Implementing a substation replacement program in an operating refinery (The 10 year plan)

Many refineries are burdened with 50 year and older substations that are at the end-of-life with obsolete equipment. They are susceptible to failure during normal process unit operations. Several substations are in similar condition and require a risk assessment to determine the priority and the year the selected substations are replaced. An interdisciplinary team that understands the risks associated with the substation is required to evaluate the consequences of a power loss to the process unit, such as environmental impacts, loss of production and safety integrity of the equipment. The team will also advise during the design of a new substation that is maintainable and maximizes reliability. This paper discusses the implementation of a 10 year plan to replace aging process unit substations in a large Southern California refinery. The paper emphasizes key aspects of planning and scheduling construction work and outages in operating refinery units and discusses technical challenges and lessons learned. It also presents an overview of the general cost categories and highlights least considered items that impact the total cost of the program. The paper demonstrates how an assembled team that is knowledgeable with process unit operating, reliability maintenance, and process unit optimizing can design a substation that is maintainable, reliable, and through the life of the substation maximize profits through on-line availability of electrical power for the process unit.