LED and appliance savings: what actually saves
DOE says lighting is about 15% of an average home's electricity use and that LEDs use up to 90% less energy. On this site's 2025 figure of 878 kWh a month for the average home, 15% is about 1,580 kWh a year, or $273 at 17.30 cents. The rest of the bill is bigger.
The one formula
DOE Energy Saver gives three steps. Daily kWh equals watts times hours used per day, divided by 1,000. Annual kWh equals daily kWh times days used. Annual cost equals annual kWh times your price per kWh. DOE's own example is a 1,500 W kettle used 1 hour a day: 547.5 kWh a year.
The formula needs two inputs you control: watts and hours. A bulb has low watts and many hours. An oven has high watts and few hours. A refrigerator has modest watts, but DOE says it cycles on and off, so to estimate the hours it truly runs at full power, divide the time it is plugged in by three. That is why labels give yearly kWh for fridges instead of watts.
What an LED swap is worth
Take our scenario: one 60 W bulb that runs 3 hours a day. It uses 65.7 kWh a year. DOE says LEDs use up to 90% less energy, so an LED that cuts 90% uses 6.6 kWh and the swap saves 59.1 kWh. At the U.S. average home price that is $10.23 a year for one bulb.
| Step (our scenario) | Arithmetic | Energy | Cost at 17.30 cents |
|---|---|---|---|
| Old bulb: 60 W | 60 x 3 / 1,000 x 365 | 65.7 kWh | $11.37 |
| LED at 90% less energy | 65.7 x (1 - 0.90) | 6.6 kWh | $1.14 |
| Saved by one bulb | difference | 59.1 kWh | $10.23 |
| Saved by 20 bulbs | 20 x one bulb | 1,183 kWh | $204.59 |
Our scenario, not a measurement: a 60 W bulb on 3 hours a day all year. The formula is DOE Energy Saver's; the 90% is DOE's 'up to' figure for LEDs, so real savings can be lower. Price: EIA retail sales, 2025.
DOE puts the average household saving from LED lighting at about $225 a year. Our twenty-bulb scenario gives $205 at the national price. The two are not meant to match: DOE's figure is an average over homes with many different bulbs and hours, ours is one made-up house. Count your own bulbs and hours before you trust either one.
Where the saving is biggest
Price multiplies every kWh. The same twenty bulbs save $140 a year in North Dakota, where the 2025 home price is 11.81 cents, and $480 in Hawaii at 40.59 cents. Find your state's price on its page, for example the Texas hub or the California hub.
| State | Home price 2025, cents per kWh | Saving from 20 LED bulbs a year (scenario) | Gap between a 90th and 10th percentile refrigerator a year |
|---|---|---|---|
| North Dakota | 11.81 | $140 | $46 |
| Idaho | 11.82 | $140 | $46 |
| Nebraska | 12.34 | $146 | $48 |
| Louisiana | 12.57 | $149 | $49 |
| Arkansas | 12.84 | $152 | $50 |
| Montana | 12.98 | $154 | $50 |
| Hawaii | 40.59 | $480 | $157 |
| California | 32.54 | $385 | $126 |
| Massachusetts | 30.48 | $360 | $118 |
| Rhode Island | 29.46 | $348 | $114 |
| Connecticut | 29.38 | $347 | $114 |
| Maine | 27.78 | $329 | $108 |
Source: EIA retail sales, 2025; DOE Energy Saver formula; ENERGY STAR refrigerator percentiles. First six rows are the lowest-price states, last six the highest. Retrieved 2026-10-02. CSV, 51 rows.
Appliances: what ENERGY STAR data shows
ENERGY STAR publishes a yearly kWh for each certified model. We downloaded the lists on 2 October 2026 and took the median of each. A median certified refrigerator uses 457 kWh a year across 2,980 models, which costs $79 at the U.S. price. A median certified electric dryer uses 608 kWh, and a heat pump water heater 1,181 kWh.
United States, Yearly cost to run the median ENERGY STAR model at the U.S. average home price: EIA retail sales.
CSV| Appliance | Certified models | Median kWh a year | Cost a year at 17.30 cents | 10th to 90th percentile, kWh | Cost of the gap between them | Median of Most Efficient models, kWh |
|---|---|---|---|---|---|---|
| Heat pump water heater | 601 | 1,181 | $204 | 846 to 1,387 | $94 | No data |
| Electric clothes dryer | 477 | 608 | $105 | 266 to 608 | $59 | 154 |
| Room air conditioner | 523 | 532 | $92 | 375 to 900 | $91 | 532 |
| Refrigerator, full size | 2,980 | 457 | $79 | 297 to 685 | $67 | 363 |
| Freezer, full size | 506 | 438 | $76 | 355 to 526 | $29 | 385 |
| Dehumidifier | 559 | 340 | $59 | 181 to 526 | $60 | 257 |
| Dishwasher | 761 | 239 | $41 | 220 to 240 | $3 | 220 |
| Electric range or cooktop | 260 | 195 | $34 | 188 to 195 | $1 | No data |
| Television | 183 | 184 | $32 | 66 to 320 | $44 | No data |
| Air purifier | 247 | 152 | $26 | 55 to 346 | $50 | 87 |
| Clothes washer | 412 | 110 | $19 | 75 to 170 | $16 | 99 |
| Desktop computer | 428 | 48 | $8 | 22 to 85 | $11 | No data |
| Computer monitor | 1,588 | 45 | $8 | 32 to 91 | $10 | No data |
| Laptop | 1,197 | 13 | $2 | 9 to 19 | $2 | No data |
Source: ENERGY STAR Certified Products open data (data.energystar.gov), downloaded retrieved 2026-10-02, one file per product; kWh a year is the figure each maker lists. Price: EIA retail sales, 2025, 17.30 cents per kWh. Median of the certified list is not the average home's own appliance. Retrieved 2026-10-02. CSV, 14 rows.
Look at the spread, not only the median. Among the 2,980 refrigerators, the 10th percentile uses 297 kWh and the 90th uses 685 kWh. The gap of 388 kWh is worth $67 a year at the U.S. price, every year the fridge runs. Two certified models can differ more than a certified one and an old unit that lacks the label.
Order your effort
Rank by kWh, not by hassle. Light bulbs are cheap to change but each one is small. The big loads in the table are water heating, dryers, refrigerators and dehumidifiers. The ENERGY STAR median of a heat pump water heater, 1,181 kWh, is larger than the median refrigerator because hot water is a big job. The question for a water heater is what it replaces, which this page cannot answer.
Cheap first steps: switch remaining incandescent bulbs, check your refrigerator's label, and use a plug-in meter. DOE says electricity usage monitors cost around $25-$50 and work on 120-volt devices, not on 240-volt ones such as clothes dryers. DOE also notes that many devices draw standby power when 'off' and that a power strip with a switch cuts it. This page has no data on how many watts standby draws: no data.
What this page cannot tell you
The ENERGY STAR lists show what makers certify, not what is in your house. Your older fridge might use more than the 90th percentile of new models. We have no data on appliance age by home, on purchase prices, or on rebates by utility, so there is no payback figure here. The LED example is a scenario and says so. For exact numbers, read the EnergyGuide label on the appliance or measure with a plug-in meter.
Related tools
Use the appliance running cost pages to see the same ENERGY STAR medians by state, the watts calculator for any device, and all tools. Terms are in the glossary. Sources are on the data sources page.
Key facts and where they come from
| Fact | Value | Source | Date |
|---|---|---|---|
| Lighting share of average home electricity use | Around 15% | DOE Energy Saver, Lighting Choices to Save You Money | retrieved 2026-10-02 |
| Average household saving from LED lighting | About $225 a year | DOE Energy Saver, Lighting Choices to Save You Money | retrieved 2026-10-02 |
| LED energy use against incandescent | Up to 90% less | DOE Energy Saver, Lighting Choices to Save You Money | retrieved 2026-10-02 |
| DOE worked example, 1,500 W kettle, 1 hour a day | 547.5 kWh a year | DOE Energy Saver, Estimating Appliance and Home Electronic Energy Use | retrieved 2026-10-02 |
| Price of an electricity usage monitor | Around $25-$50 | DOE Energy Saver, Estimating Appliance and Home Electronic Energy Use | retrieved 2026-10-02 |
| U.S. home price | 17.30 cents per kWh | EIA retail sales, 2025 | 2025 annual |
| Average home use, U.S. | 878 kWh a month | EIA monthly sales 2025 | 2025 |
| 15% of average home use, per year (computed) | 1,580 kWh | DOE share times EIA monthly sales 2025 | 2025 |
| Median certified refrigerator, full size | 457 kWh a year (2,980 models) | ENERGY STAR Certified Products, data.energystar.gov | retrieved 2026-10-02 |
| Median certified electric dryer | 608 kWh a year (477 models) | ENERGY STAR Certified Products | retrieved 2026-10-02 |
| Median certified heat pump water heater | 1,181 kWh a year (601 models) | ENERGY STAR Certified Products | retrieved 2026-10-02 |
| Our scenario: one 60 W bulb, 3 hours a day | 65.7 kWh a year | DOE formula applied to assumed inputs | scenario |
| Our scenario: saving from one LED at 90% less | 59.1 kWh a year | Computed from the line above | scenario |
Keep reading
Questions
How much does an LED bulb save?
In our scenario of a 60 W bulb used 3 hours a day, an LED that uses 90% less saves 59.1 kWh a year, or $10.23 at the 17.30 cent U.S. price. DOE says LEDs use up to 90% less, so treat this as the top end.
What share of my electricity is lighting?
DOE says lighting is around 15% of an average home's electricity use. On this site's 878 kWh a month average, that is about 1,580 kWh a year.
How do I work out what any device costs?
Use DOE's formula: watts times hours a day divided by 1,000 gives daily kWh, times days used gives yearly kWh, times your price per kWh gives the cost. DOE's kettle example is 547.5 kWh a year.
How much does a refrigerator cost to run?
The median of 2,980 ENERGY STAR full-size models is 457 kWh a year, $79 at 17.30 cents.
Is it worth replacing a working appliance?
This page has no payback data. It shows the spread among certified refrigerators: 388 kWh a year between the 10th and 90th percentile, about $67 at the U.S. price. Compare that with the price of a new unit.
How can I measure a device myself?
DOE says an electricity usage monitor costs around $25-$50 and works on devices that run on 120 volts. It does not work on 240-volt appliances such as dryers.
Which state saves the most from LEDs?
For our twenty-bulb scenario, Hawaii: $480 a year at 40.59 cents, against $140 in North Dakota.
Where do the appliance numbers come from?
ENERGY STAR Certified Products open data from data.energystar.gov, downloaded 2 October 2026, and DOE Energy Saver pages retrieved the same day.
Space heaters
Of the plug-in devices people ask about, a heater draws the most. Space heater cost per hour and month.