Several foreign investors from the US, China, Turkey and Japan have expressed interest in investing in geothermal projects in South Sumatra, says government official.

Eddy Hermanto, an official overseeing economy, finance and development, said the investors were told to complete the requirement for bidding.

"Bidding is part of the Energy and Mineral Resourses Ministry's regulations in offering the project," Eddy said.

One site rich in geothermal resources is located in Rantau Dedap, Segamit subdistrict, Semende Darat Ulu district, Muaraenim regency, which according to Eddy, had an energy reserve of 1,335 megawatts. A eothermal powered plant has been planned to produce between 1,000 and 1,200 megawatts. The construction is expected to commence next year.

Separately, head of South Sumatra Mining and Energy Agency, Robert Heri, said the investor to build the facility was obliged to deposit US$10 million as guarantee. "Those interested in the project are pleased to register and file the required document to the Mining and Energy Agency," Robert said.

South Sumatra, according to Eddy, was the second biggest in the world after the US in terms of geothermal resource. "This is due to the fact that the province holds a caldera that covers the three regions of Muaraenim, Lahat and Pagaralam," he said.

The province is also rich in other natural resources including the country's first biggest coal resource, fifth biggest oil resource and coal bed methane.

Meanwhile, the West Java provincial administration is looking to hire foreign consultants in marketing its geothermal resources.

According to West Java Regional Development Board head Deny Juanda, the services of a world-class consultant should be important in raising trust among investors. "A profitable project must include feasibility studies carried out by a world-class consultant, except if the project is financed in rupiah where an Indonesian consultant can be hired," said Deny.

West Java Governor Ahmad Heryawan visited Shanghai, China, last month and offered three geothermal projects, located at Mount Papandayan, Mount Ciremai and Mount Gede-Pangrango, along with the planned construction of Kertajati International Airport.

It was Heryawan's second visit after offering joint ventures to investors in Guangzhou. The four projects are worth more than Rp 6 trillion (about US$600 million), Rp 3 trillion of which is the estimated value of Kertajati International Airport.