Benefits of optimal size conductor in transmission system

Millions of kilowatt-hours of energy is continuously transferred from generation end to load end through transmission lines. Lower transmission loss in a power system increases the transmission efficiency and reduces the unit cost of electricity. This loss is generally reduced either by increasing the transmission voltage and or decreasing the resistance of the transmission conductor. The decrease of resistance usually increases the volume of the material incurring a higher cost. This paper proposes a cost model with a view to evaluate the optimal conductor size for a given voltage level in the transmission sector of a power system. The optimization model is applied to Bangladesh Power system (BPS) to evaluate the optimal conductor size for each of its existing lines. Comparing the losses the annual benefits of the use of optimal conductor is also evaluated. The evaluated results show that the selection of the conductor size for the transmission system requires careful attention.