/day | 223 | $24.55 |
| Portable Humidifier (50 W) | 12 hours/day | 19 | $2.05 |
| Fan – Furnace - 1/2 HP (400 W) | 12 hours/day | 149 | $16.37 |
| Fan – Ceiling - 60" (100 W) | 12 hours/day | 37 | $4.09 |
| Heat Pump - Heating 30,000 BTUh 7.5 HSPF* |
varies | 8,439 annually | $950.00 annually |
| Heat Pump - Cooling 30,000 BTUh 14.3 SEER** |
varies | 3,625 annually | $399.00annually |
| *Heating Season Performance Factor (an efficiency rating) Seasonal Energy Efficiency Ratio |
|||
| Space Heater – Portable (1500 W) | 12 hours/day | 558 | $61.00 |
| Water Heater Standard 50 gal (4,500 W) | 3 hours/day | 419 | $46.04 |
| Kitchen | |||
| Toaster Oven (1,200 W) | 1 hour/week | 37 | $4.09 |
| Coffee Maker (900 W) | one hour/day | 28 | $3.07 |
| Dishwasher (1,200 W) | one hour/day | 37 | $4.09 |
| Microwave Oven (1,000 W) | 1 hour/day | 31 | $3.41 |
| Oven (2,300 W) | 1 hour/day | 71 | $7.84 |
| Cooktop (1,000 W) | 1 hour/day | 31 | $3.41 |
| Upright Freezer (175 W) | 12 hrs/day | 65 | $7.16 |
| Refrigerator/Freezer – (150 W, 22 cu ft) | 12 hrs/day | 56 | $6.14 |
| Laundry | |||
| Clothes Dryer (3,400 W) | 1 hr/day | 105 | $11.59 |
| Washer (290 W) |
1 hr/day | 9 | $.99 |
| Iron (1,000 W) |
1 hr/day | 31 | $3.41 |
| Home Entertainment/Recreation | |||
| 42″ TV - 42" Plasma (in use) | 5 hours/day/td> | 50 | $5.51 |
| 42″ TV - 42" LCD (in use) | 5 hours/day | 24 | $2.68 |
| DVD Player(in use) | 2 hours/week | 4 | $0.44 |
| High-Definition Gaming (in use) | 2 hours/week | 12 | $1.33 |
| Desktop Computer w/LCD Monitor (in use) | 4 hours/day | 27 | $3.00 |
| Cable TV Set-Top Box (26 W) | 24 hours/day | 19 | $2.13 |
| Router (25 W) | 24 hours/day | 18 | $2.05 |
| Ink-Jet Printer (in use) | 1 hour/day | 5 | $0.5 |
| Leisure | |||
| Hot Tub (5,000 W) | 2 hours/day | 310 | $34.10 |
| Pool Pump (1 hp) | continuous | 1116 | $122.76 |
| General | |||
| Clock Radio (4W) | 12 hours/day | 1.49 | $0.16 |
| Vacuum (1200 W) | 10 minutes | 6 | $0.68 |
| Hair Dryer (1,600W) | 20 minutes | 18 | $1.78 |
| Lighting | |||
| Incandescent (60 W) | 4 hours/day | 7.4 | $0.82 |
| LED 60 W Equivalent (9 W) | 4 hours/day | 1.1 | $0.12 |
| Incandescent (75 W) | 4 hours/day | 9.3 | $1.02 |
| LED 75 W Equivalent (12 W) | 4 hours/day | 1.5 | $0.16 |
| Incandescent (100 W) | 4 hours/day | 12.4 | $1.36 |
| LED 100 W Equivalent (17 W) | 4 hours/day | 2.1 | $0.23 |
| Farm | |||
| Livestock Tank Heater (1,200 W) | 12 hours/day | 446 | $49.10 |
| Livestock/Poultry Heat Lamp (250 W) | 24 hours/day | 186 | $20.46 |
| Tractor Engine Block Heater (600W) | 12 hours/day | 223 | $24.55 |
| Electric Fence Charger (33W) | 0-1 hours/day | 1 | $.11 |
| Well Pump (1,000 W) | 1 hour/day | 31 | $3.41 |
| Electric Vehicle | Electric Vehicle Charger* (7,200 W) | 2 hours/day | 437 | $48.05 |
| *An electric vehicle will travel 40 miles on a 2-hour charge or 280 miles per week when charging for 2 hours daily. | |||