Ocean Engineering

Abstrak: Jack up drilling rigs adalah salah satu MODU (Mobile Operation Drilling Unit) yang banyak digunakan untuk eksplorasi minyak dan gas pada instalasi jacket di perairan dangkal yang tidak memiliki kelengkapan fasilitas drilling. Faktor keamanan merupakan salah satu hal penting yang perlu dipertimbangan dalam perancangan struktur sebagai upaya untuk mengantisipasi terjadinya kegagalan selama umur layannya. Penelitian ini bertujuan untuk menghitung besarnya nilai kehandalan () struktur jack up dengan pendekatan LRFD , dimana analisanya dibatasi pada analisa statis dimana struktur akan menerima beban gravitasi dan beban lingkungan yang berupa beban gelombang. Dengan mengasumsikan bahwa jack up dalam kondisi elevated mode memiliki kekakuan yang sama dengan jacket maka untuk analisa kekuatannya akan didasarkan pada aturan API RP2A LRFD. Metode simulasi Monte Carlo dipilih sebagai metode untuk menentukan besarnya nilai kehandalan. Dari hasil analisa perhitungan dan simulasi didapatkan nilai Unity Check(UC) yang hanya dipengaruhi oleh kapasitas dan beban gravitasinya saja. Diperoleh besarnya nilai kehandalan() komponen jack up yaitu sebesar 21,4. Hal ini menunjukkan bahwa jack up yang beroperasi selat Makassar memiliki kapasitas yang sangat besar dan sangat aman untuk bertahan di perairan tersebut.

Tidal current energy is a renewable energy that fluctuates following tidal patterns. This condition causes tidal current energy to be unstable and cannot be used commercially to meet national energy needs. Energy storage is one solution to keep the tidal energy of the sea water constant and usable. In this research, it is expected that the results will be obtained in the form of specifications for the optimal energy storage reservoir and adapted to the environmental conditions of the study area. The expected reservoir optimization condition is a reservoir that has specifications that are efficient and economical in terms of construction costs. The research started by modeling the tidal current velocity using MuHydro3D software. The research study area is the Larantuka Strait area, East Flores Regency, NTT Province. After that, the tidal current energy is calculated which is planned as energy for the sea water pump. Seawater pumps drain seawater to reservoirs at a certain elevation. On the other hand, the planned electricity demand is determined based on the electricity demand in Larantuka. From the electricity demand by using the potential energy equation, the discharge requirement is obtained. The difference between seawater pump discharge and demand discharge within one year of experimentation results in reservoir volume requirements. In the process there is an application of head losses, the calculation of head losses only includes major criteria. The optimization process for energy storage reservoirs includes optimization of reservoir specifications and construction costs. The results of this study are reservoir specifications for optimal conditions with the calculation of optimal construction costs for the conditions of the study area.

The global initiative for decarbonisation keeps growing at a different rate for each country. The global decarbonisation rate, which presents the carbon intensity reduction or energy-related CO2 emissions per dollar GDP, reached 2.5% in 2020. Indonesia recorded contributing as the second-highest rate of emissions reduction in the global decarbonisation rate during 2019-2020 with a total of 10.6% less carbon intensity. Solid infrastructure asset management shall significantly improve to support the further decarbonisation movement. As one of the cleanest carbon energy, LNG could be the fastest solution to keeping the initiative. Unfortunately, it has a drawback: methane produces higher Green House gases (GHG) than CO2. Furthermore, LNG acts as a transition fuel while the global industry prepares for renewable energy resources. The authors propose Adaptive Port Planning (APP) and Engineering Asset Management (EAM) framework for managing the existing LNG infrastructure terminal assets ...

Global trade for regasification LNG has reached 850.1 MTPA by February 2021 because of the enforcement of clean energy applications. The alternative of renewable energy such as hydropower, solar, and wind has developed globally, but they have not been implemented effectively in Indonesia. LNG became an alternative to clean energy because of its low carbon emissions. An estimated 26% of the 35,000 MW of Indonesia’s electricity supply project comes from natural gas-powered power plants. The scope of this study is to investigate the implementation of adaptive planning for LNG regasification facilities. The authors interview the LNG experts in Indonesia to assess uncertainties, vulnerabilities, and opportunities in its business process to identify the enabling factors for implementing the adaptive method in LNG terminal master planning. This research aims to provide an adaptive strategy for LNG Regasification Terminal to satisfy resilient and sustainable infrastructure concepts. The aut...

Desa Bulak merupakan daerah yang berada di Kota Surabaya, dengan penduduk mayoritas bekerja sebagai nelayan. Permasalahan yang terjadi pada nelayan mengenai sulitnya bongkar muat hasil tangkapan ketika selesai mencari ikan. Hal ini dikarenakan lama waktu yang dibutuhkan untuk mencari ikan saat air pasang tidak bisa diprediksi dan nelayan tidak bisa membawa hasil tangkapan ke darat. Ikan yang akan dibawa perlu dipanggul membuat hasil tangkapan dapat berjatuhan. Penggunaan alat untuk menjaga kualitas ikan menggunakan es batu, tetapi tidak tahan lama dan biaya mahal. Ketika dalam penangkapan ikan membutuhkan waktu lama, maka kualitas ikan menurun yang membuat pendapatan nelayan menurun. Dengan kondisi ini, dilakukan analisi dengan metode HOQ membuat Cool Box Portableuntuk menjaga kualitas tangkapan nelayan dan membantu proses bongkar muat hasil tangkapan. Untuk Cool Box Portable memiliki panjang 1150 mm, lebar 500 mm, dan tinggi 500 mm dengan kapasitas 25 kg. Untuk tinjauan waktu selam...