TEMPO.CO, Jakarta - State power company PLN director of strategic procurement Supangkat Iwan Santoso admits that the weakening of the national economy will make electricity demand decline. As a result, electricity reserves will increase.

A study by the Institute for Energy Economics and Finance Analysis (IEEFA) predicts that the Java-Bali electricity system will have reserves of 40% starting in starting 2019. This reserve, IEEFA claims, will burden PLN's finances, forcing the company to spend US$16.2 billion capacity payment to private power producers until 2026.

Read: PLN Mulls Using Renewable Energy Sources for Power Plants

However, Iwan argues that power reserves are necessary to maintain the continuity of national electricity supply. He says that the power backup is useful to replace electricity that is lost in the transmission process. Reserves are also useful to act as backup when PLN's biggest power plants run into trouble.

Based on PLN's Electricity Supply Business Plan (RUPTL) 2017-2026, PLN estimates that electricity supply will reach 30 percent.

The electricity system outside Java-Bali in 2019 will have a backup of more than 30 percent. The highest reserves are estimated to be in Nias with 94 percent, followed by West Kalimantan with 73 percent.

"The unused electricity is included in our plan," said Iwan, yesterday, October 3.

ROBBY IRFANY