ABSTRACT

YAPPA BARU. The Role of Power System Operator in a Competitive Electricity Market (supervised by Muhammad Arief and Nadjamuddin Harun).

The aim of this study is to identify the role of a power system operator in a competitive, transparent and efficient electricity market (as required by Article UU No. 20/2002) that is expected to take the place of the present monopolistic and centralistic, outdated – ceased to develop - electricity market. The cost of power generation, consumer’s demand and the transmission congestion are among important factors to determine the related Lagrange equation. The energy cost and the injected power at every bus are optimized using the gradient method based on Karush-Khun-Tucker condition. The generator’s input-output equation is derived through a least-square method using potential customer’s spending budget for electricity (data from PLN, the existing sole-operator) and the DC power flow equation derived using Gauss-Seidel method.

The study is conducted in the region of South Sulawesi and South-East Sulawesi with 5 (five) power buses taken as samples, i.e.: Bakaru, Sengkang and Suppa (generator buses), Soppeng and Tello (load buses). Energy cost and injected power are optimized according to operational realization of the five buses at 11:00 a.m., April 24, 2004. The results show that the energy cost per MWh and the injected power at Bakaru, Sengkang, Suppa, Soppeng and Tello are Rp 112.304,06 over 62,5 MW, Rp 615.234,05 over 50,7 MW, Rp 231.037,75 over 45,5 MW, Rp 344.570, - over 23,4 MW and Rp 412.430, - over 135,43 MW respectively. This generates revenue as much as Rp 15.183.066,28 in one-hour operation for the system operator.

At the peak load – when the customer’s demand is a way above average – the optimization of energy cost over injected power at the three generator buses are beyond their generating capacities. It is expected that small capacity generators will supply additional power, which creates a new competition. It is concluded that the system operator has a very important role in creating an efficient, transparent and competitive electricity market.