16.10.2017: In September 2017, the first geothermal low-temperature demonstration power plant in Indonesia has been successfully commissioned at the geothermal field in Lahendong close to the village Pangolombian, North Sulawesi. The demonstration plant is now in test-operation.

The concept of the demonstration power plant has been developed by the Helmholtz Centre Potsdam – GFZ German Research Centre for Geosciences in collaboration with the Indonesian project partners BPPT (Agency for the Assessment and Application of Technology) and PGE (Pertamina Geothermal Energy). The project was funded by the German Ministry of Education and Research (BMBF). The aim of this collaboration is to demonstrate reliable and efficient low-temperature power generation at a geothermal site in Indonesia and to create the basis for a broader application in Indonesia.

The demonstration plant is designed to cool down part of the unused geothermal brine from 170 °C to 140 °C and thus generate electricity. During the test-operation, the temperature of the geothermal fluid is 145 °C, which results in an electric power output of approx. 300 kW. In normal operation, an electrical capacity of up to 500 kW shall be reached. Assuming the average electric power consumption in Germany, this is enough to supply electricity for 1,200 households.

The geothermal demonstration plant is based on an Organic Rankine Cycle (ORC) connected by closed water intermediate circuits (a hot water and a cold water intermediate circuit) to the geothermal heat source and the environment as heat sink.

Building on the experience of the development and operating phase of the demonstration power plant, the implementation of low-temperature power plant technology for Indonesia can be decisively advanced. With the establishment of this technology, it is possible to extend the electrical capacity of existing geothermal sites and, above all, to provide an option for the decentralized energy supply in Indonesia.

The research and demonstration operation of the low-temperature power plant is to be continued under the leadership of the GFZ until the middle of 2018. The demonstration plant will then be handed over to an Indonesian partner organization.