OCTOBER 2, 2013 Maine 2013 Outage Coordination Redacted Copy

Agenda Welcome, Introductions and Safety Expectations and Goals for Meeting MPRP Project Update Other CMP/BHE Projects Specific Outage Discussion, Key Fall 2013/Spring 2014 outages Questions Redacted Copy 2

Expectations/Goals Communicate significant planned 2013 Maine transmission equipment outages that could impact generation constraints Communicate specific outage coordination changes to limit impact on potential generation constraints Respond to outage coordination questions from the audience Redacted Copy 3

MPRP Project Statistics 452 miles of new or rebuilt 345kV and 115kV Transmission 183 miles of new 345kV Transmission 105 miles of new 115kV Transmission 5 miles of Rebuilt 345kV Transmission 140 miles of rebuilt 115kV Transmission 8 miles of rebuilt 34.5kV Sub Transmission 11 miles of 345kV and 115kV line terminations 5 new Greenfield Substations Albion, Coopers, Monmouth, Larrabee, Raven 6 Major Substation expansions Maguire, South Gorham, Surowiec, Gulf Island, Belfast, Livermore Falls 50 Remote end substation expansions or modifications 60 - Transmission line crossings Redacted Copy 4

Northern Loop Construction Construction Status – Albion Road Substation energized – All 115kV lines terminated into station – Construction of new 345kV line from Orrington to Albion Road – Various 115kV rebuilds Near term construction activities – Continued rebuild of two new 115kV lines and construction of a new 115kV line – Mechanical completion of Coopers Mills Road Substation Future construction activities – Completion of 115kV construction – Construction of new 345kV line – Energization of Coopers Mills Road Substation 5 Redacted Copy

Central Loop Construction Construction Status – Larrabee Road Substation energized – Construction of new 345kV line from Larrabee Road to Surowiec – Various 115kV rebuilds Near term construction activities – Continued rebuild of two new 115kV lines and construction of a new 115kV line – Energization of Gulf Island Substation – Energization of Livermore Falls Substation – Mechanical completion of Coopers Mills Road Substation Future construction activities – Completion of 115kV construction – Construction of new 345kV line – Energization of Coopers Mills Road Substation Redacted Copy 6

Southern Loop Construction Status – Raven Farm Substation mechanical completion – Various 115kV rebuilds Near term construction activities – Continued construction of 345kV line from Surowiec to Raven Farm – Energization of Raven Farm Substation – Mechanical completion of Maguire Road Substation – Energization of Surowiec Substation expansion Future construction activities – Completion of new 345kV line – Energization of Maguire Road Substation – Final energization of Eliot Substation Redacted Copy 7

CMP/BHE Capital and Maintenance Work Other Non-MPRP CMP Capital and Maintenance Work that affects the transmission system – Transmission Line Structure Replacements both Capital and Maintenance – System Planning related Substation rebuilds or expansions to support future reliability needs – Substation equipment replacements or upgrades to address maintenance concerns – Transmission Line re-rates or rebuilds to increase capacity – Substation maintenance equipment inspections and relay testing – Regulatory required relay and equipment trip checks Redacted Copy 8

CMP Outage Applications Central Maine Power had 1,200 outage applications in 2012 There have been 1,244 transmission (>34.5kV) and 641 sub- transmission (34.5kV) outage applications in 2013 The MPRP Project has submitted 761 outage applications for the project through October 2, 2013 The outages range in duration from a few hours to eleven months in length The MPRP team anticipates that there will be an additional 500 – 600 outages needed to finish the program Redacted Copy 9

Maine 2013 Transmission Outages Changes to plan typically result in increased construction cost – Costs include overtime, additional contractor resources, expedited material, additional engineering and outage coordination resources, environmental mitigation, schedule and remobilization costs, permitting, etc. Outages that have the potential for significant impact to generators in 2013 will be discussed – Long (greater than one week) duration outages – Significant potential generation constraints Redacted Copy 10

TRANSMISSION SYSTEM LIMITATIONS All facility in and single facility out conditions Redacted Copy

Transmission System Limits Impact On Generation Constraints Redacted Copy 12

Transmission System Limits Impact On Generation Constraints Redacted Copy 13

2013 Maine Major Outages 115 kV Outage Condition B Western Maine – 3 rd Qtr 2013 – 4 th Qtr 2013 ~ 3 month duration – 1 st Qtr 2014 ~ 2 week duration 115 kV Outage Condition C Western Maine – 3 rd Qtr 2013 ~ 3 week duration 345/115 kV Outage Condition F Northern Maine Area – 4 th Qtr 2013 ~ 1 week 345 kV Outage Condition G Northern Maine Area – 3 rd Qtr 2013 ~ 1 week 345 kV Outage Condition H Northern Maine Area – 4 th Qtr 2013 ~ 2 weeks Redacted Copy 14

2013 Maine Major Outages (cont.) 345 kV Outage Condition I Northern Maine Area – 3 rd and 4 th Qtr 2013 ~ 4.5 weeks 345/115 kV Outages Condition J Southern Maine Area – 3 rd Qtr 2013 – 4 th Qtr 2013 ~ 2.5 months 115 kV Outages Condition K Central Maine Area – Multiple outages – 4 th Qtr 2013 ~ 3 weeks – 1 st Qtr 2014 ~2.5 months – 2 nd Qtr 2014 ~ 3 weeks 345 kV Outage Condition L Northern Maine Area – 1 st and 2 nd Qtr 2014 ~ 7 weeks Redacted Copy 15

115 kV Outage Condition B Western Maine – Original Plan – 1 st Outage Redacted Copy 16

115 kV Outage Condition B Western Maine – Alternatives – 1 st Outage Purchase additional ROW to eliminate/reduce duration of outages – Too expensive for project – Siting and permitting delays Utilize more expensive construction techniques to reduce duration of Outage Condition B by 2 months – Implemented Utilization of a temporary SPS to increase limits for both outages – Eliminated Western Maine Export Interface limit – Increased Inner Rumford Export Interface limit – Increased Outer Rumford Export Interface limit – RPA could operate – Implemented RPA installed a Power System Stabilizer – Increases interface limits that are a limited by damping Do not take outages during the summer months – System operational capacity needs Re-sequence work in order to implement alternatives – Outage was delayed more than 12 months Updated generator dynamic models received Redacted Copy 17

115 kV Outage Condition B Western Maine – Current Plan – 1 st Outage Redacted Copy 18

115 kV Outage Condition B Western Maine – Original Plan – 2 nd Outage Redacted Copy 19

115 kV Outage Condition C Western Maine Redacted Copy 20

115 kV Outage Condition C Western Maine Redacted Copy 21

345/115 kV Outage Condition F Northern Maine Redacted Copy 22

345 kV Outage Condition G Northern Maine Area - Original Plan Redacted Copy 23

345 kV Outage Condition G Northern Maine Area - Current Plan Redacted Copy 24

345 kV Outage Condition H Northern Maine - Current Plan Redacted Copy 25

345 kV Outage Condition H Northern Maine - Current Plan Redacted Copy 26

345 kV Outage Condition I Northern Maine Redacted Copy 27

345 kV Outage Condition I Northern Maine Redacted Copy 28

345/115 kV Outage Condition J Southern Maine Redacted Copy 29

115 kV Outage Condition K Central Maine Redacted Copy 30

345 kV Outage Condition L Central Maine Redacted Copy 31

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