Techno-Environmental Analysis of Hybrid Energy System for Offshore Oil Rig Black Start

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.