The washing machine is mostly a motor-and-water story; a clothes dryer is usually a heat story first. Full-size electric dryers lean on a ~240 V branch and a large resistive element. Gas models burn fuel for heat and use the wall for drum, controls, and blower. Heat-pump dryers run a lower average W for a longer time—check kWh per load, not just a peak W figure.
How to calculate kWh from watts and hours and Daily off-grid use in Wh turn minutes into kWh. Generator running watts vs starting watts matters when a tumbler lines up with a refrigerator or microwave in an outage. Compare other big thermal loads in water heater and space heater rows. Stack everything in the WattSizing calculator.
1) Running W by class (illustrative; nameplate + breaker win)
| Type | Ballpark running W | Notes |
|---|---|---|
| Gas (drum + controls + fan) | ~400–900 | 120 V; fuel carries most of the heat |
| 120 V compact electric | ~1,200–1,800 | Often a 15 A class story—NEC + nameplate |
| Heat-pump | ~600–1,500 | Longer cycles; condenser care |
| Standard 240 V electric | ~4,000–5,500+ | Element dominates; drum is hundreds of W |
Boost, sanitize, or “extra dry” modes can bump W—read the sticker for the mode you use.
2) Where the watts go
- Electric resistive: highest W when the element is on; blower, drum motor, and electronics add on top.
- Gas: mains W is mostly tumbler, blower, controls, and small ignition or valve loads—Btu/h of gas is not watts at the cord.
- Heat-pump: compressor + fans at moderate W; time in the drum sets kWh.
3) 240 V, 30 A class, and your panel
A conventional electric dryer is often a ~30 A branch (overcurrent + nameplate state the truth) on 120/240 V with L1, L2, and neutral for mixed 120/240 loads. That is a different branch class than a window AC plug or a central AC outdoor unit—stagger big thermal loads in time, not in one imagined “total W” napkin.
4) kWh: two paths to the same bill
Example: 5,000 W heating + motor stack for 0.5 h ≈ 2.5 kWh—kWh from watts and hours. A 1,200 W heat-pump average for 1.5 h is 1.8 kWh—lower W can still be meaningful kWh if the run is long. Your retail $/kWh lives in your utility contract; EIA electricity explained is a neutral U.S. anchor.
5) Generators: gas dryer vs 240 V electric
- Gas dryer: often in range of a small portable for the motor surge story—still add fridge and router honestly in running vs starting totals.
- 120 V compact electric: check continuous W against the gen you own; cord and receptacle matter.
- 240 V standard electric: you need a unit with a correct listed 240 V outlet, continuous headroom for the element, and margin for overlap with well pump or fridge if those are on the same backup design. Do not assume a 5 kW portable comfortably runs a 5 kW-class dryer plus the rest of the list.
U.S. DOE portable generators: outdoors, listed transfer, no backfeed.
6) Lint, venting, and sensors (kWh and safety)
Clogged lint paths and crushed ducts extend run time—more kWh and a real fire-path risk. Moisture-sensing auto cycles (with a clean lint path) usually beat blind “90 min timed dry.” A higher spin on the washer puts less water in the drum and can shrink dryer kWh without new hardware.
FAQs
Why do electric dryers use 240 V?
Two hots feed a large resistive load at manageable current; many designs also need 120 V for controls and some motor sections. 3- vs 4-prong evolution is a safety / ground topic for a licensed electrician, not a blog guess.
Is a gas dryer “free” electricity?
No. Fuel carries the heat; you still pay hundreds of watts at the plug plus the gas line item.
How many kWh is one 45 min electric cycle at 5,000 W?
5,000 × (45/60) ÷ 1,000 = 3.75 kWh if the element plus blower stack is ~5,000 W the whole time—kWh from watts and hours; real cycles taper as clothes dry, so measured time wins.
Can a 5,000 W generator run a full-size 240 V electric dryer?
Usually not a reliable “dryer + rest of the house” plan at 5 kW class; a gas dryer, compact 120 V unit, or staggering loads is the common outage story—see running vs starting for what else is on.
Does a heat-pump dryer always save kWh vs standard electric?
Often on kWh per load if filters and the condenser path are maintained; a neglected path can erase the edge. Compare kWh per load with a submeter or utility data, not a headline W.
Should I add dryer W to the same add list as an electric range in an outage?
Stagger. Two large thermal loads in the same moment is how portables stall—build a running vs starting list you can actually run.
Is off-grid split-phase 240 V “easy” for a standard electric dryer?
Usually expensive in inverter and Ah; gas, heat-pump, or line-drying is often a kinder daily Wh story. Pure sine is the safer default for small motors on the same AC as electronics.
Recap: know heat type (gas vs 120 V vs 240 V vs heat-pump), then W and minutes to kWh with kWh from watts and hours; add generator overlap for outages. Enter rows in the WattSizing calculator.
