Resilient and Renewable Microgrids · o 7 MW max, 4 MW avg, 2.5 MW min o 4.5 MW of existing renewable energy • Requirement to operate for at least two weeks in islanded mode and

Rhode Island Convention Center • Providence, Rhode Island

Resilient and Renewable Microgrids

Session: Planning Large and Small Scale Microgrids and Smart Grids

Sam Booth National Renewable Energy Laboratory

August 10th, 2016

Energy Exchange: Federal Sustainability for the Next Decade

This presentation reviews several key aspects of microgrid planning and design along with examples projects including:

– Requirements determination and load analysis

– Generation analysis with an emphasis on renewable energy

– Microgrid modeling

– Operating requirements

– Lessons learned

2

Summary


National Renewable Energy Laboratory (NREL) Overview

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Supports DoD’s complementary missions related to energy use.

Dedicated to Advancing Energy Efficiency, Renewable Energy and Energy Systems Integration. • Owned by the Department of Energy • Leading clean-energy innovation for 34

years • ~2500 employees with world-class facilities • More than 350 active partnerships • Campus is a living model of sustainable

energy


• What kind of microgrid, building, campus, or utility ?

• What type and duration of outage do you need to survive?

• What other things do want your microgrid to priortize e.g. economic savings ?

• Start by identifying and classifying loads o Sheddable, essential

critical?

• Initially need to determine o Min, average, and max

loads o Load profile o Types of loads

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Microgrid Requirement and Load Analysis

NREL CORE Microgrid Design Process


Miramar Example: Requirements Determination

• Power critical loads on Flight-Line and supporting facilities in the event of a grid outage with potential for future expansion

o 7 MW max, 4 MW avg, 2.5 MW min

o 4.5 MW of existing renewable energy

• Requirement to operate for at least two weeks in islanded mode and use redundant/on-site fuel sources to enhance resiliency

• Project Goals:

o Energy Resilience

o Maximize renewable energy and use of existing assets

o Revenue from grid tied operations and grid support

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• Existing generations sources • New generation options • Match between generation and load • For renewable energy analyze resource,

incentives, technologies, permitting, etc. • Benefits of renewables

o Extend duration of outage o Potentially limitless power supply for

continued operation of selected loads o Improve economics by providing grid

connected value

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Microgrid Generation Analysis

0%

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Pro

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Length of Outage [Days]

Base Case +2.0 MW PV,500 kWhBatt

Base Case +625 kW PV,175 kWhBatt

Dispatch Strategy

Grid Outage

Battery Charging


Renewable Generation Technologies

Biomass Heat/Power

Concentrating Solar Power

Wind Power Landfill Gas Photovoltaics

Geothermal

Hydro Fuel Cells

Others:

- Biofuels (e.g. biodiesel) for generators

- Waste to energy

- Marine hydrokinetic

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Energy Exchange: Federal Sustainability for the Next Decade 8

Renewable Energy and Storage Cost Reduction Trends


Rule of Thumb for RE in Hybrid Systems

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Example Project: MCAS Miramar ESTCP

• Smaller Microgrid demonstration project at Miramar’s Public Works building; successfully islanded December 2015

• Raytheon controller, 200 kW PV, 250 kWh Primus Power flow battery, building loads

• Battery supported the islanded grid with high PV penetration (80%); automated inverter curtailment function used; significant clouding events

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Energy Storage & Inverters

Energy storage coupled with bi-directional inverters permit:

Smoothing of PV generation

Dispatchable power

Peak load reduction/shifting

Voltage support

Frequency support

More responsive than conventional generation

Can provide excellent power quality

Inverter technology has advanced significantly in recent years

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60.14

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Utility-Friendly Features of Modern Inverters

• VAR Support for Grid o Can adjust load power factor (leading or lagging)

• Low & High Voltage/Frequency Ride Through Capabilities o Can stay on-line during grid voltage & frequency disturbances

• Communication Capabilities o Requires infrastructure (fiber optic, copper, radio, etc.)

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L3 (

A)

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• Curtailment of Inverter Power Level o Disable inverter o Discrete step increase

or decrease

• Ramp Rate Control o Reduces sudden load

changes

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Example Project: PMRF Navy Tech Demonstration

• Pacific Missile Range Facility (PMRF) located on western shores of Kauai, Hawaii - unusual daily load profile due to mission activities

• Energy Management System project with Honeywell (2013) enabled connection of stranded PV without compromise to installation’s power quality, and prevented backfeed to utility

o Energy Storage - lithium iron magnesium phosphate batteries

o Monitoring and Control System

• Awarded FY16 ESTCP project for expansion

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• Modeling is necessary because of unique design challenges o Self regulation for voltage and frequency o Advanced controls and protection schemes o Fossil fuel and alternative energy generation

resources

• What do you Model: o Electrical distribution system, generation equipment, loads,

and controls o Microgrid start up, feeder loss, faults, different generation

options

• Power and/or controller hardware in the loop testing is also recommended for risk reduction

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Modeling and Testing Overview

Speed Controller

(Governor)Σ Fuel Actuator

Engine

Air

System

Power

System

Turbo

Charger

Frequency

Speed

Bias

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Filter

Diesel

Injection

Gas

Injection

Transient model comparing respond of diesel and natural gas engines

Hardware in the loop testing of Raytheon Microgrid Controller at NREL’s ESIF


Example Project: Alcatraz Island Microgrid

PV/Battery/Diesel Hybrid

System

Agency: NPS

Location: Alcatraz Island, California

DOE FEMP Assistance

resource and load monitoring (14 months);

feasibility study;

financing and contracting assistance;

design charrette;

design review;

construction RFI’s;

commissioning assistance;

performance evaluation and recommendations.

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• DHS

• Park service

• Verizon

Other Off Grid U.S. Project Examples

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General Considerations

• Skilled staff (typically engineers or electricians) are needed to operate a microgrid

• Specifics skill are dependent on the particular project, key considerations include safety, level of automation, control characteristics, and risk.

• Microgrids are not standard in the DoD and training is required

• Need simulated training environment

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Microgrid Operations

Miramar Example

• Operated and staffed in partnership with NAVFAC (Miramar’s utility) o From new microgrid operations center

• Grid Connected Mode – Awareness, efficiency, cost savings (~99% ) o Advanced Metering and real-time

monitoring

o Analytics, trends, and reports

o Corrective action on building equipment

o Execute demand response

o Load management/peak shaving

o Monitor renewable energy systems

• Islanded Mode – emergency situation or power outage (~0-1%) o Operate Microgrid

• Several weeks of training and computer simulation trainer for operators provided


• Capital costs are dependent on a number of factors o Extent of critical loads & electrical system o Infrastructure modifications required o New and existing generation requirements o Energy storage/spinning reserve requirements o Utility acceptance o Communications methods o Environmental regulations

• Revenue streams from grid connected operations are essential to have savings o Self generation o Demand response o Peak shaving o Ancillary services

• Energy security valuation conducted o Methodology to value non-energy savings attributed to energy security projects o Studied impact of an outage and developed a customer damage function o Analyzed utility reliability o Value = Cost of an outage x probability of an outage

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Microgrid Business Case

Business Case Value of Energy Security + Revenue Streams > Capital and O&M Costs of Microgrid


Miramar Installation Microgrid Summary

• Primarily flight training and operations

o Site: 14 MW peak, 5 MW min o Critical: 6 MW peak, 2.5 MW min

• 8 hour utility outage in 2011

o Flights grounded (mission halted), generators didn’t start, gate security issues, food spoiled, etc.

• CORE microgrid assessment completed in 2012

o Critical load analysis o Generation option analysis o Electrical systems modeling o Financial analysis and ECIP application

• Project awarded ~$20 M in ECIP construction funding

o New generation and microgrid operations center o Savings from from peak shaving and demand response o Challenges: RE integration, cyber security, and being first o NREL supported RFP development and reviews

• Project recently awarded and in design phase

o Will be largest, most renewable/advanced DoD microgrid o First at site wide scale with high levels of diverse

renewable energy and savings from grid connected operations

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Lessons Learned

Lessons Learned

• Renewable energy and sustainability don’t always mean resiliency

• Resiliency can mean different things to different people

• For DoD cyber security is a key challenge

• Success requires ongoing development support

• Motivated partners are the key differentiator

Possible NREL Microgrid Project Support

• Portfolio evaluation of microgrid business case across or at select sites

• Development of promising microgrid projects

• RFP development and bid reviews

• Joint technology development or demonstration programs

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Thank You! Sam Booth

303-275-4625 [email protected]

Documents

Resilient and Renewable Microgrids · o 7 MW max, 4 MW avg, 2.5 MW min o 4.5 MW of existing renewable energy • Requirement to operate for at least two weeks in islanded mode and