Maine regulators reviewing proposals, including 138-kV, 345-kV lines, to address reliability issues

Proposed projects being reviewed by Maine state regulators to address electric reliability issues in the Northern Maine Independent System Administrator (NMISA) region include a 138-kV line by Emera Maine, a 345-kV line by Central Maine Power (CMP) and a 345-kV line by New Hampshire Transmission.

The Maine Public Utilities Commission (PUC) on Jan. 13 issued an order denying Maine Public Service’s (MPS) motion for a protective order related to information about its proposed plans to address reliability issues in Northern Maine.

According to Emera Maine’s Jan. 17 filing with the PUC, Emera Maine is the successor by merger to MPS.

Temporary protection was provided in the Jan. 13 order to information provided by Loring Holdings LLC to MPS on a confidential basis, the PUC said.

Several parties filed timely oppositions to MPS’s motion, including Eastern Maine Electric Cooperative, Van Buren Light & Power, the state Office of the Public Advocate (OPA) and CMP.

Emera Maine, in its Jan. 17 proposal, said that since its preferred solution involves the construction of a new transmission line connection to the New Brunswick transmission system, a certificate of public convenience and necessity (CPCN) will be required before construction. Emera Maine will issue a final reliability plan after additional input from stakeholders and the Northern Maine Planning Advisory Group (PAG), and following approval from its board of directors.
Emera Maine also said that it plans to file its CPCN application with the PUC by March 31.

According to the proposal’s Attachment A, the proposed solution includes a new 138-kV transmission line from Woodstock, New Brunswick, to the Maine Public Service (MPS) Lines 6910 and 6920.

The solution requirements entail:

  • Transmission upgrade requirements
    – New Brunswick system requirements such as rebuilding at the Woodstock
      substation for 138-kV line interconnection
    – MPS system minimum requirements such as adding a capacitor bank at the Flo’s
      Inn substation
  • Transmission operating requirements for the New Brunswick system
  • Confirmation of capacitor banks in service required for the New Brunswick system

According to the proposal’s Attachment B, or briefing paper, Emera Maine, in reaching its conclusions, considered a great deal of information including past technical and market studies, previous regulatory proceedings, new technical analysis of the current reliability situation in Northern Maine, and input obtained through the stakeholder and PAG consultations and the PUC Northern Maine Reliability NOI process.

“[C]onstructing a new 138kV transmission tie line to connect the New Brunswick Power system near Woodstock to Emera Maine’s transmission system north of Houlton, along with a number of smaller changes to both systems, will meet Emera Maine’s long term reliability criteria at a lower cost to Emera Maine and other Northern Maine electricity customers than the in-region generation options, or the options involving connection to the [ISO New England (ISO-NE)] grid,” Emera Maine said. “Both transmission cost and supply cost effects were considered in the analysis.”

According to the proposed schedule, the project would be in service in 2017.

Central Maine Power

According to the Jan. 17 proposal filed on behalf of CMP, the company proposes to build the Maine Power Connection (MPC), that is, a new 26-mile, 345-kV line between the existing Maine Electric Power Company (MEPCO) line in the Haynesville, Maine, area to a new 345-kV substation near the existing Mullen substation in Houlton, Maine.

The proposed transmission solution would require a CPCN.

Presentations at a September 2013 meeting of the PAG indicate that a 345-kV interconnection between the northern Maine transmission system of Emera Maine and the ISO-NE administered transmission system is likely the most robust solution to the identified reliability needs in northern Maine.

One difference between the MPC and Emera Maine’s proposed solution is that, in addition to addressing the identified reliability needs, a 345-kV connection between the northern portion of Emera Maine’s transmission system and the ISO-NE system would also open northern Maine to a larger power supply resource base than currently available and would provide generators in northern Maine, including large, new renewable generation facilities currently in development, access to a larger market, the company added.

“Thus, not only would CMP’s proposed solution address the reliability issues plaguing northern Maine, it would also bring a competitive market to the northern Maine region,” according to CMP.

The current desire of southern New England states to access northern Maine renewable resources, as shown by the long-term power purchase agreements recently approved by regulators in Connecticut and Massachusetts, presents an opportunity and leverage for Maine to negotiate a fair transition that mitigates the transmission and ISO-NE cost impacts on northern Maine customers of the northern portion of Emera Maine joining ISO-NE.

CMP also said that while additional studies will be required to address any interconnection to the ISO-NE grid, system study results completed to date, including steady state, stability and extreme contingency analysis, indicate that the proposed project would not have an adverse effect on the ISO-NE administered transmission system.

The MPC would use the existing right of way (ROW) known as the Bridal Path, a substation site under option by CMP in Haynesville, and a short section of new ROW adjacent to the MEPCO corridor between the end of the Bridal Path and the new Haynesville substation, soon also to be under option by CMP.

The proposed project is expected to cost about $152m based on CMP’s recent experience building similar transmission lines and substations, the company added, later noting that the cost range for the project is $114m to $228m, with the midpoint estimated cost at about $152m.

In general, the proposed new line will be built using two-pole wood H-frame-type structures at tangent structure locations.

CMP is a subsidiary of Iberdrola USA, which is a subsidiary of Iberdrola S.A.

Loring Holdings

In its Jan. 17 proposal, Loring Holdings said its proposed project consists of a twin-turbine, gas-fired cogeneration facility, the design and construction of a 180-mile natural gas pipeline from Winterport, Maine, to Limestone, Maine, ending at the Loring Commerce Centre, and the expansion of natural gas infrastructure in Northern Maine.

The combined heat and power facility (Loring CHP) will be capable of supplying electricity to the local transmission and distribution utility, as well as providing electricity and steam to co-located offtakers on a contractual basis.

A system impact study was completed using an earlier project specification, with minor local transmission upgrades required. Loring also said that a new interconnection request and system impact study is expected to be final in 2Q14.

The natural gas pipeline will use an existing ROW held by Loring from a point of intersection with the Maritimes and Northeast Pipeline in Winterport, north 180 miles to its termination at the Loring Commerce Centre in Limestone.

Initial environmental permitting work has begun, including vernal pool and wetland studies on significant portions of the corridor, and all environmental studies are scheduled to be completed this year. Permits for the pipeline will be submitted by November, Loring added, noting that under the current project schedule, the pipeline will be completed and operational by 4Q16.

While the specific terms and pricing of the Loring bid in docket 2012-00504 are to remain confidential, the concept, Loring said, is simple, noting, for instance, that electric ratepayers, on the supply side of their monthly bills, will cover the cost of fuel used to generate electricity and the cost of the Loring CHP operations and maintenance only. Natural gas ratepayers, the businesses and residents who choose to convert their heating fuel to natural gas, will cover, through a “cost of gas adjustment” rate, the cost to build the Loring CHP, necessary to anchor natural gas infrastructure, the cost to build the pipeline and the cost of the pipeline operations and maintenance.

This cost-sharing between electric and natural gas ratepayers, a concept being considered in ISO-NE rate structures, will enable a net energy savings of more than $50m on an annual basis, with no impact on transmission costs and no interconnection with ISO-NE required, Loring added.

“Transmission upgrades alone only increase our dependency on a foreign nation for generation, thereby decreasing our system security,” Loring said. “This is further complicated by the fact that since Maine deregulated, international mergers and acquisitions have left the fox guarding the chicken coop as both generation and transmission in northern Maine are effectively controlled by foreign nationals.”
Noting that its proposal will have zero effect on 10-year levelized transmission costs, Loring said it “believes that gas-fired in-region generation was and is the best long-term solution for northern Maine’s reliability program.”

New Hampshire Transmission

New Hampshire Transmission was among those filing with proposals, saying in its filing that it proposes the Northern Maine Reliability Tie, which would connect Northern Maine to the ISO-NE transmission system through a 26-mile, 345-kV line between the Mullen substation and Haynesville.

While the project’s primary driver is to solve reliability problems in Northern Maine identified by the PUC, New Hampshire Transmission said its project will also bring additional benefits including adding resource diversity and providing local Northern Maine generation a new market to sell power; providing economic benefits, primarily jobs and taxes, to Northern Maine; and promoting the long-term development of one of the richest wind resources in New England, which will enable additional investment in Maine.

The solution to Northern Maine’s reliability and competitive market problems can be addressed using the existing transmission corridor, the Bridal Path, “but MPS has let the Bridal Path lie dormant and other prospective developers have been unable to successfully see the project to finally come to fruition,” New Hampshire Transmission said.

The company said that its proposed project would primarily follow an existing, but unused, ROW, and the expected commercial operation date based on the regulatory approval process proposed by New Hampshire Transmission is mid-2017.

If it is unable to obtain the rights to the Bridal Path, New Hampshire Transmission said it would move forward by developing a ROW adjacent and parallel to the Bridal Path, allowing it to avoid the need to create an entirely new corridor.

The line will be built on two-pole wood H-frame-type structures at tangent structure locations.

The project will include new substation locations at:

  • New Mullen 345-kV substation: The substation will include a 345-kV/69-kV autotransformer. The 345-kV circuit from Haynesville will end at the substation.
  • New Haynesville 345-kV switchyard: The switchyard will be a ring bus design and will accommodate the termination of the new Mullen 345-kV circuit and the termination of the existing line segment from Haynesville to Keene Rd., and Haynesville to Keswick.

The construction cost estimate for the project is about $51.5m, of which about $26m is associated with transmission line work and $25.5m is associated with substations, the company added. The total cost estimate for the project is $59.4m.

Among other things, the company said that the proposed project will provide Northern Maine market participants with direct access to ISO-NE, reducing the risk to Northern Maine consumers and suppliers of over-dependence on New Brunswick energy supplies and transmission access charges through New Brunswick.

New Hampshire Transmission is part of NextEra Energy (NYSE:NEE).

About Corina Rivera-Linares 3277 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 16 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at