Customer challenge

A major petrochemical plant was performing switchgear maintenance on a plant substation during their summer outage. The substation provides power to two critical areas: the main product pump circulation system and the plant fire pump system.

Keeping the product pumps operational was essential. Without these pumps, the product would harden in the pipes, leading to a major outage and shutdown to clean them. Maintaining the prime power feed to the fire pump system was also imperative, as the fire pump system is one of the most critical safety systems in a chemical plant.

United Rentals Power and HVAC solution

Due to site requirements, the length of the electrical outage for connection could not exceed 30 minutes. This made a single medium voltage tie-in the only logistically possible solution.

Leveraging its access to a broad range of components and in-house engineering expertise, United Rentals developed a custom temporary substation package that satisfied the continuous prime power load requirements while also providing the redundancy that was necessary due to the critical nature of the substation. The package included 3 MW of paralleled temporary power as well as a transformer, amp secondary disconnect, amp LV disconnect and cabling. United Rentals also provided onsite technical support.

The system was assembled and tested prior to mobilization to ensure it would provide a 30-minute changeover once on site.

Impact

The temporary substation ran 24/7 for 10 days with zero maintenance issues, which allowed the product to continue circulating during the outage. The system design saved the plant time and money because once it was placed on site, the customer’s electrical team needed only to make the 3 MV cable connections to their bus.