National Grid nears completion of a challenging component of the New England East-West Solution suite of transmission projects.
The Rhode Island Reliability Project soon will be improving transmission system reliability for 480,000 Rhode Island electric customers. This follows placement of 25,000 cu yd (19,114 cu m) of concrete and 5 million lb (2.27 million kg) of reinforcing steel in 743 foundations, erecting 15 million lb (6.8 million kg) of tubular steel structures, stringing 250 miles (402 km) of conductor and performing extensive improvements at multiple substations.
The Rhode Island Reliability Project is one of four major components of the New England East-West Solution (NEEWS), conceived by a working group with members from National Grid, Northeast Utilities and ISO New England. NEEWS is one of the largest power delivery projects to be undertaken in New England in more than 30 years. The four major components of NEEWS were developed as a coordinated solution to address multiple southern New England transmission system constraints by creating new 345-kV ties between existing hubs in the transmission network and upgrading numerous existing transmission line and substation facilities.
National Grid's Rhode Island Reliability Project is comprised of 26 separate component projects. The centerpiece is a new 21-mile (34-km), 345-kV transmission line along an established transmission corridor from West Farnum Substation, located in North Smithfield, Rhode Island, U.S., to the Kent County Substation, located in Warwick, Rhode Island.
To fit the new 345-kV line on an already built-out 250-ft (76-m)-wide right-of-way (ROW), extensive reconstruction of two existing 115-kV lines was necessary. The transmission line work has proven to be the most visible part of the Rhode Island Reliability Project. Despite the addition of the new 345-kV circuit on the corridor, the project will result in an updated and streamlined ROW appearance, as well as improved reliability, maintainability and accessibility of the facilities located there.
Along with the challenges posed by the tight quarters of the existing ROW, eight load-serving substations and two generators are connected to the 115-kV lines, which had to be reconstructed, significantly complicating the outage planning and work sequencing for the project. Additionally, most of the transmission line route also is occupied by a natural gas transmission pipeline operated by Tennessee Gas Pipeline, a subsidiary of Kinder Morgan.
The requirements of working safely to install reinforced concrete foundations within 15 ft (4.6 m) of the gas pipeline, coordinating the numerous outages to allow construction of the relocated and new facilities, and dealing with rough terrain and difficult ground conditions all presented significant project challenges. To meet these challenges National Grid assembled a highly qualified and experienced project team comprised of internal staff and consultants.
National Grid assumed a lead role for project management, project licensing and permitting, and stakeholder relations. POWER Engineers served as National Grid's owner's engineer, performing detailed engineering and providing support in the areas of material and equipment procurement, construction inspection, commissioning and document management. POWER Engineers was selected as the owner's engineer based on its staff qualifications, competitive rates, resource availability and collaborative client approach. Other key team members included Vanasse Hangen Brustlin Inc. for permitting and environmental compliance support, Energy Initiatives Group for outage planning and project management support, and New Energy Alliance (a joint venture of Balfour Beatty and MJ Electric) for construction.
The integrated team assembled for the Rhode Island Reliability Project was able to identify, manage and mitigate potential risks to the complex project, whether arising from the loss of planned outages, challenging ground conditions impacting foundation designs, or the need for special construction practices and controls to provide for the safe drilling of foundations adjacent to the natural gas pipeline.
From the outset of NEEWS, it was realized in-house resources would be spread too thin to execute a project of this scope and magnitude, especially with all of the other system improvements planned and in progress at National Grid. A project delivery model was developed that would preserve National Grid's ability to provide high-level management and oversight from talented subject-matter experts while leveraging the deep bench of engineering and project delivery expertise of an organization like POWER Engineers.
The Rhode Island Reliability Project required a sharp focus on safety from both the engineering and construction perspectives, strong commitment to environmental stewardship and compliance, and an overarching objective to manage this significant construction in a manner that would preserve the reliability of the network and service to customers.
Safety, Safety, Safety
With up to 19 foundation drill rigs operating along the project ROW at any point in time, National Grid recognized it would be necessary to put strong controls in place to ensure that foundation construction would be performed in a safe and secure manner. These controls were especially critical due to the presence of the natural gas pipeline and the nearby energized transmission lines.
National Grid and Kinder Morgan developed a cooperative work plan that provided specific requirements and procedures necessary for safely performing work adjacent to the natural gas pipeline. Every worker on the project received initial gas pipeline safety training and ongoing refresher training by Kinder Morgan. To date, more than 1,000 training sessions have been conducted.
At the outset of the project, the location of the pipeline was clearly marked and delineated in the field for its entire length along the project ROW. Additionally, a series of improved equipment-crossings were installed along the pipeline. At these locations, the pipeline was excavated and backfilled with flowable concrete to facilitate the safe passage of construction equipment across the pipeline. These crossing locations also were clearly marked in the field, delineated on the project plans and monitored by Kinder Morgan inspectors.
The project team also developed a “Permit to Drill” process that involved a series of checks, confirmations and sign-offs from all parties before drilling at any location was allowed to commence. National Grid performed a Process Hazard Analysis to examine any work activity or situation that could possibly introduce a safety risk into the construction process, and then developed appropriate mitigation measures to address and eliminate those exposures.
Other elements of the safety approach implemented by National Grid for the Rhode Island Reliability Project included the publication of a project-specific safety handbook and the use of real-time vibration monitoring for any foundation drilling that was proximate to the pipeline. The end result was a rigorous program of tools, training, controls and monitoring to ensure safe transmission line construction adjacent to the natural gas pipeline and the energized transmission circuits.
The Rhode Island Reliability Project required significant upgrades to several substations in Warwick, including the Kent County Substation located at the southern terminus of the new 345-kV transmission line. Work at the Kent County Substation included a yard expansion and the installation of two new 345/115-kV autotransformers. The project also included the construction of two new 345-kV breaker-and-a-half bays, two new 115-kV breaker-and-a-half bays, two new 115-kV capacitor banks and a new 345/115-kV control building to house new protection and control equipment for the entire 345/115-kV station. The protection and control upgrades included the installation of two independent and redundant protection systems for each network element. In addition, two existing 115-kV bays and bus work were rebuilt and upgraded.
Substantial upgrades and additions also were made at National Grid's 345-kV West Farnum Substation in North Smithfield, Rhode Island. Much of the existing 345-kV equipment was upgraded to address the increased fault duty requirements and existing thermal limitations, while the additions were made to accommodate the three new 345-kV transmission lines, the centerpieces of the NEEWS project.
Because the existing substation site is constrained by property limitations and surrounding wetlands, expansion of the substation footprint was not feasible. As a result, National Grid employed gas-insulated substation (GIS) technology to make the most of the existing space. The existing 345-kV air-insulated, five-position ring bus was replaced by a gas-insulated, eight-position four-bay breaker-and-a-half configuration, which was all accomplished within the existing footprint while keeping the existing station fully operational. Two new buildings were also constructed at the site — one to house the GIS equipment and the other to house the protection and control equipment.
Communication capability between substations is also being upgraded as part of the Rhode Island Reliability Project, with the installation of optical ground wires on the new 345-kV transmission line and several existing 115-kV transmission lines.
Each of the 115-kV transmission lines being reconstructed as part of the Rhode Island Reliability Project is tapped into eight load-serving substations. As such, careful planning and a phased construction approach were required to reconstruct the main lines and modify the tap lines while maintaining dual supply to the substations to the fullest extent possible for reliability purposes. National Grid's outage coordinators and project team looked at the collection of all 26 component projects and produced an integrated and coordinated outage plan that took advantage of project synergies and overlapping requirements between work sites.
The Rhode Island Reliability Project began construction in late 2010 and is now nearing completion, with the final elements scheduled to be placed into service in April 2013. The transmission line ROW has taken the form envisioned by the project team in the early planning stages of the massive project.
With the completion of the Rhode Island Reliability Project fast approaching, the success of NEEWS to date is a testament to the teamwork and problem-solving approach adopted by National Grid, POWER Engineers and the other consultants on the NEEWS team. All of the companies have worked side by side to implement and execute a program strategy founded on effective planning and efficient designs to allow for the timely and safe construction of the new overhead transmission line and substation facilities.
The NEEWS Rhode Island Reliability Project is what a truly collaborative working relationship is like. Each company has acted as part of a unified and integrated project team with shared objectives, rather than as individual companies with separate goals. This way, the sum is truly greater than the parts, which, ultimately, will benefit National Grid's customers.
Engineering and planning continue for the forthcoming Interstate Reliability Project portion of NEEWS, and the project team is poised to continue this collaborative approach, capitalizing on past accomplishments and lessons learned to further enable the program's success on behalf of National Grid's customers. The Interstate Reliability Project is moving steadily through the licensing and permitting processes in the states of Massachusetts, Rhode Island and Connecticut, and construction of this next phase of NEEWS is anticipated to begin in early 2014.
David Beron (email@example.com) is National Grid's principal project manager for the New England East-West Solution collection of work. Beron has 25 years of experience in the engineering and management of large-scale transmission infrastructure projects. He is a registered professional engineer in Rhode Island and a certified project management professional.
Andrew Alexiades (firstname.lastname@example.org) is a program manager with POWER Engineers for the New England East-West Solution portfolio of projects. Andrew earned a BEEE degree from Stevens Institute of Technology in New Jersey, U.S. A member of IEEE and Project Management Institute, he has served in numerous project management roles within the energy industry for more than 35 years, including areas of power generation and power delivery both domestically and internationally.
Scott Ryder (email@example.com) is a registered professional engineer with more than 40 years experience in the electric power transmission business. He began his career with National Grid and now serves as a consulting engineer with Energy Initiatives Group specializing in transmission line project management.
Balfour Beatty | www.balfourbeatty.com
Energy Initiatives Group | www.eig-llc.com
ISO New England | www.iso-ne.com
Kinder Morgan | www.kindermorgan.com
MJ Electric | www.mjelectric.com
National Grid | www.nationalgridus.com
Northeast Utilities | www.nu.com
POWER Engineers | www.powereng.com
Vanasse Hangen Brustlin | www.vhb.com