The first geothermal low-temperature demonstration power plant in Indonesia has been commissioned and is now undergoing trials.

The aim is to demonstrate reliable and efficient low-temperature power generation at a geothermal site and create the basis for a broader application of this technology.

The plant is designed to cool part of the geothermal brine from 170°C to 140°C to generate electricity.

During the test operation, the temperature of the geothermal fluid is 145°C, which results in a power output of around 300kW. In normal operation, an output of 500kW can be reached — enough to power 1,200 households.

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

The concept has been developed by the GFZ German Research Centre for Geosciences in collaboration with Indonesian partners, and the project was funded by the German Ministry of Education and Research.

It will continue under the leadership of GFZ until the middle of 2018. The demonstration plant will then be handed over to an Indonesian partner.