* Gas deficit to reach 4 bcfd by 2030

* Deficit in west Java to grow by five times by 2030 from 2015

* Gas infrastructure needed to balance supply, demand

SINGAPORE, Oct 25 (Reuters) - Indonesia is expected to become a net importer of liquefied natural gas in 2020 as its population grows, notching up an LNG deficit of 4 billion cubic feet per day (bcfd) by 2030, a senior official from state-owned energy firm Pertamina said on Wednesday.

The increase in population and rising industrial production will likely boost gas demand from the power, industrial and transport sectors, said Irma Surya, general manager of Pertamina’s LNG sales.

Given that 55 percent of Indonesia’s gas demand comes from the island of Java, the province of West Java’s gas deficit will grow by five times by 2030 from 2015, she said at the Singapore International Energy Week.

Gas infrastructure will need to be developed to balance supply and demand between west and east Indonesia, she added.

“The eastern part of Indonesia is in a surplus of gas, while the west and south parts are in deficit, so to cope with the large amount of gas demand in western Indonesia, an adequate gas infrastructure within the region is needed,” Surya said.

This will in turn increase overall gas demand in the country, which will flip to becoming a net importer of LNG for the first time in 2020, she said.

To meet some of the gas demand in Java island, Pertamina plans to build several LNG receiving terminals there, Surya said at the annual conference. (Reporting by Jessica Jaganathan; Editing by Joseph Radford)