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Microgrid – A Smart Grid Alternative Service Delivery Model?Thomas Bialek, PhD, PE Chief Engineer

SAME Luncheon – May 12, 2010

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The Utility World Today

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The Utility World 2015 +

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The Utility World Tomorrow

SDG&E Borrego Springs Microgrid Project

Project Description:

In cooperation with the US Department of Energy and the California Energy Commission, SDG&E and 10 public and private sector partners will develop a “microgrid” project - a small version of its electric grid which takes advantage of local distributed energy resources and state-of-the-art controls to enhance grid operations – to achieve a >15% reduction in feeder peak load and improve system reliability.

Current Status:

•Site Selection complete – Borrego Springs•Finalizing system requirements and high level design•Developing customer communication plan•Collaborating with environmental agencies to satisfy permitting requirements

Energy

Storage

Micro turbine

Rooftop PV Solar

Utility-scale Energy Storage

Distributed GenerationHome Energy System

Ground PV Solar Array

PHEVs

Switches &

Power

Electronics

National Energy Technology Laboratory

Distributed Energy ResourcesUtility-scale Energy StorageRooftop PV SolarMicro-turbinesBuilding Energy StorageCommunity Energy StorageDistributed GenerationHome Energy SystemPHEVsGround PV Solar Array

Grid ResourcesCapacitor Banks

Voltage RegulatorsAutomated Switches

Power ElectronicsCommunications

InformationElectricity PricingDER statusDemand Response ProgramsNetwork statusCommunity ObjectivesLoad and Resource Profiles

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Microgrid Selected Project Site: Borrego Substation

Borrego offers SDG&E an opportunity to be the leader in the microgrid area, with the possibility of being able to island an entire substation with peak load of over 13 MW.

Key Characteristics:

Strengths:• No residences nearby, plenty of land

• More Existing Solar Customers

• Large Reliability Improvements Possible

• Possibility of ‘Islanding’ Entire Community

• Great learning environment

• Extendable to service territory

Challenges:• Remote Area

• Challenging Communications Environment

• New Fencing Required

• Requires Accelerating schedule for

Condition Based Maintenance and AMI Deployment

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Project Architecture: Context Level Architecture

MicroGrid Context Level ArchitectureEndpoints Last Mile Network Backhaul Network

SE

u E

SB

/EI

Outage Management/Distribution Management(OMS/DMS)

Itron MDMS

Customer Information System (CISCO)

Itron AMI Meter

Data Collection Backoffice Systems

SCADA

Openway Collection Engine

Utility DG (2x 1.8MW)- Diesel Generator

Utility Storage (~1 MW)- 3.3kw Battery

- TBD

VAr Devices (~1 MW)- VAr Compensator

Feeder Automation (FAST)- SCADA Automated Switches

- SCADA Controllers on3 existing capacitors

RF Mesh

HAN Device (ADM)

- Thermostat- Water Heater- Pool Pump

Customer Storage(Gridpoint Connect)

Solar(Gridpoint Connect)

HAN

HAN

HAN

GIS

Shared with CBM

DRCA

CRM SAP

DERMS

IBM

IBM

IBM

IBM

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Issues and Challenges

• Coordination of Efforts Across Departments and with Subcontractors

• Integration of Utility and Customer Distribution Energy Resources

• Distribution Automation

• Asset Management

• Security – Cyber & Physical

• Establishing Secure Communications Network

• Development of Appropriate Systems and Related IT Architecture

• Customer Participation in DG and Demand Response Programs

• Regulatory and Tariff Impacts

• Integration of New Market Participants

• Cross-jurisdictional Issues