One of World’s Largest Geothermal Units Begins Operations in Indonesia

The first of three 110-MW units at the $1 billion Sarulla geothermal power plant in Indonesia’s North Sumatra province commenced commercial operation this March. When the next two units come online as anticipated by 2018, the plant will be one of the largest geothermal power plants in the world.

The unique project operated by Sarulla Operations combines flash and binary technologies to increase efficiency and features a 100% reinjection of the exploited geothermal fluid (Figure 6).

6. Graining ground. When completed in 2018, the $1 billion Sarulla geothermal power plant in Indonesia’s North Sumatra province will have a capacity of 330 MW. The plant comprises a backpressure steam turbine and Ormat Energy Converters, which are heated by the low-pressure steam exiting the steam turbine. The technology allows nearly 100% reinjection of the geothermal fluid back into the reservoir. Courtesy: Toshiba

Construction on the project began in 2014, essentially seeking to develop two geothermal resources, Namora-I-Langit and Silangkitang. Toshiba Corp. supplied the geothermal steam turbines and generators for the flash systems, while Ormat Technologies provided the conceptual design of the geothermal combined cycle unit power plant. Ormat also supplied its Ormat Energy Converters, which serve as the condensing units for the steam turbines and utilize the separated brine for maximum resource exploitation and maximum power output, Ormat said in a statement.

Hyundai Engineering and Construction Co. was the engineering, procurement, and construction contractor. Power generated from the first unit will be sold to Perusahaan Listrik Negara, Indonesia’s government-owned electricity company, over a period of 30 years.

The project has a number of high-profile owners, including the Itochu Corp. (25%), Kyushu Electric Power Co. (25%), PT Medco Power Indonesia (19%), and INPEX Corp. (18%). Ormat International holds the remaining shares in the operation company. It also has a long list of financial backers: The Japan Bank for International Cooperation loaned $492 million, and other financiers included the Asian Development Bank, Bank of Tokyo-Mitsubishi UFJ, ING Bank, Societe Generale, Sumitomo Mitsui Banking Corporation, Mizuho Bank, and National Australia Bank.

Sonal Patel is a POWER associate editor