OCTOBER 22 2014

Emera Maine’s Local System PlanNeeds Assessment/Potential Solutions

OCTOBER 22, 2014

Needs Assessment/Potential SolutionsLocal Planning Advisory Committee Meeting

Emera Maine Representative:pJeffrey Fenn, P.E., SGC Engineering LLC

Purpose of Local System Plan (LSP)

Per Attachment K – The LSP is an annual report that:D ib PTF t i i t li bilit d Describes non PTF transmission system reliability needs Reflects Local System planning studies Proposed solutions

Identifies Local planning process Criteria, Data and Assumptions

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LSP Communication

LSP is communicated via Transmission Owners Pl i Ad i C itt (TOPAC) tiPlanning Advisory Committee (TOPAC) meeting following an ISO-New England PAC meeting

The material is posted prior to the TOPAC meeting (via p p g (the ISO-New England PAC posting system)

Transmission Customers and Stakeholders have 30 d ft TOPAC t ti t id ittdays after TOPAC presentation to provide written comments for consideration by Emera Maine

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LSP Communication (continued)

Emera Maine Contact:K d O l k Kendra OverlockPO Box 932970 Illinois AvenueBangor, Maine, 04402-0932g , ,(207) 973-2895Kendra.Overlock@EmeraMaine.com

EM LSP is located at: http://www.emeramaine.com/about-us/transmission-development/local-system-plan aspxdevelopment/local system plan.aspx

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Local System Planning Process The process is “Needs Assessment” followed by

Solutions Proposals Local System needs can result from: Load Growth Sub-area reliability assessmentsSub area reliability assessments Point of delivery request from customers Generation interconnection requests (in accordance with

appropriate generator interconnection procedures)appropriate generator interconnection procedures)

Local System Plan consists of: Summary of needs assessment results Listing of criteria, data and study assumptions Identification of proposed alternatives Solution study results and selection of preferred alternative

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Solution study results and selection of preferred alternative

Criteria, Data, and Assumptions

Loads are based on the New England specific area as id d i th ISO N E l d MOD EMprovided in the ISO-New England MOD case, EM

specific forecasts and local customer needs are used to refine this

Studies use relevant assumptions regarding transmission, generation and demand resources found in the latest ISO New England Regional System Planin the latest ISO-New England Regional System Plan

Criteria follows ISO-New England as well as TPL criteria or local planning criteria as appropriate – Local criteria listed at the end of this presentation

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LSP Project List The LSP project list is a cumulative listing of proposed

transmission solutions intended to meet local needs Similar to the ISO-New England PTF RSP, the LSP

contains the status of each projectC t P j t i d id ti l ti t Concept – Project is under consideration as a solution to a partial needs assessment Proposed – Needs assessment completed and project proposed

l ti b t t f ll b d t das a solution, but not formally budgeted Planned – Formally budgeted and if necessary, approved by

ISO-New England Under Construction – Significant engineering and internal

approvals in process and project is being implemented In-Service – Project used and useful

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LSP - Needs

Need Needs Assessment Service Area Potential Solutions Year of Need

QP478 Interconnection study

Transmission upgrades to support proposed generation

Washington County Under study 6/2015

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LSP – Concept Status

Need Needs Assessment Service Area Project Name Status Solutions

Project In-Service

Month/YearMonth/Year

Reliability Line 74 Condition Bangor Line 74 Study

L74 Rebuild/Reconductor

12/2016

L50 condition L50Reliability and support of

area load growth

Bangor Corinth Village support Study

L50 Rebuild/Reconductor

12/2016

ReliabilityL70 condition and Thermal Bangor Line 73 Study

L73 Rebuild/Recon 12/2016y

and Voltageg y

ductor

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LSP – Proposed Status

Need Needs Assessment Service Area Project Name Status Solutions Project In-

Service

E t B 46kV li

Reliability

Eastern Bangor load requirements including hospital

Bangor Waterworks substation Proposed

46kV line extension and load serving substation

12/2016

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LSP – Planned Status

Need Needs Assessment Service Area Project

Name Status Solutions Project In-Service

Li 13Reliability Line 13 Condition Downeast

Line 13 Rebuild E Franklin east

Planned Rebuild 12/2015

Reliability Line 5 Overload Bangor T9L/501 line Planned Rebuild 0.25 mi 12/2014

Reliability

Improve area reliability, support MDI loads, defer L32 loading issue and improve Downeast MDI reliability Planned

Additional 34.5kV circuit with diverse route Part of

12/2016pability to maintain transmission circuits

route. Part of area looping

Reliability Line 8 Condition d l di Bangor Line 8

R d t PlannedLine 8 reconductor 06/2015e ab y and loading a go Reconductor a ed eco duc osections

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LSP – Under Construction Status

Need Project In-Service Service Area Project Name Status

Reliability 12/2014 Northern Chester T3 Addition Under ConstructionReliability 12/2014 Northern Chester T3 Addition Under Construction

Reliability 12/2014 Northern Line 87 Rebuild Under Construction

Reliability 12/2015 Bangor Line 75 Rebuild/reconductor Under Construction

Reliability 12/2014 Downeast L13 from E Franklin west rebuild Under Construction

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LSP – In-Service

Need Project In-Service Month/Year Service Area Project Name Status

Nothing to report

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Maine and Emera Maine Major Transmission SystemMajor Transmission System

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Emera Maine Detailed System

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Project Descriptions - Needs

Queue 478 Interconnection – 10MW wind i t ti t th EM bt i i iinterconnection to the EM subtransmission in Washington County

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Project Descriptions - Needs

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Project Descriptions - Concept

Line 74 Rebuild/Reconductor– condition of existing f iliti d th l d lt i 46kVfacilities and thermal and voltage issues on 46kV system

Line 50 Rebuild/Reconductor – Condition based need for rebuild as well as thermal and voltage issues

Line 73 Rebuild/Reconductor – Condition based need f b ild ll th l d lt ifor rebuild as well as thermal and voltage issues

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Project Descriptions - Concept

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Project Descriptions – Proposed

Waterworks Substation – new 46/12.5kV substation as ll h t 46kV li t i t th l lwell as short 46kV line extension to serve the local

Eastern Bangor load as well as hospital expansion

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Project Descriptions - Proposed

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Waterworks Substation

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Project Descriptions - Planned

Line 13 Rebuild – E. Franklin east Line 5 – T9L/501 Rebuild 0.25 miles MDI Reliability – additional 34.5kV circuit with diverse

routeroute. Line 8 Reconductor – segment and related switching

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Project Descriptions - Planned

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Line 13 Rebuild – E. Franklin east

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Line 5 Rebuild – T9L/501

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MDI Reliability

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Line 8 Reconductor

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Project Descriptions –Under ConstructionUnder Construction

Chester T3 Line 87 Rebuild Line 75 Rebuild/Reconductor Line 13 from E Franklin west Rebuild Line 13 from E. Franklin west Rebuild

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Project Descriptions –Under ConstructionUnder Construction

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Chester T3

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Line 87 Overload

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Line 75

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Line 13 E. Franklin west

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Local System Planning Criteria

The transmission system for purposes of this study is defined as those system facilities that are operated at 34.5kV and above and are not considered to be under ISO-NE planning (in general non PTF).

The standard of service to be provided dictates the need for changes to the existing system. It is necessary to consider the capability of transmission system elements, possible equipment failures, and the impact of failures on the ability to serve area p q p , p yloads.

Transmission equipment is designed to operate within certain capabilities. The power that may be transferred over transmission lines depends upon the current carrying capacity of the wire and/or the required clearances of lines above groundcarrying capacity of the wire and/or the required clearances of lines above ground. Transformers are limited by their heat dissipation capability. Circuit breakers or switches are designed to sustain a certain continuous amount of current. Also, the operation of customer electrical equipment requires that voltage be maintained within a certain acceptable range Transmission system facilities are capable ofwithin a certain acceptable range. Transmission system facilities are capable of regulating voltage within a limited range by varying reactive power and changing transformer tap settings.

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Local System Planning Criteria

Since all equipment is subject to breakdown, it is necessary to consider the consequence of such failures. One possible outcome could be the overload of other equipment that remains in service. For example, if one of two parallel lines trips, the remaining line may become overloaded. Overload beyond emergency ratings must be avoided due to possible permanent damage to the equipment or for public safety. Another consequence of equipment failure is the loss of power supply to customer load. This could occur with the loss of a radial transmission line or as the result of the cascaded outage of a looped transmission system. The loss of supply is critical to loads such as industrial processing, home heating, and hospitals, and must be considered in the design of the transmission system.

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Local System Planning Criteria

CAPACITY CRITERION No facility is to be loaded in excess of its normal rating for any expected dispatch ofNo facility is to be loaded in excess of its normal rating for any expected dispatch of

system generation at any load level. For any single contingency, no facility is to be loaded in excess of its normal rating for the following load cycle or in excess of its emergency rating immediately following the contingency,. Uneconomic generation dispatch may be utilized to maintain power flows within ratings following adispatch may be utilized to maintain power flows within ratings following a contingency.

VOLTAGE CRITERION Transmission system voltages are to be maintained between 95% and 105% of

foperating base voltage under normal system conditions and for any single contingency. Further, voltages on the regulated side of load serving buses are to be maintained between 100% and 105% of operating base voltage under normal system conditions.

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Local System Planning Criteria

LOSS OF LOAD CRITERION No loss of load in excess of 25 MW is to occur for any single contingency Loss ofNo loss of load in excess of 25 MW is to occur for any single contingency. Loss of

load less than 25 MW should be resupplied within 24 hours, except under very adverse conditions.

MAINTENANCE CRITERION Transmission system planned maintenance is to be possible without exceeding

normal voltage and capacity limits and without loss of load.

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Questions?

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