Power Loss (I²R)

Every wire has resistance. When current flows, power is lost as heat. Over long industrial cable runs operating 24/7, this I²R loss translates directly to wasted electricity and increased HVAC load.

The Formula

P = I² × R

• P: Power lost in Watts
• I: Current in Amperes
• R: Total resistance of the wire run in Ohms (round trip)

Financial Impact Example

Consider a 200ft run carrying 100 Amps continuously for a year (8760 hours).

• Using 2 AWG (0.032Ω): Loss is 100² × 0.032 = 320W. Over a year: 2,803 kWh.
• Using 1/0 AWG (0.020Ω): Loss is 100² × 0.020 = 200W. Over a year: 1,752 kWh.

Upsizing the cable saves 1,051 kWh annually. At $0.15/kWh, that's $157 saved per year, often paying for the thicker cable within 24 months.