Smart Grid Projects NSTAR Larry Gelbien New England Restructuring RoundTable December 4, 2009

AGENDA Overview of Three Smart Grid Projects Questions Grid Self-Healing Project Urban Grid Monitoring and Renewables Integration Project AMR Based Dynamic Pricing Project Questions

Grid Self-Healing Project DOE ARRA Deployment Project

Automated Sectionalizing Unit Program Cumulative Number of Averted Sustained Customer Outages Due to ASU Operations: Through 10/31/09 Slide Updated November 9, 2009 4 4

Top Decile Reliability Restoration 2006 2007 2008 2005 YTD 2009 10.9 Avg. months between interruptions Avg. time to restore service 2006 2007 2008 2005 YTD 2009 10.9 12.4 9.8 16.1 11.8 Our successes reflect the robust Performance Management Process at NSTAR. We track, measure and report on several critical performance metrics each and every month. As you can see – our electric system reliability is outstanding and when we experience an outage - we’re able to restore power quickly. These performance results are in the top decile in our industry And these results have continued through September 2009, with reliability at 16 months between interruptions and restoration at about 78 minutes. 2006 2007 2008 2005 YTD 2009 77.5 69.5 76.6 94.4 78.2 5 5

Smart Grid – Distribution Automation Over 1,300 SCADA Switches with over 7,500 smart sensors installed through the service 40 to 60 new devices with 120 additional smart sensors annually 6 6

Smart Switch Equipment 7 7

“Self-Healing” Distribution Grid With State-of-the-Art Technology Electric delivery network using modern sensing, communications, and information processing based on digital technologies Microprocessor-based measurement and control using remote sensors Current, voltage, KVA, temperature Circuit self-healing implementation (Auto-Restoration): 900 circuits Supervisory controlled overhead and underground switches with voltage and current sensors: 220 switches Interoperability standards using PI interface SCADA interface to recloser control cabinet: 20 reclosers 8 8

Three Operational Modes Mode 1: “Supervisory” mode Leverages remote control of switches Operator controlled sequences Mode 2: “Operational Acknowledgement” mode Computer-simulated restoration sequences Operator validation and execution Mode 3: “Self-Healing” mode Computer-determined restoration sequences No human intervention 9

NSTAR Grid Improvement – Example of how ASUs work 10 10

Self-Healing Auto-Restoration 11 11

GWAC Interoperability Checklist for Project --Short discussion of how the approach to DA has changed to provide more interoperability and flexibility --RTU and radio vendors, etc. can be substituted if necessary. --A quick look at the GWAC Checklist document will be useful 12 12

DOE Funding Approved $20 million deployment project with 50% DOE funded NSTAR to fund 50% as capital project DOE grant agreement to be executed

Urban Grid Monitoring and Renewables Integration Enablers to Test Distributed Resource Integration 14

Project Objectives Improve visibility into secondary area network grid Deploy sensors on the underground secondary network methodology Refine methods suitable to scale broadly across urban areas nationwide Develop model to safely examine small inverter-based distributed resource integration Solar PV integration from downtown customers Potential for integration anywhere on the test grid Pave the way for other, inverter-based DER in the future Received DOE Smart Grid demonstration grant, pending DPU approval 15

Demonstration Grid Location (Shown in Red) 16 16

Functionality Deployed in “Layered” Approach Layers provide the data collection, monitoring, and analysis required for safely testing distributed resource integration 17 17

Metering and Analysis Distributed resource interconnection on secondary networks IEEE 1547 examined Approach submitted for comment at August 2009 IEEE meeting Additional metering capability kWh smart metering on customers with PV integration Enhanced feeder data metering including V & A phase info Customer PV interconnection Power flow monitored Remotely controlled to disconnect on unsafe condition Engineering analysis All sensor data to be collected at Collection Server Information forwarded to SCADA system and plant information system for Engineering, Operations, and Planning access 18

Project Topology View 19 19

Key Questions to be Answered What significant deployment and installation challenges were encountered? What is the percent of load from participating customers? From PV vs. other sources How effective was the mixed data collection methodology? What is the frequency of disconnect due to grid stability concerns? Will a higher percent of minor-node be effective in the future? How durable is the sensing equipment, especially minor-nodes? 20

AMR–Based Dynamic Pricing Project Pilot requirements Cover at least 2,750 customers (0.25 % of subscribers) Integrated two-way communications Smart meters Real-time measurements and communications Embedded automated load management Remote monitoring and operation of distribution system Time-of-use or hourly pricing Rate treatment of incremental program costs Minimum 5% load reduction (peak and average) Received DOE Smart Grid demonstration grant, pending DPU approval 21 21

Tendril Transport (gateway) Consumer Behavior: Provide Accurate Information to Make Informed Decisions Load Control Pricing Options Energy Efficiency (CFL, Load Control, Solar, DG, PHEV) broadband Tendril Insight (in-home display) Tendril Set-Point (thermostat) Tendril Transport (gateway) Tendril Volt (outlet) Tendril Mobile 22 22

Near Real-Time Information for Customers and Utilities Communication Options Least Cost Options Minimize Stranded Costs Mesh AMR/AMI over Customer’s Broadband Service Broadband over Power Line Cellular Placed here as this seemed a good point to discuss the wide range of communications options 23 23

QUESTIONS?