1 of 10 Environmental Technology and Management Conference 2006 September 7-8, 2006 Bandung, West Java, Indonesia Marine Current Potential Energy for Environmental Friendly Electricity Generation in Bali, Lombok and Makassar Straits Rima Rachmayani a* ; Genia Atma Nagara a ; Totok Suprijo a ; and Nining Sari Ningsih a a Oceanography Study Program, Institut Teknologi Bandung, Bandung, Indonesia Corresponding Author * : rhyme@geoph.itb.ac.id ABSTRACT Application of three-dimensional hydrodynamics model of Princeton University, Princeton., (1977), POM, accommodating diagnostic condition, tides and wind as generating forces has been ulitized to simulate marine current in Bali, Lombok, and Makassar Straits. It has typically been to identify appropriate sites for marine energy extraction and quantify the potential energy available for extraction. In this study, potential current energy in the three straits was estimated for environmental friendly electricity generation by applying Fraenkel equation. Two weeks simulation of horizontally and vertically marine current show that marine current in Bali, Makassar, and Lombok Straits are very strong. Current pattern in Makassar, Bali and Lombok straits show current movement as the same of tide pattern which in return movement. From the results, indicate that the tide current represent the dominant current component have kinetic energy potency for the electric generation. It also indicate that Lombok Strait have current kinetic energy potency larger compared to other straits. Keywords: hydrodynamics, straits, tides, marine current, potential, environmental friendly, energy 1.0 INTRODUCTION In fact the ocean represent an energy resource which is theoritically far larger than the entire human race could possibly use, although most of this huge resource is inaccessible in practice [7]. It also could be exploited to contribute in a sustainable manner to meeting the increasing global energy demand. Recently, Indonesia has been experiencing explosive economic growth and increasing demands for energy. Indonesia is well-endowed with all forms of renewable energy. One of potential ocean renewable energy sources is marine current, caused by tidal effects and thermal and salinity differences [9]. Due to the complex characteristics of marine current and their energy extraction hydrodynamics, the development of technologies to harness this resource requires a great deal of research. Many fundamentals of curent energy are now well understood, but there is no consensus yet over the best technology to exploit the resource. The technology has the potential to play a growing role in the coming decades [2]. Marine current as kinetic energy, can be converted into electric energy or other energy. Energy from marine currents offers the promise of regular and predictable electrical generation at higher power densities than other renewables. The key is a site with a forceful flow of ocean waters. Strong flows tend to occur within straits, between islands, and at entrances to large bays and harbors. In Indonesia, promising locations are indicate from observation for marine current extraction are Bali, Makassar, and Lombok Straits. Hence, the three straits have high potential current energy [4]. Though the straits are potential for potential current energy exploitation, estimation of potential current energy in the straits has not been completely done, through this study, potential current energy in the three straits was estimated for environmental friendly electricity generation. Because of scarce current measurement data and with the development of both computer and numerical methods by means of mathematical equations for solutions of time-dependent flows, numerical simulation has become an