Connections

May 20, 2021 Renewables
Renewables
Harvesting a New Crop in Iowa: Expanding Newport Substation Allows CIPCO to Interconnect with New Solar Farm in Wapello

Unleashing the Power to Interconnect, Part 2

This is the second in a series of blogposts about how Ulteig creates connections between clean energy developers and utilities. In today’s fast-paced, clean energy world, relying on an engineering firm that has gained the trust of both utilities and clean energy developers is critical to success. In upcoming blogposts, watch for stories about how Ulteig makes a difference for its clients. Read more project success stories in Ulteig’s 2020 Year-in-Review.

When many envision solar power installations, their thoughts naturally turn to places where it’s hot and constantly sunny, such as desert areas in the southwest United States. But as solar power matures and becomes more effective in harvesting the power of the sun, we’re seeing utility-scale solar installations sprouting up in many “green” areas. One such place is southeastern Iowa, near the small town of Wapello (pop. 2,067), where the Iowa and Mississippi Rivers converge. Just south of town is the Newport Substation and the new Wapello Solar farm.

Folks tend to forget that farmers, and the small farming towns that dot Iowa and many other Midwestern states that supply America’s farms, need dependable, low-cost energy, just like major manufacturers or high-tech firms do.

“Many of our team members live and work in these rural areas,” said Chad Crabtree, Ulteig’s Market Director for Renewables. “We’ve seen a change in how clean energy is becoming a part of the culture out here. It’s gone from a reluctant acceptance to widely embraced. The future of clean energy in America is here, in places like Wapello, Iowa, where clean energy developers are connecting farm country with America’s power grid.”

It’s here that Ulteig leveraged its 75 years of experience in working with power utilities, its deep knowledge of substation design, and its 20+ years of experience in renewables to create a connection point for the new solar farm to access Iowa’s power grid. Ulteig’s substation team has engineered and designed more than 1,000 high-voltage substations, switching stations and interconnect stations—from 12.5 kV to 500 kV—for investor-owned utilities, cooperatives, municipalities, contractors and developers.

Expanding the Newport Substation

In 2019, Central Iowa Power Cooperative (CIPCO) embarked on a project to reconfigure its Newport Substation and add a line in response to a request for a solar interconnection. The substation, located slightly to the south of Wapello, Iowa, serves as an access point for generation onto CIPCO’s eastern Iowa power grid.

“Based on our experience with substations and interconnects,” said Patrick Deibel, P.E., a technical manager with Ulteig’s substation team, “Ulteig was approached to bid on and would eventually be awarded the design for the reconfiguring of the Newport Substation, connecting it with a new solar project being built on 800 acres adjacent to the substation.”

Working on the Newport Substation was familiar ground for Ulteig’s engineers. Just two years earlier, in 2017, Ulteig assisted CIPCO in the redesign of a 161kV ring bus to expand the Newport Substation to provide more reliability to the overall system. The 161kV ring bus layout provides more flexibility to operate the substation and overall grid as well as allows a future line position to be added into the design. During the start of design and construction in 2017 and 2018, a future line position was not needed, but the new design included provisions for future positions to be integrated into the expansion.

“We’ve partnered with Ulteig for many years,” said Terry Fett, director of engineering and operations for CIPCO. “Their knowledge of our standards and their support through the entire project helped us maintain our schedule, which is always critical during outage scheduling and when connecting to generation facilities.”

Change to Meet Future Demands

CIPCO is a generation and transmission electric cooperative with 13 member systems that serve a population of nearly 300,000 rural and urban residents in 58 counties across Iowa.

In 2019, CIPCO agreed to purchase 100 percent of the energy and capacity output for 25 years from Wapello Solar LLC, a 127.5-megawatt solar facility located on approximately 800 acres in Louisa County, next to the Newport Substation. According to Solar Power World magazine, Wapello Solar is Iowa’s largest solar project. It went commercial on March 8, 2021.

As the engineer of record for the CIPCO interconnect substation, Ulteig provided the electrical physical layout and design for the major equipment, including physical section views, conduit layout, grounding design and lightning protection. The electrical design responsibility also included schematics, wiring diagrams and control panel layouts for the protective relaying and SCADA equipment. The structural component of the project responsibilities included steel fabrication and foundation designs. Ulteig also provided project management services for the design engineering portion of the project.

After working with CIPCO previously, Ulteig’s engineers had the experience of designing not only the Newport Substation but several other substations as well, such as Swan Lake and, most recently, Clear Creek. Ulteig also worked with CIPCO on several transmission line projects. CIPCO currently owns and maintains nearly 2,000 miles of transmission lines, delivering power to over 300-member substation delivery points across CIPCO’s owned and contracted facilities throughout Iowa.

Overcoming Challenges

Working on an existing site can be a challenge, as drawings may need to be conformed to site conditions. In addition, constructability issues can arise during construction that were unknown from field investigation or drawings. During construction, the contractor discovered an underground cable trench that deviated from the substation drawings. The new substation dead-end and associated metering equipment could not be located where designed. Ulteig engineers collaborated with CIPCO engineers and the contractor to overcome this challenging new development and came up with a creative solution, which included relocating the equipment and maintaining proper electrical clearances.

Scheduling became a concern when the Generator Interconnect Agreement (GIA) and funding weren’t in place until December 2019. The in-service date of Nov. 1, 2020 made for a roughly 10-month project schedule to execute engineering, material delivery, construction and commissioning. To meet the Nov. 1 deadline, Ulteig reduced the engineering design process from the typical eight or nine months to just six and a half.

Success: Driving Down Costs

When the site was set up to add an additional line, the only major change required was to relocate an existing line to an open position in the substation, thus terminating the Wapello Solar line in the least expensive and most constructible position. Cost savings were implemented in the line location swap by reusing equipment and relocating it as necessary. 

The goal was to perform the most cost-effective solution with quality engineering in the given timeframe to interconnect Wapello Solar LLC.

But success means more than just schedule adherence. CIPCO expects engineering to have quality, constructible designs, as well as the correct material specified, to execute construction effectively.

“By relying on an experienced team,” said Deibel, “as well as the team’s knowledge of the project based on its previous work at the substation in 2017, we executed a quality design in the required timeframe for the solar farm to connect to the grid.”

Ulteig Creates Connections

The substation upgrades were an important part of providing Wapello Solar with an economical access point to the grid. Ulteig’s work for CIPCO on the Newport Substation represents another example of how Ulteig clearly understands how to work with both utilities and clean energy developers to create the connections they need to deliver reliable clean energy to America’s towns and cities. To learn more about Ulteig’s substation design expertise, click here. Read more project success stories in Ulteig’s 2020 Year-in-Review.

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