Bridging Relocation challenges

By Brian J. Flier, Kansas City Power & Light

Utilities deal with road and highway relocations everyday, but what does a utility do when it must design a 100-foot tall distribution pole to accommodate a relocation? That is the challenge the Missouri Department of Transportation (MODOT) presented when it asked Kansas City Power & Light (KCP&L) to relocate several distribution lines that traversed and paralleled Interstate 29/35.

The MODOT project included construction of a new cable-stayed, six-lane bridge alongside the existing bridge. Several distribution lines had to be moved to allow for construction of the new bridge and its approaches. MDOT used a construction approach known as build-as-you-go, which ultimately meant that deck information could not be finalized until the build was complete. When the calculations were finished, the contractor informed KCP&L that several of the relocated poles needed to be more than 100 feet tall.

Workers set a pole during the relocation of distribution lines.

KCP&L had limited experience designing poles larger than 60 feet; so it needed a manufacturer willing to team up on the new poles’ design. Once the contractor identified the affected poles, KCP&L solicited interest from several steel manufacturers. The extremely short lead-time made it necessary to consider other options. Although KCP&L had limited experience with laminated structures, it selected Laminated Wood Systems (LWS) to design and supply the poles.

The old structures were 69kV lattice tower structures retrofitted with 15 kV equipment. KCP&L decided to keep the original circuit path and install taller poles. This path included some large angle transitions and included spanning 12 sets of railroad tracks. KCP&L provided LWS with the entering and exiting angles, tension of the conductors and the soil classification in which they would install the poles. The team selected vertical construction to make the transitions easier and allow KCP&L to double dead-end at the structures and jumper around the poles. Building the line vertically presented several challenges:

  • How much sag should the conductors have, and how would that affect the design?
  • What was the appropriate clearance to the other structures, buildings, cars etc?
  • How far apart should they install the conductors to prevent galloping? 

To overcome these issues, the three 120-foot vertical poles were pre-cambered, and each consisted of two poles built with a separation between them to allow for mounting the insulator hardware. The cross-arm design of the other two poles would facilitate the transitions from the smaller poles that led to and away from the new structures.

A drill rig makes holes for relocated power poles during construction of the Christopher “Kit” Bond Bridge in Kansas City.

It was necessary to use a 7 to 8 foot diameter auger to drill the holes so the laminated poles could be embedded 15 to 20 feet below ground. The railroad required corrugated steel caisson tubes in the upper half of the pole holes for the three structures installed on its property. Once the poles were set, the holes where filled with 4,000-pound test concrete and supported by several boom trucks until the concrete could cure. When the poles were ready, KCP&L strung new conductor and removed the old structures and lines.

Pole casings wait to be installed during the construction of the Christopher “Kit” Bond Bridge in Kansas City.

The Christopher “Kit” Bond Bridge, now a new Kansas City icon, would not have been possible without the dedication and innovation of KCP&L and LWS. By working closely with its customer, MDOT, and its supplier, LWS, Kansas City Power & Light timely relocated its poles, which helped MODOT complete the new bridge ahead of schedule. 

Another shot of drilling work during construction.


FPL delivered 99.98 percent reliability in 2010 

In a filing with the Florida Public Service Commission, Florida Power and Light Co. (FPL) reported delivering 99.98 percent reliability for customers in 2010 and outlined plans for continued investment in reliability and storm preparedness in 2011.

As measured by the industry standard and according to the most recent data available, FPL customers on average experienced 81.3 minutes without power over the year, which is 32 percent better than the 2009 national average.

The average annual number of interruptions that FPL customers experienced improved to 1.21 in 2010 while the company’s average restoration time of 67.4 minutes per outage ranks second among major utilities’ 2009 performance nationwide.

One of the most frequent causes of distribution outages is vegetation—tree branches, palm fronds or other plants coming into contact with power lines. To help reduce and prevent power outages and flickers for its customers, FPL cleared vegetation from more than 13,000 miles of distribution power lines and all transmission corridors last year.

Florida is also the U.S. lightning capital, which is why FPL Lightning Lab engineers constantly test equipment and research ways to reduce its impact on the grid.

In 2010, FPL invested more than $100 million in distribution reliability programs, including vegetation management, priority feeders and overhead line inspections.

In 2011, FPL plans to clear vegetation along more than 12,000 miles of distribution power lines and to maintain a similar level of funding for reliability programs as in 2010. The company remains ahead of its long-term inspection schedules for the system’s more than 1 million distribution poles and 65,000 transmission structures. In 2010, the company inspected approximately 141,000 distribution poles and performed climbing inspections on 11,000 transmission structures.

Since 2006, FPL has inspected more than 660,000 poles throughout the distribution system, reinforcing and replacing them as necessary. In 2011, FPL plans to inspect at least another one-eighth of its distribution poles and complete the remaining first cycle of inspections on transmission structures. The projected cost of inspections and associated follow-up work this year is estimated at $80 million to $90 million.

To ensure the reliability and storm readiness of its high-voltage power lines, in 2010 FPL also upgraded 1,400 transmission structures from wood to concrete or steel and replaced ceramic post insulators on nearly 120 structures with more durable polymer post insulators. Today, the backbone of FPL’s transmission system is more than 74 percent concrete and steel.

In addition, FPL invested more than $45 million in 2010 to strengthen the distribution infrastructure serving 26 emergency dispatch (911) facilities, 12 emergency operations centers (EOCs), one hospital and five community thoroughfares, which also benefited an additional 19 critical infrastructure facilities served by these same main power lines.

By the end of 2010, FPL had strengthened the infrastructure serving every major hospital and acute care facility in its service territory and 66 percent of all 911 facilities and EOCs. In 2011, FPL plans to invest another $45 million to $55 million to continue strengthening critical areas of the system. 


Submeter-based Energy Monitoring Helps Utility Service Center Earn Gold

By Sim Gurewitz, E-Mon

As one of America’s oldest and largest electric utilities, Southern California Edison (SCE) serves more than 13 million customers in 11 central, coastal and Southern California counties. The utility recently launched a series of aggressive new measures to dramatically improve service efficiency while also increasing flexibility, reliability and responsiveness to regional power emergencies. As part of this process, Edison is constructing 10 new state-of-the-art customer service centers in various locations throughout its 50,000-square-mile service territory.

Opening for business in early 2009, Edison’s prototype high-performance service center is only slightly newer than the city in which it is located—Wildomar, Calif., incorporated in July 2008.

Four 277/480V submeters were installed next to a main switchgear cabinet outside one of the buildings.

“The new service center in Wildomar is a model of energy efficiency, environmentally friendly and vital to providing optimum service to our customers in southern Riverside County,” said Cecil House, SCE senior vice president, safety, operations support and chief procurement officer.

With two multi-level main buildings and a single-story structure in the service yard, the 97,553-square-foot Wildomar facility underscores the utility’s commitment to serving its customers while promoting energy efficiency and good environmental stewardship.

As the first of a new breed of service centers, the facility’s high-performance design was recently certified at the Gold level by the U.S. Green Building Council under its LEED high-performance building assessment system.

With two multi-level main buildings and a single-story structure in the service yard (shown above), the 97,553-square-foot Wildomar facility underscores the utility’s commitment to energy efficiency.

LEED, Green Globes and other high-performance-building assessment systems require measurement and verification of the facility’s energy envelope, a tracking function provided by the facility’s building automation system (BAS). At Wildomar, the energy data acquisition front end of the BAS is provided by electric submeters from E-Mon. Anaheim, Calif.-based Sunwest Electric, the submetering system installer at Wildomar, specified 277/480V 3-phase/4-wire E-Mon D-Mons to monitor electrical consumption (kWh) and demand (kW) on two 200A and one each 1,600A and 3,200A circuits in the three main buildings and the main switch board (see photo).

“The E-Mon D-Mons were installed to see how much power is being consumed in each building and to compare this usage to similar non-green buildings,” said John Richards, Sunwest Project Foreman. “Benchmarking the energy-efficiency measures that were implemented in this facility will serve as a prototype for other service centers in the near future.”

Now in operation for several months, the customer is satisfied with how the system is performing its energy monitoring functions as a key data gathering tool for the facility’s LEED Gold certification.

In LEED-NC certification processes like SCE-Wildomar’s, submetering equipment is useful for a variety of functions. For example, commissioning agents can use energy intelligence software like E-Mon Energy to identify functionality and performance of electric, water and gas systems. In new construction, submeters are useful for baselining facility energy performance, and in renovation scenarios where at least 12 months of energy data can be collected to provide a highly accurate profile of the using facility’s energy patterns over time.

Recent industry studies show that green building construction will continue to be a major trend across the facility landscape. Enabling technology, like submeters, can help facilities improve their bottom lines by benchmarking, measuring and verifying compliance with major energy initiative guidelines, while also encouraging every level of the enterprise to become a stakeholder in the energy management and conservation process. SCE’s new Wildomar service center demonstrates how submeters are helping state-of-the-art facilities support sustainability, improve energy efficiency and encourage environmental stewardship in the communities they serve.

Sim Gurewitz is a certified energy manager and E-Mon’s Western regional manager.

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The Clarion Energy Content Team is made up of editors from various publications, including POWERGRID International, Power Engineering, Renewable Energy World, Hydro Review, Smart Energy International, and Power Engineering International. Contact the content lead for this publication at Jennifer.Runyon@ClarionEvents.com.

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