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Contract No. DE-AC36-08GO28308

Test of a 250 kVA BatteryInverter System Micro-Grid

Cooperative Research and Development 

Final Report

CRADA Number: CRD-11-460

NREL Technical Contacts: William Kramer, 

Greg Martin, and Blake Lundstrom

CRADA Report

NREL/TP-7A10-58889

December 2013
NOTICE

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Cover Photos: (left to right) photo by Pat Corkery, NREL 16416, photo from SunEdison, NREL 17423, photo by Pat Corkery, NREL 

16560, photo by Dennis Schroeder, NREL 17613, photo by Dean Armstrong, NREL 17436, photo by Pat Corkery, NREL 17721.

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1

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Cooperative Research and Development Final Report

In accordance with Requirements set forth in Article XI.A(3) of the CRADA document, this document is 

the final CRADA report, including a list of Subject Inventions, to be forwarded to the Office of Science 

and Technical Information as part of the commitment to the public to demonstrate results of federally 

funded research.

CRADA Number: CRD-11-460

CRADA Title: Test of a 250 kVA Battery-Inverter System Micro-grid

Parties to the Agreement: Portland General Electric

Joint Work Statement Funding Table showing DOE Commitment:

Estimated Costs NREL Shared Resources

Year 1 $ 00.00

Year 2 $ 00.00

Year 3 $ 00.00

TOTALS $ 00.00

Abstract of CRADA Work:

Portland General Electric (PGE) is installing a 5-megawatt (MW) lithium-ion-based battery-inverter 

system (BIS) in Salem, Oregon, as part of the Pacific Northwest Smart Grid Demonstration Project. 

NREL will assist PGE in testing a 250-kilovolt-ampere (kVA) portion of the BIS in order to verify correct 

operation and minimize risk to subsequent demonstrations. In this project NREL will provide technical 

support for the 250-kVA test and will work with PGE to write a test plan and evaluate the system in the 

lab before deployment in the field.

Summary of Research Results:

The purpose of this research was to integrate and evaluate a 250-kVA lithium-ion BIS prior to 

deployment in the field at a larger scale (5 megavolt ampere [MVA]). The BIS was an integrated system 

of devices, each of which was built by a different PGE partner. Thus, much of this project was performing 

the integration of these key devices and ensuring that the system would perform as intended. NREL 

researchers utilized key infrastructure—a 480- volts alternating current electrical bus system, grid 

simulators, load banks, a diesel generator with an onboard control system, an NREL-designed fault 

simulation box, and oscilloscopes and meters—of NREL’s Distributed Energy Resources Test Facility to

simulate the grid-connected and local microgrid (islanded) conditions that the BIS would experience 

when connected to a substation in PGE’s electrical system. This effort involved three phases of testing:

• Performance testing – Verify that the battery, inverter, and PGE control system function as intended

and work together as an integrated system
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This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

• Transition testing – Verify correct operation of the BIS and controls in changing between operating 

states (e.g., on-grid vs. off-grid)

• Fault simulation testing – Evaluate the response of the BIS and controls in the event of a fault while 

operating on-grid and islanded.

This project was successful in that many improvements were identified and corrected at NREL prior to 

trying to deploy the BIS at a much larger scale in the field. Also, the performance of the integrated BIS 

was evaluated and used to help inform the design and operation of the larger 5 MVA system. NREL has 

the capability of evaluating integrated energy systems up to the megawatt scale at its DERTF and Energy 

Systems Integration Facility.

Subject Inventions Listing:

None

Report Date:

Nov. 4, 2013

Responsible Technical Contact at Alliance/NREL:

William Kramer (no longer at NREL)/Greg Martin/Blake Lundstrom

This document contains NO confidential, protectable, or proprietary information.