Model
Lg DLG3421*
Rank #447 means 446 of the 615 clothes dryer models we track cost less to run each year; the 21st efficiency percentile means it uses less energy for its size than 21% of those models.
What does the Lg DLG3421* cost to run per year?
Among the 615 clothes dryer models we track, the Lg DLG3421*'s $127/yr running cost ranks it #447, in the above-average-cost group. Efficiency-wise, once size is accounted for, it trails most of the class, ahead of only 21% of the models we track. Its CEF of 3.49 reflects combined energy factor, one of the class's core efficiency levers.
Immediately around it on the leaderboard, the Lg DLGX5801* at $127/yr runs a little cheaper and the Lg DLG3581* at $127/yr runs a little more, a sense of how tightly models are packed at this point in the ranking. A clothes dryer typically stays in service for somewhere around 13 years; over that span, the Lg DLG3421*'s $127/yr adds up to roughly $1651 in electricity alone, before purchase price or repairs.
Also sold as: Lg DLG1502*.
By the numbers
The Lg DLG3421* normalized against its whole class, so each figure means something.
What it costs you over time
Running cost is an every-year number, so it compounds. At $127/yr, here is what the Lg DLG3421* adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Lg DLG3421* costs about $1270. That is roughly $140 more than the class median, which would run closer to $1130 over the same ten years.
How the Lg DLG3421* compares
The clothes dryer class we track runs from $23 to $128 a year. At $127/yr, it runs about $14 a year above the class median of $113, and it is about $104 a year more than the cheapest clothes dryer to run at $23.
What drives its running cost
At 7.4 cu ft, the Lg DLG3421* is a small clothes dryer for its class, which spans 3.8 to 9.2 cu ft with a median of 7.4 cu ft, and smaller clothes dryer models generally cost less to run for the same job, all else being equal. Its CEF of 3.49, below the class median of 3.93, reflects combined energy factor: a higher figure means it wrings more useful work out of every kilowatt-hour, so it is the efficiency lever to weigh against raw size.
- Heat source and Combined Energy Factor (CEF). Heat-pump dryers recycle heat instead of generating it fresh with a resistance coil, and typically use meaningfully less electricity per load than a conventional resistance dryer, at the cost of a longer cycle; CEF is the federal figure that captures this.
- Drum capacity. A larger drum can dry a bigger load per cycle, but it also usually needs more energy per cycle to heat the extra air volume.
Common questions
Is the Lg DLG3421* cheap to run?
Its $127/yr running cost, rank #447 of 615, is above what most clothes dryer models we track cost to run, so this is not one of the cheaper picks on electricity alone.
How much does the Lg DLG3421* cost per month?
About $10.59 a month, which is the $127 annual estimate spread across twelve months at the US average rate of $0.1856/kWh. Your own bill scales with your local electricity rate and how heavily you use it.
How is this running-cost figure calculated?
The formula is annual kWh times price per kWh: 685 kWh from ENERGY STAR times the US average of $0.1856/kWh comes to about $127 a year. It covers electricity only, not the purchase price, water, or installation.
How efficient is the Lg DLG3421* for its size?
21st percentile once size is factored in. That means its size-adjusted efficiency is not the main reason for the running-cost figure above; its capacity plays a large role too.
Cheaper to run in the same class
| Rank | Model | Cost/yr |
|---|---|---|
| 510 | Lg DLGX5801*7.4 cu ft | $127 |
| 509 | Lg DLG8201*7.3 cu ft | $127 |
| 508 | Lg Signature DLGX9901*9 cu ft | $127 |
| 507 | Lg DLG8481*E7.3 cu ft | $127 |
| 506 | Lg DLGX8601*E7.3 cu ft | $127 |
Source
ES_1118034_DLG3421*_09152025164527_80269413View certified clothes dryer listingsENERGY STAR data as of July 2026Lg and DLG3421* are used here for identification only and are not endorsements. Figures are computed by WattWise Labs from public ENERGY STAR data, not measured in our own lab.