# kWh

/ˈkeɪˈdəbəɫjuˈeɪtʃ/ (US) · CEFR B2 · Noun

Source: https://englishreference.com/word/kwh
Updated: 2026-05-08

## Definition

a unit of energy that measures how much electricity you use. It is the amount of power used by a 1,000-watt appliance running for one hour.

For teachers: a unit of energy equivalent to one kilowatt of power sustained for one hour. Used as a standard billing unit for energy delivered to consumers by electric utilities.

## Examples

- My electricity bill shows how many kWh I used this month.
- Switching to LED bulbs can significantly reduce the total number of kWh consumed by a household each year.
- The battery capacity of modern electric vehicles is typically measured in kWh, determining the total distance the car can travel on a single full charge under standard conditions.

## Pitfalls

- Not "The heater uses 2 kWh per hour." but "The heater uses 2 kW." — Learners often confuse kWh (total energy) with kW (power/rate). A 2 kW heater uses 2 kWh of energy if left on for exactly one hour.

## Usage notes

- Often written without a plural 's' (e.g., '50 kWh') in technical contexts, though 'kWhs' is sometimes seen in informal writing.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.