1. Presentation to FERC’s Northeast Energy Infrastructure Conference Electricity Infrastructure in New England Stephen G. Whitley Sr. Vice President and Chief Operating Officer ISO New England Inc. January 31, 2002

2. 2 Overview of Remarks ISO New England - Who we are and what we do Supply outlook Natural gas issues Regional transmission planning process Southwest Connecticut Conclusions

3. 3 ISO Agreement Who is ISO New England and what do we do? INDEPENDENT system operator based in Holyoke, MA Private, not-for-profit corporation created according to FERC principles in 1997 Responsible for system reliability and administration of the wholesale electricity markets and the regional transmission tariff ISO operates under an agreement with NEPOOL

4. 4 Supply Additions Appear Strong in Relationship to Demand Growth Projected Cumulative Summer Supply Additions over 1998 Cumulative Increase in Summer Peak Demand over 1998 MW

5. 5 Gas Pipelines Have Insufficient Capacity for Power Plant Use Shortfalls in deliveries to electric generation sector could begin as early as this winter. No impacts to traditional gas LDC operations/customers. Potential gas contingencies assessed for impacts on electric generation sector. Dual fuel units switching to oil mitigates any potential delivery shortfalls. 0 1,000 2,000 3,000 4,000 MW 2001/20022002/20032004/2005 Phase I HighPhase II ReferencePhase II High Gas-Fired MW at Risk

6. 6 Regional Transmission Expansion Plan (RTEP) ISO-NE-led effort involving both New England transmission owners and a diverse group of stakeholders First phase (RTEP01-Oct. ‘01) represents initial assessment of reliability and economics of New England system Goals of analysis: –Assess system adequacy both regionally and sub-regionally –Identify transmission constraints –Communicate the status of planned transmission upgrades –Estimate costs of congestion to consumers –Attract a market response (generation, transmission, load response)

7. 7 High Case $600M High Case $600M Low Case $125M Low Case $125M Transmission Bottlenecks are Increasing Projected Annual Costs of Congestion RTEP01, 2002-06

8. 8 Priority One: SW Connecticut Transmission System History and Background 345 kV loop originally proposed in 1970s postponed due to: –Fluctuations in economy and load growth –115 kV system improvements –High coordination of local generator and transmission maintenance Loads increased 25% in 1990s Sale of existing generators resulted in loss of control of optimum coordination of local generator and transmission maintenance More uncertainty surrounding future availability and performance of local generation Cross Sound Cable (Trans-Energie merchant facility) approved by Connecticut Siting Council; 300 MW connection to Long Island

9. 9 345kV Transmission Proposal Material on this page is consider Non-Internet Public (NIP) You would like a copy of this slide, please contact: Public Reference Room Telephone: 202-502-8371 Toll-free 1-866-208-3676 Email: public.referenceroom@ferc.govpublic.referenceroom@ferc.gov

10. 10 In closing... Supplies in New England are adequate, however, ‘deliverability’ is at issue –Transmission bottlenecks are increasing the cost and decreasing the reliability of electricity production and delivery Natural gas requirements for power generation increasing; current pipeline system cannot supply all power plant requirements on coldest days Regional transmission planning is key to success of the regional marketplace Southwest Connecticut requires action NOW

11. 11

12. Background Information

13. 13 MWCuml. Generation installed in 1999 355355 Generation installed in 2000 1,7382,093 Generation installed in 20011,5703,663 Expected 2002 & beyond (under construction)6,1209,783 Planned 2002 & beyond (NOT under construction)1,58411,367 Generator Construction is Robust as of 1/1/2002, Summer Ratings Supply Outlook

14. 14 History and Background Formation of the New England Gas/Electric Discussion Group in 1991 to examine regional coordination issues between the gas & electric industries –Examine operational reliability of the gas/electric infrastructure –Increase coordination between the industries –Educate industry participants and observers 1993 EPRI report includes the modeling of the loss of a major gas & non-gas fired generator, under projected 1995 system conditions Seven years pass with no similar analysis Gas Study

15. 15 Why a Gas Study? Since 1997, ISO-NE has received applications for interconnection System Impact Studies for almost 55,000 MW of new merchant generation capacity Virtually all of this newly proposed capacity is advanced combined cycle technology or peaking capacity fueled exclusively by natural gas There is a need to review the natural gas pipeline infrastructure in New England and its ability to reliably meet the increasing demand of the power generation sector (deliverability study) Gas Study

16. 16 Scope of Study Study time frame: 2001 - 2005 Analysis of existing pipeline infrastructure (Phase I) Analysis of expected pipeline infrastructure additions (Phase I & II) Develop a steady state hydraulic engineering model of the pipeline systems serving the NEPOOL region (Phase I & II) Analyze impacts of Reference and High Case natural gas demand consumption (Phase I & II) Conduct sensitivity analysis and transient analysis (Phase II) Summarize results and issue report with recommendations Gas Study

17. 17 Phase I Steady-State Modeling Results Issued February 2001 No pipeline delivery constraints on a peak day in Winter 2000-01 No summer peak day pipeline deliverability constraints through 2005 Gas delivery constraints become apparent in Winter 2003 –Shortfall in gas requirements  1,755 MW out of 7,550 MW assumed Gas delivery constraints intensify by Winter 2005 –Shortfall in gas requirements  3,226 MW out of 11,500 MW assumed Theoretical mitigation potential thru back-up fuel: Winter 2003 - 71 gas-fired units totaling 16,000 MW - 51 dual fueled totaling 9,250 MW Winter 2005 - 75 gas-fired units totaling 18,650 MW - 54 dual fueled totaling 11,500 MW Gas Study

18. 18 RTEP Material on this page is consider Non-Internet Public (NIP) You would like a copy of this slide, please contact: Public Reference Room Telephone: 202-502-8371 Toll-free 1-866-208-3676 Email: public.referenceroom@ferc.govpublic.referenceroom@ferc.gov

19. NY-NE - 1400 w/o Cross Sound Cable SEMA - 1000 Norwalk-Stamford - 1100 Surowiec South - 1150 ME-NH -1400 North-South - 2700 Boston - 3600 SEMA/RI - 1600 NB Orrington South - 1050 NB-NE - 700 HQ Highgate - 225 Phase II - 1500 CSC -330 S-ME Load 575 1493 MW ME Load 1156 1093 MW BHE Load 376 874 MW SEMA Load 2329 3346 MW RI Load 2058 5419 MW W-MA Load 2041 3654 MW CMA/NEMA Load 1548 243 MW Peak Load and Installed Capacity MW by Area - 2006 VT Load 1353 879 MW NY NH Load 1914 3590 MW BOSTON Load 5257 3984 MW CT Load 3319 4359 MW SWCT Load 2662 2112 MW NOR Load 1129 463 MW Under Construction Other Studies Required RTEP Load Capacity KEY: Connecticut - 2500 Regional Transmission Expansion Plan Sub-area Priority Studies Required South West CT - 1700 East-West - 2150 RTEP

20. 20 Transmission Alternatives Various scenarios upgrading 115 kV lines from Frost Bridge, Southington and East Shore 115 kV Plan –Upgrade Devon to Norwalk 115 kV, Circuit 1 –Upgrade Devon to Norwalk 115 kV Circuit 2 –Upgrade Peaceable to Norwalk 115 kV –Build new Devon to Norwalk 115 kV –Build new Pequonnock to Norwalk 115 kV –Reconfigure Norwalk - Norwalk Harbor - Glenbrook 115 kV System Case 2 with Plumtree 115 kV Phase Angle Regulator Case 3 with with Beseck to Devon 345 kV 230 kV Loop: Plumtree - Norwalk - Beseck SW Connecticut

21. Long Mountain Frost Bridge Southington Beseck Junction Devon Pequonnock Norwalk Plumtree Proposed ‘345 kV Loop’ 1-Line NOR-STAM SWCT 115 kV 345 kV Proposed 345 kV Interface Key: 7 SW Connecticut

22. 22 Recommended Solution: 345-kV Loop Plumtree - Norwalk - Pequonnock - Devon - Beseck 345kV –2005 / 2006 in-service date; $500-$600 million –~100 miles - mostly on existing right-of-way –Includes associated 115kV improvements Meets study objectives: –Formulate long-term transmission solution for SW Connecticut that: Satisfies reliability criteria Eliminates operating difficulties Eliminates first contingency (including double circuit) overloads Eliminates threat of voltage collapse –Mitigates congestion by increasing SW CT and Norwalk-Stamford transfer limits SW Connecticut

23. 23 Improvement Associated With Recommended Solution Preliminary planning transfer limits –SWCT: > 2,900 MW (up from 1,700) –Norwalk-Stamford: > 1,300 MW (up from 1,100) –May eliminate the need for the Norwalk-Stamford interface definition Construction sequencing –NU has proposed a phased approach –ISO is currently investigating impacts SW Connecticut

24. 24 Other Associated Work Add new 345kV Substations at Plumtree, Norwalk, Pequonnock, Devon, & Beseck Junction Add new 345kV loop from Plumtree to Beseck Junction Add (2) 3-150MVA auto transformers at Norwalk, (1) at Pequonnock, and (1) at Devon Add (1) 3-200 MVA auto transformers at Pequonnock to shift Bridgeport Energy output to 345kV Rearrange / add to 115kV between Norwalk, Norwalk Harbor and Glenbrook Establish new 115kV substation adjacent to Devon (East Devon) Other 115kV work a/w new 345kV structures SW Connecticut