The total distribution loss is the difference between the energy input into the feeder and the total energy billed to the consumer. The formula is as follows:

T&D Losses (%) = [(Energy Input (kWh) - Billed Energy (kWh)) / Energy Input (kWh)] x 100

While this formula provides a high-level overview, a more detailed calculation for technical losses, particularly the variable losses, uses the fundamental principle of Joule's Law. The power loss (Ploss) in a conductor is calculated as:

Ploss=I2R

Where:

• I is the current flowing through the conductor.

• R is the resistance of the conductor.

For a comprehensive calculation over a period, factors like the load factor (LF) and loss load factor (LLF) are used. The LLF accounts for the variation in losses due to fluctuating loads over time and can be approximated using the LF with the following formula:

LLF = (0.8 x LF2) + (0.2 x LF)

These formulas are critical for engineers and utility companies to accurately model and manage network losses.