Microgrids and the Macrogrid

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Microgrids and the Macrogrid

• Presentation to the
• California Public Utilities Commission
• 20 February 2001
• by
• Abbas Akhil, Chris Marnay, Bob Lasseter
• Sandia National Laboratory, Berkeley Lab, and
  University of Wisconsin, Madison
• Consortium for Electric Reliability Technology
  Solutions
• Other Members of CERTS Distributed Energy
  Resources Group
• Bob Yinger - SCE, Jeff Dagle - PNNL, John Kueck -
  ORNL

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Outline

• INTRODUCTION TO CERTS - Abbas
• THE EMERGING MICROGRID PARADIGM - Chris
• DER TECHNOLOGY AND THE MICROGRID - Bob
• CONCLUSION - Bob
• QUESTIONS - all

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CERTS Mission Statement
CERTS Formation
Formed in 1998 as an Industry, DOE Labs and
Universities consortium

• To research, develop, and disseminate new
  methods, tools, and technologies to protect and
  enhance the reliability of the U.S. electric
  power system under the emerging competitive
  electricity market structure

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Research Performers
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Core Research Areas
Real-Time Grid Reliability Management
Reliability Technology Issues and Needs
Assessment

• Reliability and Markets

Distributed Energy Resources Integration
Addresses recommendations made by Secretary of
Energy Advisory Board (SEAB) Task Force on
Electric System Reliability
6
CERTS Road Map
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CERTS Industry Advisory Board

• VIKRAM S. BUDHRAJA - Chair
• President
• Electric Power Group
• MICHEHL R. GENT
• President
• North American Electric Reliability Council
• TERRY M. WINTER
• Chief Executive Officer
• California Independent System Operator
• PHILLIP G. HARRIS
• President and CEO
• PJM Interconnection, L.L.C.
• BRUCE A. RENZ
• former VP Energy Delivery Support
• American Electric Power
• Chair, AEIC Electric Reliability Committee
• EPRI Research Advisory Council

• CHARLES B. CURTIS
• Executive Vice President
• United Nations Foundation
• RICK A. BOWEN
• Executive Vice President
• Dynegy
• PAUL BARBER
• Sr. Vice President, Transmission Engrg.
• Citizens Power
• DALE T. BRADSHAW
• Senior Mgr., Power Delivery Technology
• Tennessee Valley Authority
• JOHN D. WILEY
• Provost Vice Chancellor, Academic
• University of Wisconsin

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Funding
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DOE CERTS Relationship
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The DOE DER Program Goals

• Near Term (Year 2005)
• Develop the next generation distributed energy
  technologies and address institutional/regulatory
  barriers
• Mid Term (Year 2010)
• Reduce the costs and emissions and increase
  efficiency and reliability of distributed
  technologies to achieve 20 of new capacity
  additions
• Long Term (Year 2020)
• Make the nations electric system the cleanest,
  most efficient, reliable and affordable in the
  world by maximizing the use of distributed energy
  resources

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Program Differences

• DOE DER Program sets national policy, goals
• Technology improvements Advanced microturbines,
  gas-fired engines
• Strong emphasis on combined heat and power
• Focus on reducing institutional and regulatory
  barriers
• CERTS DER activity focuses on DG systems issues
• Examines DG from transmission reliability
  perspective
• Effects of large penetration of DG into the grid
• Control, protection, role in the grid and
  competitive market

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Framing the Issues

• DOE DER Program goal
• 20 of new generation capacity additions through
  distributed generation by year 2010
• 26.5 GW of DG
• If small DG ( lt100 kW) captures 25 of the 26.5
  GW goal, then -
• 100,000 small DG sources could populate
  the grid

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Meeting Future Electricity Demand

• according to the Annual Energy Outlook 2001
• to 2020 U.S. electricity demand
• will grow at only 1.8/a (GDP at 3.0)
• but with retirements, thats almost 400 GW new
  capacity
• thats 92 natural gas fired, tripling NG use for
  power
• roughly equivalent to 1000 new generating
  stations plus associated transmission and
  distribution
  (an investment of 400 billion)
• NG prices increase at only 2/a real
• electricity prices fall at 0.5/a real
• share of electricity passing through high voltage
  grid unchanged

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Limits of Current Power System

• other restrictions on power system expansion
• siting, environmental, right-of-way, etc.
• efficiency limits (carbon, CHP/cogeneration,
  losses)
• centralized power system planning
• heterogeneous power quality requirements
• extreme customer requirements
• high cost of reliability?
• volatile bulk power markets
• economic drive to operate power system closer to
  limits
• can the traditional power system deliver digital
  power?

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Customer Driven Development

• apply emerging technologies to self generate
• meet heterogeneous customer requirements locally
• control reliability and quality close to end-use
• optimize meshed grid reliability for bulk
  transactions
• operate connected or disconnected to the grid
• make decisions about power system expansion
  operation
• group sources and loads
• optimize over compatible electrical and heat
  requirements
• power system of relatively weakly interconnected
  microgrids?

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A microgrid is ...

• designed, built, and controlled by customers
  based on internal requirements subject to the
  technical, economic, and regulatory opportunities
  and constraints faced.
• a cluster of small (e.g. lt 500 kW) sources,
  storage systems, and loads which presents itself
  to the grid as a legitimate entity, i.e. as a
  good citizen
• interconnected with the familiar wider power
  system, or macrogrid, but can island from it

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Customer DER Adoption

• goal is to anticipate the microgrid technical
  problems that must be solved
• forecast the attractive technologies and
  configurations
• customer decision is akin to utility planning
• local constraints on development critical - GIS
• microgrids unlikely to disconnect entirely
• DER adoption can/will be shaped by tariff policy

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DER Adoption by a Typical Office Building
on-site installed capacity
economic environment scenarios
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Key DG Technology

• Appliance like DG
• 100 kW 120 - 480 V
• Microturbine
• Photovoltaic
• Automotive Fuel Cell

• Substation DG
• 1-10 MW 2.2 kV up
• Combustion Turbines
• Reciprocating Engines
• Fuel Cells
• Hybrids

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Generation Efficiencies
1 MW
70

CHP
Hybrid Fuel cell
With CHP
60
CCTG
50
Fuel Cell
Micro Turbine
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GasTurbine
Reciprocating Engines
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Old steam
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10kW 100kW 1 MW
10MW 100MW 1000MW
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Reciprocating Gen Sets

• Diesel gen sets generally will be your best
  choice when
• Low installed cost (/kW)..
• Gas fuel is unavailable or expensive.
• Gas gen sets generally will be your best choice
  when
• Air emissions regulations are a concern.
• A reliable gas supply is available and
  affordable.

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Caterpillars Gen Sets

• In the last 60 days, Caterpillar installed 200MW
  of rental power throughout the West Coast U.S.
• During 2000, they sold nearly 20 gigawatts --

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Hybrid Fuel Cells/Microturbine

• Commercial Scale Plan
• Demonstration
• DOE
• Technology Program
• 250kW
• 1.3MW
• 2.5MW
• Electricity Efficient ( gt70)

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The New Paradigm

• Distributed generation. Small-scale power
  systems, installed on multiple commercial and
  industrial customers' sites, can function as a
  "virtual power plant" under utility control.
• Utilities can dispatch these distributed systems
  to enhance local grid stability, meet peak
  demands, capitalize on favorable market prices,
  and more.

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Application of Distributed Generation New
Paradigm

• KEY ISSUES
• Ratings gt 1MW
• Utility Voltages 2.2 - 66 kV
• Dispatchable
• Can Participate in Markets

• GENERATOR TYPE
• Combustion Turbines
• Fuel Cells
• Reciprocating Engines
• Hybrids

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Key DG Technology

• Appliance like DG
• 100 kW 120 - 480 V
• Microturbine
• Photovoltaic
• Automotive Fuel Cell

• Substation DG
• 1-10 MW 2.2 kV up
• Combustion Turbines
• Reciprocating Engines
• Fuel Cells
• Hybrids

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30-75 kW Micro turbine

• Installed at 700/kW (target is 350/kW)
• Efficiency 30
• Air foil bearings
• Operation speed 60,000-100,000 RPMs

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Microturbine Basics
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200kW Phosphoric Acid Fuel Cell

• The power plant in Santa Clara is rated at 1.8 MW
  AC net
• It contains more than 4,000 cells

2000-3000/kW
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Fuel Cell System
CO2
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On Site Generation

• NOx
• .00115
• .00124
• .000015
• .0005
• .00
• .010

• lb/kWh
• Microturbine
• C Turbine
• PEM Fuel Cells
• Hybrid FC/MT
• Roof top PV
• DualFuel Engine

• CO2
• 1.188
• 1.145
• 0.95
• 0.5
• .00
• 1.20

Air Pollution Emission Impacts Associated with
Economic Market Potential of DG in California,
June 2000
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Key Factors Impacting Application of Small
Distributed Generation

• KEY ISSUES
• Uses Power Electronics
• Ratings small 100kW
• Customer Voltages 120 - 480 V
• Dispatchable Very Complex
• Difficult to Participate in Markets due to small
  size
• Connection Cost High

• GENERATOR TYPE
• (appliance like)
• Microturbine
• Automotive Fuel Cell
• Photovoltaic

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Achieving the 100,000 units

• Rethink the paradigm
• System approach to DER
• Enable small-size DER to be a citizen of the grid
• Promote multiple unit installations
• Enable appliance type plug-and-play functionality
• Enable market participation

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MicroGrid Paradigm

• MicroGrid concept assumes a cluster of loads,
  micro-sources and storage operating as a single
  system to
• Presented to the grid as a single controllable
  unit (impacts system reliability fits new
  paradigm)
• Meets customers needs (such as local reliability
  or power quality)

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MicroGrid Paradigm

• Dispatchable load
• Responds to real-time pricing
• Simple protection

Utility

• Local voltage control
• UPS functions
• Local redundancy
• Digital power
• Loss reduction
• Use of waste heat

Customer
Loads, micro-sources storage
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Islanded Factory Micro Grid
Non-critical Loads
13.8 kV
480V
8
480V
22
16
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Critical Loads
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Frequency Droop
w
P
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Island Operation
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Conclusion 100,000 units

• Key The MicroGrid (An aggregation of
  micro-sources, loads and storage)
• Presents itself as a single operating entity to
  the grid
• Customer centered Key value added point
• Can participate in markets (load management)
• Recognizes combined heat and power applications
• No centralized fast control
• Visualizes an appliance model Plug Play
  model