Abstract: “because Java-Bali system is weak. The power system stability needs to be increasing the 500 kV transmission lines. The construction of the south transmission line, planned since 1996, has been hampered by land acquisition problems. Locals in Depok in West Java and in Klaten and Bantul, Central Java, have refused to make way for the power line. A simulation by using Etap Power Station shows phenomena occurred during the blackout on August 18th 2005 the northern transmission line capacity extremely high (EHV) 500 KV transmission line Saguling-Cibinong (middle transmission line) is the only interconnected transmission line to invert electrical power from power station in East Java to West Java and Jakarta. The interconnection network along the Saguling-Cibinong transmission line cannot handle additional load since it almost reach its capacity limit. Moreover it is not flexible enough to supply power to Jakarta. By adding the north transmission line Muaratawar-Cawang and Muaratawar-Cibinon”

Keywords: blackout, security, EHV 500 KV, transmission line.