Technical Losses:

The technical losses are due to energy dissipated in the conductors, equipment used for transmission Line, Transformer, sub- transmission Line and distribution Line and magnetic losses in transformers.

Technical losses are normally 22.5%, and directly depend on the network characteristics and the mode of operation.

The major amount of losses in a power system is in primary and secondary distribution lines. While transmission and sub-transmission lines account for only about 30% of the total losses. Therefore the primary and secondary distribution systems must be properly planned to ensure within limits.

The unexpected load increase was reflected in the increase of technical losses above the normal level

Losses are inherent to the distribution of electricity and cannot be eliminated.

There are two Type of Technical Losses.

(a) Permanent / Fixed Technical losses:

Fixed losses do not vary according to current. These losses take the form of heat and noise and occur as long as a transformer is energized.

Between 1/4 and 1/3 of technical losses on distribution networks are fixed losses. Fixed losses on a network can be influenced in the ways set out below.

Corona Losses.

Leakage Current Losses.

Dielectric Losses.

Open-circuit Losses.

Losses caused by continuous load of measuring elements

Losses caused by continuous load of control elements.

(b) Variable Technical losses

Variable losses vary with the amount of electricity distributed and are, more precisely, proportional to the square of the current. Consequently, a 1% increase in current leads to an increase in losses of more than 1%.

Between 2/3 and 3/4 of technical (or physical) losses on distribution networks are variable Losses.

By increasing the cross sectional area of lines and cables for a given load, losses will fall. This leads to a direct trade-off between cost of losses and cost of capital expenditure. It has been suggested that optimal average utilization rate on