Geothermal Development at Lihir Island

Abstract

Geothermal power development at Lihir Island in PNG has posed some unusual challenges. These arise from the geothermal resource, the mining environment and from the isolated location. The mining and geothermal infrastructure are both confined within the Luke caldera, a gravity collapse structure on the northeastern coast of Lihir Island. The original purpose of geothermal wells was to assist the mining operations by depressurising and cooling parts of the geothermal resource ahead of mining operations. The potential to harness at least some of the local geothermal energy has always been recognised and when the first deep production wells had been drilled and tested, a feasibility study was made to examine the technical feasibility of small sale geothermal power generation. A 6MW backpressure plant was approved in June 2002 and commissioned in May 2003. As drilling and testing new wells proceeded the geothermal potential was revised and a further 30MW geothermal generation project was approved in June 2003 for commissioning early in 2005.