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The use of Diesel Generators (DGs) and gas turbines to power oil rigs is characterized by pollution due to the emission of harmful gases like carbon dioxide, very high noise levels, high maintenance costs, and the inability to start the platform if the DG fails. Offshore wind energy generation system provides a viable alternative means of powering the oil rig and can also be integrated to operate in parallel with gas turbines. However, offshore wind energy might fail if not properly designed due to the high variability of wind resources. Hence, the objective of this work is to design offshore Wind Turbine Generator (WTG) energy generation system, DG, and hybrid DG-WTG for the black start of an offshore oil rig. The designed energy systems are simulated using HOMER Pro. Furthermore, the performance of the simulated systems was evaluated using the electrical production, unmet load, and emission profile as the performance metrics. The results of the hybrid DG-WTG powered black start revealed that 150kW DG generated 322,071kWh/yr representing 6.77% of the total generation and 1.5MW WTG generated 4,434,632kWh/yr representing 93.2% of the total generation. The comparison of the emissions from DG and DG-WTG revealed that 294,058kg/yr, 1,945kg/yr, 80.9kg/yr, 9.02kg/yr, 720kg/yr, and 688kg/yr of CO2, CO, UH, PM, SO2, and NO, respectively, were released into the atmosphere by DG-WTG which is very low compared to 969,129kg/yr, 6,109kg/yr, 267kg/yr, 37kg/yr, 2373kg/yr, and 5739kg/yr of CO2, CO, UH, PM, SO2, and NO, respectively, released into the atmosphere by DG. The sensitivity analysis revealed that while the electrical production of 100kW and 50kW DGs decreased with an increase in WTG height, the electrical production of 1.5MW WTG increased with an increase in WTG height. It was further revealed that the higher the WTG height the smaller the quantity of the emission released into the atmosphere. [ABSTRACT FROM AUTHOR]

Summary: The diesel generators are usually used for supplying the electrical demand of the semi‐submersible oil drilling rigs. The specific fuel consumption (SFC) of each diesel engine changes nonlinearly with respect to its power product. Hence, this paper presents an economic fuel dispatch model for diesel engines powered oil rig platforms using the cubic spline interpolation curve fitting of the SFC‐power non‐linear dependence. Moreover, the total fuel consumption of the diesel generators significantly reduces by shifting a partial part of the electricity demand of the offshore drilling rigs from on‐peak time intervals to off‐peak periods. In addition, battery energy storage contributes to the load curve smoothing strategy. A mixed‐integer non‐linear programming problem is developed under generalized algebraic mathematical modeling system to find the optimum fuel consumption and power generation schedules of the diesel producers, the value of demand increase/decrease, and the charge/discharge pattern of the battery at each operating time interval. A benchmark oil rig with eight diesel engines and four tidal turbines is considered to validate the proposed methodology. Four cases are studied without and with application of battery and load shifting program. It is found that implementation of peak‐clipping and valley filling to energy demand pattern and battery integration with tidal‐diesel driven oil rigs cause a significant fuel saving. In the presence of battery, 70 g fuel saving is achieved over a 24‐hours study horizon. Moreover, the implementation of time‐based load shifting program with the capability of 30% load decreasing (at peak hours) and increasing (at off‐peak periods) makes it possible to save 282 g diesel fuel according to the base electrical demand profile. Finally, simultaneous integration of battery and demand‐side management programs (with maximum 10% load flexibility) causes 216 g fuel saving in sample operation day. [ABSTRACT FROM AUTHOR]

The oil rigs that will be installed in the Lebanese offshore are floating rigs. This type can be affected by environmental risks such as extreme wind speed and wave height. We study these risks in Beddawi region in the northern Lebanon during the winter season by applying the extreme value theory to real data. We estimate at a first stage the return levels associated to return periods of 50, 100, and 500 years for each risk separately using the classical univariate theory. At a second stage, we use the logistic parametric model and the bivariate copula functions in multivariate extreme value theory to estimate the dependence between extreme wind speed and wave height as well as joint exceedance probabilities and joint return levels to take into consideration the risk of these two environmental factors simultaneously. [ABSTRACT FROM AUTHOR]

This paper describes the operational procedures and the conditions that exist and prevail in the Search and Rescue (SAR) at sea for endangered offshore platforms (oil rigs) in Greece. More specifically, the authors collected and elaborated all the necessary information of a thorough risk governance gap analysis by means of selective scenarios all along the SAR process, while paying special attention to the respective risk governance issues. Particular information is provided for the SAR in the Greek Search and Rescue Region (SRR), for the purpose of identifying vulnerable conditions such as responsibility gaps and duplication or overlapping of duties among the different partners and stakeholders that may result in confusion and lead to operational failures. The authors approach the international and national legal framework concerning the SAR issue, the identification of the potential for SAR operations in the Greek region, namely, the Search and Rescue Units (SRUs) in Athens FIR and the public services and governmental organizations, which are likely to be involved. An analysis of the coordination process among the above mentioned stakeholders is done along with the determination of various peculiarities/uncertainties that may arise during the management of communication. The paper concludes with a proposal for action plans in various SAR scenarios and suggestions on possible locations for the On Scene Coordinator (OSC) basis. A list of possible problems and shortcomings is presented and associated with a corresponding list of solutions. [ABSTRACT FROM AUTHOR]

The May 2014 entry of a Chinese deep-water oil rig into Vietnamese waters deeply shocked Vietnam. This yearend article chronicles the impact of the controversial action on (1) power struggles among elite politicians, (2) alterations in foreign policy orientation, and (3) popular opinion regarding economic reforms and emerging inequality. [ABSTRACT FROM AUTHOR]

There are 1.3 million sailors in the world and 6 000 of them die every year. On average there are 5 marine accidents at sea worldwide every day. This paper aims to describe serious tanker and oil rig accidents within the last century and at the beginning of the present century. Many human lives were lost in those accidents, flora and fauna have been irrevocably damaged and efforts are still being made to recover from their economic consequences. [ABSTRACT FROM AUTHOR]