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C PER Center for Advanced Power

Engineering Research 2017 Summer Research Planning Workshop

Energy Storage Technologies and Application Roadmap

Presented By:

Johan Enslin Zucker Family Graduate Education Center (ZFGEC)

Clemson University Restoration Institute (CURI)

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Overview • Energy Storage – Global Growth Path

• Cost of Energy Storage

• Stacked Values and USE Cases

• Technology Capabilities

• Case Studies

– Tehachapi Energy Storage (SCE)

– Marshall Test Facility (Duke Energy)

• BESS Testing and Model Validation

• Roadmap Development with Value Chain

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• 2015 growth 240% & 2017 growth expected 200% • Annual U.S. energy storage market projected to reach

1.7 GW by 2020 – with a value of $2.5B1 • Energy storage for solar systems expected to be an $8 B

market in 20262 • Acquisitions and mergers e.g. Siemens & AES (Fluence) • Energy storage is a key enabler for renewables, T&D grid

optimization and generation efficiency

1 Source: GTM Research 2 Lux Research Inc. 3 DOE (Energy Storage Exchange)

Global Energy Storage Development

- 171.05 GW 1,267 Projects

U.S. Energy Storage Development

- 24.2 GW with 570 MW in Battery Storage

Energy Storage: High Growth – High Potential

US Deployment Forecast, 2012- 2022E (MW)

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Cost of Energy Storage

Source:- SolarPlaza

• Energy Storage is not cost effective in single USE cases • Stacked Values are crucial to make a cost effective

business case

Source: EPRI

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Stacked Value Streams

Comparison of Storage Cost Compared to Individual Grid Service Benefits - No single business case

Benefit Stacking as a Simple Sum - Clear business case

*EPRI Energy Storage Valuation Tool

Energy Storage Service provider Opportunity

Integrate all possible services

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Power-to-Power Use Cases

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Application Requirements

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Technology Capabilities

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Tehachapi Energy Storage – Case Study • The project is strategically located in the Tehachapi Wind Resource Area.

– 4.5 GW of developed wind power by 2016 – State procurement target of 1.325 GW of energy storage capacity by 2020 – (CPUC AB 2514)

• Wind farm related grid reliability issues – Most of older wind farms in area are Type 1 turbines – 380 MW installed wind capacity (310 MW operation) – Absorb around 100 MVAr reactive power from system – No Low-Voltage-Ride-Through (LVRT) and reactive power support capability – Non-compliant with FERC - LGIP – Wind curtailment during high wind generation

• 66 kV line reliability – N-1 contingencies require

> 60 MW wind curtailment on daily basis – Angular stability concern during line trip – Existing SVC (14 MVAr) not reliable – Limited reactive power support on system

Configuration of Tehachapi Energy Storage Project 8MW/4hr Battery and 20 MVAr for 4 sec. STATCOM

Project investment is $35 M ($ 55 M final budget with M&V) ROI > 13% due to stacked values on USE cases:

• Transient stability mitigation for the N-1 contingency • 50 MW wind curtailment mitigation • Hourly wind dispatch of 50 MW wind farms • Voltage and frequency regulation • Avoided cost NPV = $3.2M p.a.

Ref:- Castaneda, J; Enslin, JHR; Elizondo, D; Abed, N; Teleke, S: “Application of STATCOM with Energy Storage for Wind Farm Integration” New Orleans, LA, USA, IEEE PES T&D Conference & Expo, 19-22 April 2010.

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1 – Energy Time Shifting a) for system-level arbitrage b) for local operational constraint management c) based on forward-looking economic algorithm 2 – solar output PV smoothing and firming a) for local feeder voltage management b) solar-induced power swing mitigation 3 – active VAR / power factor management 4 – combined algorithms / optimization a) Combined Voltage Regulation, Energy time shifting and PV smoothing algorithms b) Use of distributed logic with economic, sub-station, forecasted and local input parameters

Battery container 750 kWh/250 kW Lithium Polymer Includes EMS.

Inverter/Controls Storage Management System (SMS) 1.25 MVA capacity/1.0 MVAR capacity

1.2 MW solar facility

1000 kVA transformer Steps up 480 V inverter output to 12.47 kV

Marshall Steam Station, Sherrills Ford, NC

System Attributes

Major system components: • 750 kWh / 250 kW system capacity • Kokam Superior Lithium Polymer Batteries • 1.25 MVA S&C Electric Company Inverter (SMS) • 1 MW PV solar test installation • Real-time control link to EPIC at UNCC

Interconnection: • Located on a 12.47 kV distribution circuit • Separate but adjacent medium-voltage interconnection from 1 MW solar facility • Located at the end of a distribution feeder

• Installed and in service July 2012

• Remote control and operation

• Battery and inverter independently sourced • Both vendors to Duke

• Located at the Marshall solar test site where multiple solar technologies are being field tested on a sealed coal-ash landfill • Develop and test new optimized control algorithms in cooperation with EPIC

Energy Storage – Stacked Value Algorithms

Applications Developed and Tested

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PhaseStation

Regulator

Line

Regulator 1

Line

Regulator 2

A 3 15 14

B 4 15 9

C 4 15 14

A 2 5 6

B 4 5 10

C 4 5 10

No Voltage

Support

(1/26/2015)

BESS Voltage

Support

(1/27/2015)

Tap Operations

250 kW 750 kWh

Station Regulator

Line Regulator 1

Line Regulator 2

Voltage Support Algorithm Field Testing Results Development of Stacked Value Proposition for Storage

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Battery

Saver Mode

Energy Arbitrage

(PLS)

PVCF

Accurate Prediction

of Feeder Peak Load

for Peak Load

Shaving

Charging Battery

during minimal

feeder load

Firmed PV

Station Output

PV Smoothing & Energy Time Shift Field Testing Results

Development of Stacked Value Proposition for Storage

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Expert Energy Management System

Cloud State Pattern Recognition and Optimization

The framework is as follows-

• Characterize Cloud Cover Days.

• Criteria is built to identify each defined day type.

• Optimization routine

• Weather forecasts to identify next day cloud state

• Identify day type and adopt optimal values

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Energy Storage Validation and Testing • Validate performance, efficiency, ancillary services.

• Demonstrate virtual inertia, primary and secondary frequency response.

1 MW, 510 kWh

Static Losses

Charge Discharge

Charge Discharge

Zoom in on low power levels

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Example of Roadmap Development • Need and USE Case Development • Technology Assessment • Economic and Incentive Assessment • Financial and Stack-values

Assessment • Environmental Impact Assessment • Legal and Regulatory Assessment

Source:- “South Africa Energy Storage Technology and Market Assessment”, for USTDA, Activity Number: 2015-11032A, 2017.

Monitoring and Control· Energy Conversion

· System Control

· Grid Communication

Component

(cell & stack)

Manufacturing

Materials

Manufacturing

Raw Material

Mining and

Refining

Balance of Plant Systems / Container Assembly· Battery Management

· Safety / Containment

· Environmental Controls

Energy Storage Module

Module & Pack

Assembly

ESS System Integration and Construction

ESS Operation

ESS

Maintenance

and Renewal ES

S D

eco

mm

isio

nin

g a

nd

Re

cyclin

g

ESS Project Development and Finance

Energy Storage Value Chain

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Conclusions

• Large growth in global energy storage deployments

• Energy Storage needs to be deployed to attract stacked values

• Technology and Energy Management System are key factors in

attracting stacked values with positive business case.

• Energy storage need to be validated and tested

• Roadmap with energy storage life-cycle analysis is key for positive

value chain.

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Thank You. Questions?

Contact: Dr. Johan Enslin

Executive Director and

Duke Energy Smart Grid Endowed Chair

jenslin@clemson.edu; 843-730-5117

www.clemsonenergy.com