The Kilowatt Hour (kWh) is the commercial unit of electrical energy. While the SI unit of energy is the Joule (J), the Joule is too small for practical use in measuring electricity consumption. So electricity companies use the kWh, commonly called a 'unit' on electricity bills.
The kilowatt hour is abbreviated as kWh (NOT kw/h or KWH). The 'W' is always capitalized (after James Watt), and 'h' is lowercase.
1 kilowatt hour = the energy consumed by a device with a power of 1 kilowatt (1000 watts) running for 1 hour.
Conversion to Joules: 1 kWh = 1000 W × 3600 s = 3.6 × 10⁶ Joules = 3.6 MJ
This is a massive amount of energy — far too large to express in Joules for everyday billing.
Your electricity meter counts electrical energy in units (kWh):
Formula: Energy (kWh) = Power (kW) × Time (hours)
No. The SI unit of energy is the **Joule (J)**. The kWh is a practical commercial unit. 1 kWh = 3.6 × 10⁶ J.
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