Renewable Energy Offshore: The Front-End Engineering Design of a Solar-Powered Unmanned Wellhead Platform

Abstract This paper details the engineering and design process during the Front-End Engineering Design (FEED) stage for a solar-powered, unmanned Wellhead Platform (WHP). The objective is to demonstrate the feasibility and benefits of combining a standalone photovoltaic (PV) array with battery storage as the primary source of power supply during unmanned operation, supported by a battery charger as ancillary backup while employing a Diesel Engine Generator (DEG) as power generation during manned operations. The FEED study involved sizing a power generation system, including Ex-rated solar PV with battery bank, battery charger and a Diesel Engine Generator (DEG). The process included identifying preliminary load consumption for all platform systems, such as instrumentation, lighting, and utilities pumps. The design process of solar PV system utilized historical solar radiation data spanning several years to support the energy storage demands, specifically the number of autonomy days. Detailed layout generation for the solar panels and battery bank was performed, and a monitoring system was specified for both local and remote performance tracking. The design accounted for both normal unmanned operations and operator-visit scenarios. The FEED result successfully integrated a solar PV system as the main power source for the unmanned WHP. Preliminary load analysis determined that solar power could supply all essential loads, including integrated control and safety systems and hydraulic pumps, with the DEG serving as a backup for specific maintenance activities and emergencies. The design incorporates a 24 VDC distribution system for solar-powered loads and a 400/230 VAC system for the DEG. This approach significantly reduces the platform's reliance on fossil fuels, leading to a notable reduction in emissions and operational costs during normal operation. This paper also presents a case study focused on the successful FEED of a solar-powered unmanned wellhead platform (WHP) located in the Natuna Sea, Indonesia. It offers a practical, step-by-step guide for engineers on how to integrate and size a standalone renewable energy system for unmanned offshore facilities, addressing specific challenges like load management, system redundancy, backup and remote monitoring in a real-world application.