Microgrids: A Growing
Trend in the Power Industry
Dr. Brian Hirsch
Senior Project Leader – Alaska
National Renewable Energy Laboratory
USAEE Conference - Anchorage, AK
July 29, 2013
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.
Microgrids – Alaska Context
• Energy is EXPENSIVE: up to $10/gallon & $1/kWh; highly variable
throughout state
• Very limited economies of scale within communities, BUT ~200
communities + remote industrial operations
• Remote, challenging logistics – limited transportation, communication,
infrastructure, human and physical capital, etc.
• Heat is not optional, and consumes more primary energy than electricity
• Some relative success stories in terms of high penetration wind-diesel
hybrids, e.g., Kokhanok, Kongiganak, Kwigillingok, Kodiak
Icing in Nome
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Village of Ugashik
Hybrid Performance Monitoring Project
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Working with ACEP at UAF, AEA
Monitoring performance of wind-diesel-battery
hybrid system to determine relative
contribution of various RE inputs and diesel
savings for system optimization
Results replicable for other projects in region
and beyond
Very windy site (class 5), but PV performed as
well as wind on kWh/kW installed basis, and
better on a $/kW installed basis with current
pricing
14%
51%
34%
Ugashik Hybrid Power: Wind, Solar, Diesel, Battery
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Microgrids in Broader Context
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What is a microgrid?
o
“group of interconnected loads and distributed
energy resources that acts as a single
controllable entity with respect to the grid. It
can operate in both grid-connected and
island-mode” [Office of Electricity, DOE Microgrid
Workshop Report, 2011 San Diego, CA]
o
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“Best hope for developing world”, according to
UN
What is energy security? US Navy:
Source: IEEE 1547.4
o
“having assured access to reliable and sustainable supplies of energy and the ability to protect and
deliver sufficient energy to meet operational needs”
o
2008 Defense Science Board Task Force on DoD Energy Strategy described vulnerability of the
nation’s electric power grid
o
The number of large blackouts at a national level is growing in number and severity
Miramar had an eight hour outage in September 2011
o
o
o
o
Training missions were canceled and planes grounded
Most personnel (both military and civilian) were sent home
Marines needed to man electric gates, traffic lights and other facilities
Food spoilage in mess halls and commercial outlets
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Background
MCAS Miramar
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Outside San Diego, CA
Primarily flight training and operations
Peak loads are summer afternoons
o
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Track record of successful EE and RE projects
Critical loads are Flight-Line and supporting facilities
o
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14 MW peak, 7 MW avg, 5 MW min
6 MW max, 3.5 MW avg, 2.5 MW min
Electrical configuration allows for centralized control point
Microgrid Design Criteria
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Operate for at least two weeks
Power critical loads upon loss of utility grid
Incorporate as much renewable energy as feasible
Phased approach to include entire base in the microgrid
Redundant fuel sources important to enhance reliability
Demonstration project for the Marine Corps and DoD
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Summary
• NREL completed NZEI assessment in 12/2010
• MCAS Miramar energy projects to date:
o
o
o
o
o
o
Numerous energy efficiency projects
1 MW of solar PV plus solar parking lot and
street lights
Solar thermal pool heating
3 MW landfill gas PPA
ESTCP energy storage project
Currently approximately 50% renewably
powered
• Miramar received funding to perform
microgrid assessment in 03/2011
o
o
NREL worked with Miramar to complete a
conceptual design plan report completed on
09/2012
Awaiting ECIP funding request for microgrid
implementation
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NREL’s Approach to Microgrid Design
• Continuously Optimized Reliable Energy (CORE)
Microgrids
• Differentiating Characteristics:
– Integrates into 24/7 operations
– Can optimize on economics or surety
– Focuses on fuel diversity
– Expands/contracts to provide energy for all
load coverage spheres
– Phased approach can allow for gradual
addition of components over time
 Load prioritization and migration with added
generation
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CORE Microgrid Design Process
Step 1:Evaluation of
Existing Reports
NZEI Assessment
Existing
Generation
Step 2:
Data Gathering
Step 3:
Design Analysis
Grid Infrastructure
Detailed Electrical
Model
Modeling &Studies:
•Power Flow
•Dynamic Stability
•Short-Circuit
Generator
Specifications
Controls
Load Profiles
Existing Energy
Management System
Energy Surety Plan
Financial Analysis
CORE Microgrid Design Process is replicable
o
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Inform
RFP/Cost
Estimating
Selection of
Integrator
Construction
Communication/
Cyber security
Grid
Operations/Valuing
Energy Security
•
Step 4:Installation
and Monitoring
Currently being applied at the USAFA
Identifies potential solutions for acceptable levels of risk and economic value streams
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Independent
Verification
& Validation
Modeling Overview
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Modeling is needed because Microgrids present unique
design challenges
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o
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What do you Model:
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Electrical distribution system, generation equipment, loads, and
control system response
Use the model to simulate operating scenarios and predict
performance
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Self regulation for voltage and frequency
Advanced controls and protection schemes
Fossil fuel and alternative energy generation resources
Need to analyze start up sequence
Microgrid start up, feeder loss, faults, different generation options
Modeling conclusions can be used to inform
o
Generation type/sizes, supervisory controls, operating procedures
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Modeling Summary and Recommendations
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A minimum of 4 MW of diesel is recommended
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As expected, an all-diesel solution would work
The 4 MW diesel, combined with 2 MW gas may work
o
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This is needed for adequate load pick-up
Transient voltage/frequency excursions would be larger, and would
likely require subdivision of feeders and/or auxiliary assets for
transient support
It is unlikely that an all-gas solution could work without
energy storage and/or load control due to large load steps
The best solution for cost and performance may be a
hybrid system, with PV, diesel, LFG, storage, and natural
gas
o
Optimization needs to be done as part of formal design
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Financial Analysis
• Capital costs were estimated for a variety of
scenarios
o Selected design ~$25 M
o Excludes costs associated with cyber security certification
• Revenue streams from peak shaving, demand
response, and offsetting grid purchases
o Offsetting grid has most value but has operations and air
permitting challenges
o SDG&E demand response program is established revenue
stream and increasing need for the utility
• Operation and maintenance costs still need to be
estimated
o Will vary substantially based on selected O&M scenario
• Most scenarios don’t have a positive NPV
o Still a better value than a system that can only be used for
backup power (diesel)
o Energy security value
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Lessons Learned
• CORE microgrid design process identified a workable solution to inform
an RFP with performance specifications and verification and validation
options
An acceptable level of risk is needed to determine the appropriate costs for a
given level of increased reliability
o Continuous operation decisions related to revenue streams impact the design
o
– Single fuel generators are cheaper and more functional option than dual fuel options
• Microgrid operations decisions are critical and heavily influence design
o
Operating and maintenance responsibility decisions are complex and may
need to be determined as the project evolves
• Cyber security certification will be a challenge
• Demonstration microgrid projects are needed at DoD sites:
Further develop the technology, identify applications, and determine total
costs
o Commercially available technologies are out there
o
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Microgrid Market Is Global Phenomenon
Microgrid Capacity by Region, World Markets: 2Q 2013
Rest of World,
393.68
Asia Pacific, 390.24
Europe, 508.13
North America,
2,473.54
(MW)
(Source: Navigant Research)
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Five Primary Market Segments
Microgrid Capacity by Segment, World Markets: 2Q 2013
Commercial/
Industrial, 439.29
Remote Systems,
754.52
Community/ Utility,
928.80
Military, 614.27
Institutional/
Campus, 1,028.71
(MW)
Source: Navigant Research
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Microgrid Capacity Scenarios
Microgrid Capacity by Forecast Scenario, World Markets: 2013-2020
14,000
Base Scenario
12,000
Average Scenario
Aggressive Scenario
(MW)
10,000
8,000
6,000
4,000
2,000
2013
2014
2015
2016
2017
2018
2019
Source: Navigant Research
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2020
Microgrid Capacity: North America is
Global Leader Now, and Projected 2020
• Microgrid Capacity, Average Scenario, World Markets: 2013-2020
10,000
9,000
North America
Europe
8,000
Asia Pacific
(MW)
7,000
Rest of World
6,000
5,000
4,000
3,000
2,000
1,000
2013
2014
2015
2016
2017
2018
2019
2020
Source: Navigant Research
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Microgrids, but NOT micro dollars
• Microgrid Revenue by Forecast Scenario, World Markets: 2013-2020
$70,000
Base Scenario
Average Scenario
$60,000
Aggressive Scenario
($ Millions)
$50,000
$40,000
$30,000
$20,000
$10,000
$2013
2014
2015
2016
2017
2018
2019
2020
Source: Navigant Research
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Large Obstacles Remain
• Policies: No integrated approach, in part because of
diversity of applications, resources, settings – No
“one size fits all”
• Costs: wholesale power is still cheap; energy
storage and niche/small generation is still expensive
• Technology: Advanced controls, smart grid, system
integration still evolving
• Value Propositions: All energy is not created equal
(surety, reliability, power quality), but is often
priced the same
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Examples of campus microgrids
• BC-Hydro/British Columbia Institute of
Technology (BCIT) microgrid:
http://www.bcit.ca/microgrid/
• University California San Diego campus:
http://ssi.ucsd.edu/
• Illinois Institute of Technology:
http://www.iit.edu/perfect_power/
Thank You and Questions?
[email protected] or 907-299-0268
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