National Electricity Day, or Hari Listrik Nasional, is observed in Indonesia every October 27 to commemorate the nationalization of the country's electric and gas companies during the Indonesian National Revolution. The celebration highlights the significance of the electric power sector for the nation's economy and the well-being of its population. The origins of electricity in Indonesia date back to the late 19th century when Dutch plantation owners installed electrical generators. Following World War II, young Indonesian revolutionaries seized control of the electricity sector, leading to the establishment of the Bureau of Electricity and Gas by President Sukarno in 1945. This organization later evolved into the State Electricity Company (Perusahaan Listrik Negara, PLN), which until 2002 held a monopoly on electricity distribution. Despite efforts to deregulate the sector, legal challenges have maintained PLN's monopolistic status. The day serves as a professional holiday for PLN employees and emphasizes the progress made in electricity access, with 98.9% of the population connected as of 2019.