Thermodynamics & Electrical Work

Energy & Electrical Converter

Convert mechanical, thermal, and electrical energy units between Joules, Kilowatt-hours (kWh), British Thermal Units (BTU), Calories, and Electron-volts (eV). Includes a live Ohm's Law power calculator bridging Volts, Amps, and Watts.

Power (Watts) vs. Energy (Joules / kWh)

Power is the rate at which energy is transferred per unit time: 1 Watt = 1 Joule per second. Energy is power multiplied by time: running a 1,000-Watt (1 kW) heater for one full hour consumes exactly 1 kilowatt-hour (kWh), equivalent to 3,600,000 Joules (3.6 MJ).

Small Calorie (cal) vs. Dietary Calorie (kcal)

In nutrition, what is labeled as a "Calorie" (capital C) is actually a kilocalorie (kcal), which equals 1,000 small thermochemical calories (4,184 Joules). Burning 2,000 food Calories per day means expending approximately 8.37 Megajoules of metabolic energy.