Structural testing of the third unit of a 700-megawatt coal-fired power plant under development in Preah Sihanouk province has begun, with the new unit expected to go online by the end of the quarter, a government official said yesterday.

The 135-megawatt power-generating unit, which was initially slated to be operational last month, will add to the existing 270-megawatt capacity of the massive Cambodia International Investment Development Group (CIIDG) power station, which first fired up in late 2014.

“The new unit is in its testing phase and will have a commercial operation date soon,” said Tun Lean, undersecretary of state for the Electricity Authority of Cambodia (EAC).

A $383 million joint venture between CIIDG, owned by influential Cambodian People’s Party Senator Lao Meng Khin, and China-based Erdos Hongjun Electric Power Co is developing the power plant under a 33-year build-operate-own concession from the government.

While the company can officially start selling electricity from the new unit once it passes the compliance checks, Lean said the government has not set a definitive date to start purchasing electricity. That would depend on Electricite du Cambodge (EdC), the state-owned energy provider, he said.

Victor Jona, spokesperson for the Ministry of Mines and Energy, said the government hopes to have the third unit linked to the electricity grid within two months.

“After it passes the tests, it will be connected to the national grid,” he said.

The plant’s increased output will help grow domestic energy production, Jona said, adding that the facility will continue to rely on Indonesian coal imports for fuel.

According to the EAC’s most recent annual report, the partially completed CIIDG plant was already the country’s single largest domestic energy provider, producing 1.5 billion kilowatt-hours of electricity in 2015, nearly a third of Kingdom’s total production.

This easily eclipsed any single hydroelectric dam project, as well as the 100-megawatt coal-fired plant owned by Malaysia’s Leader Universal Holdings that sits adjacent to it.