PAPUA New Guinea will account for 75.8 per cent of the total primary energy demand in the Pacific by 2035.
And according to the Asian Development Bank, there was a need for PNG to maintain its focus on hydro-generation for electricity rather than increasing fossil fuel electricity generation.
In its Energy Outlook for Asia and the Pacific report, ADB said PNG's investment environment needed to be improved through regulatory and administrative processes that enhanced accountability and transparency of the investment process.
"ADB is a major financier of renewable energy and energy efficiency improvements for the power sector in the Pacific, with an existing public sector financing portfolio in renewable energy and energy efficiency of $US187.5million ($F346m) and a projected portfolio from 2013-2015 of $US270m ($F498m)," the report said.
"This includes hydro development in Solomon Islands, solar development in Cook Islands, Samoa, and Tonga, and wind development in Micronesia."
Meanwhile, the bank said while Fiji was endowed with hydro resources, it was still partially reliant on expensive imported fossil fuels.