A post-Sandy hardening program illustrates the role innovative design and community engagement play in the future of power delivery
There’s been a perfect storm in electric power delivery in the past decade as suppliers across the globe cope with upgrading aging infrastructure, improving reliability of the system, and strengthening the grid against an increase in extreme weather events. Nowhere is this more relevant than in the US Tri-State (New York, New Jersey, and Connecticut) region, where nearly 1.3 million people live in the 100-year floodplain.
Sparked by a series of significant events—including the 2003 blackout that caused 50 million to lose power across the US Northeast and Southeastern Canada, and Superstorm Sandy in 2012, where devastating flooding and downed trees left millions without power in New Jersey alone—utility providers like PSE&G are updating their portfolio of substations and lines to improve network reliability and resiliency.
The Stantec Power team has been working with PSE&G for almost six years on this program in New Jersey to improve power service and capacity to communities like Hoboken and Jersey City. Our role is focused on project design, engineering of substations, and procurement of long lead equipment. This includes replacing older substations, eliminating those that are no longer necessary, creating redundancies to reduce disruptions, and protecting this infrastructure from future storms and flooding.
Our client’s goal for the communities they serve? Creating a more resilient and reliable system. This means a system where the lights don’t go out as often. Where, if a major storm hits, it won’t affect customers’ homes, their emergency services, or the power needed to support business and local infrastructure.
Elevated substations are designed with advanced materials to better withstand storm impacts.
Enhanced style and function for resiliency
To accommodate PSE&G’s goal, our team set out to enhance the style and function of the substations, many of which were nearly 100 years old.
As part of the modernization program, a segment of the new substations in the portfolio are being designed with more circuits and, as a result, a more reliable supply network. In the past, substations would typically have one supply. To mitigate possible outages, utilities would place two substations on a site as a back-up. If a circuit from one failed, the system could pick up customers from the second substation.
_q_tweetable:This means a system where … if a major storm hits, it won't affect customers’ homes, their emergency services, or the power needed to support business and local infrastructure._q_Today, these new substations can support the power of two older substations with as many as four supplies. So, if one of the supply lines drops, this modern station will automatically transfer to the other three lines until the utility is able to determine the issue. The supply will segment itself almost instantly so that customers aren’t without power and, if they are, it’s only for a few seconds rather than hours.
These functional modernizations have allowed for an automated system that’s operated remotely, as opposed to the manual throw-over systems of yesteryear where an outage would require a person to physically work on the substation to get that portion back online.
In addition to a modernized power delivery system with automated redundancy, the new substations are also designed to better withstand storm impacts. This means that substations are elevated well above the floodplain for critical equipment, as identified by the Federal Emergency Management Agency (FEMA), and are designed with advanced materials that can endure extreme winds.
For example, in Hoboken we’ve designed the substations with all critical equipment installed 10 feet above ground to meet FEMA’s flood plain requirements and the client’s desire for a proactive approach to resiliency. This brings an increased level of project complexity because equipment that has typically been installed on a slab on the ground will now be built on steel platforms 10 feet in the air.
From a design perspective, this required several adjustments from the norm. A specialized design was needed for a rigid platform to support the heavy substation equipment and withstand wind factors of up to 130 miles per hour. There also was special attention paid to placement of the equipment, which would be typically buried underground, to be supported from these platforms and offer safe access for utility workers.
Our solution involved designing a substation with cables installed in conduits that are mounted underneath the platform. To run the conduit successfully and make sure there’s no interference with the structure, our team developed 3D models that allow us to fly through the design to identify and address any potential obstructions. This model was also helpful to the contractor in understanding exactly what paths had been identified for the conduits and the material required, as well as for the client to have a hands-on understanding of this specialized equipment in the early project stages.
A newly elevated substation features conduits designed to avoid interference with the raised structure.
Working with the community in mind
Performing work in any dense urban community presents unique challenges. In addition to being prepared for issues like construction noise and having adequate space for project work, our team was especially sensitive to making sure these upgrades were implemented without interrupting service.
Since most of our work involved modernizing and upgrading capacity of existing substations, it was essential to make sure the community wasn’t left in the dark. To address this challenge, we created contingencies—basically compact temporary stations—located adjacent to the existing substation being upgraded. The energy load was transferred to the temporary substation during the upgrade work and then moved back to the new station once work was complete.
Construction-noise management was also a primary focus as we worked to create as little disruption as possible to residents. In many cases, our designs required that support piles be installed up to 100 feet in the ground, creating a great deal of noise in this tight environment. Being conscious of noise disruption, we started testing helical piles as an alternative. The helical pile is basically a long shaft that’s drilled—rather than hammered—into the ground. Sections of shaft are added until the pile reaches appropriate soil or bedrock. By pairing these helical piles with pipe piles, we’re able to accomplish a solid support system with less disruption to residents. This new system is being tested on one substation currently in the works, with plans to evaluate and apply the system to similar projects.
Construction in a dense neighborhood like Hoboken, New Jersey, requires additional planning and strategic staging to mitigate disruptions to residents.
Designed to hide in plain sight
The visibility of the raised substations presented another unique challenge as this type of equipment is typically meant to hide in plain sight. In urban settings, you’ll often find a substation concealed behind a false building façade or fencing. So, how do you design a 10-foot high structure to complement the local landscape?
In Hoboken, we blended style with function to create a structure that also served as a piece of art. Located in the center of the city adjacent to a park, the client and local community leaders knew this substation upgrade presented an opportunity to enhance the streetscape. To accomplish this, we created a design that resembles a Chinese lantern with a special polycarbonate material along the top that allows light to shine through for a subtle and eye-catching glow. The substation also is enclosed with design-driven materials, as opposed to a typical fence, using a unique concrete fiber material that gives an added layer of dimension when the lantern’s light shines through.
The result is an interesting community centerpiece within a newly enhanced electric grid with capabilities for improved power delivery no matter what Mother Nature may bring.
About the authors
Daniel Mahoney is a senior project manager in our Power group based in Auburn, New Hampshire. He has more than 30 years of experience focused on transmission and distribution, major substation, and underground line projects.
Mihai Oros is a senior project manager in our Power group based in Wyomissing, Pennsylvania. Mihai is an expert in engineering design, structural design, and transmission line design.