Experiences and Initial results from Terna’s Energy Storage Projects

Anna Carolina Tortora Head of Innovation Research and Development

1 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

2 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

3 Terna is….

. ...the largest independent transmission system operator (TSO) in Europe and the sixth in the world . ...the owner of the Italian High Voltage National Transmission Grid . ...responsible for the transmission and dispatching of electricity throughout the Country . ...in charge of the development and maintenance of the Grid, employing a workforce of ~3,500 . ...listed on the Italian Stock Exchange since 2004, with a market cap of about € 8,7 Billion.

Numbers ... … and Premises

Grid ~ 72,000 Km of three-phase conductors in 22 Interconnections lines with foreign countries 841 Substations

Montenegro Assets 8 Transmission Operating Areas 8 Distribution Centers 3 Remote-Control Centers

1 Foreign Subsidiary Serbi a Electricity Market 310 TWh of energy consumption (2014) Transmission Operating Areas 59,400 MW demand peak (July 2015) Distribution Centers Remote-Control Centers Foreign Subsidiary

4 4 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

5 The Italian Context…back in 2010

Causes Effects Mitigating actions

•Economic crisis and subsequent • Fast and massive growth of RES: loss of many big consumers (i.e. Rise in congestion-related curtailments national demand decreased 7% (i.e. 2010 500 GWh lost) from 340 TWh to 318 TWh) Rise in demand for non-spinning Optimize integration of RES and •Aggressive policy of incentives reserve increase flexibility of national promoting RES + imminence of • Traditional power plants running at grid (i.e. smarter grid) grid parity minimum load: •Short time to fortify and develop  Loss of inertia in smaller insular the grid to support new scenarios systems (i.e. Sicily and Sardinia)  Loss of available frequency reserves

Optimize RES Integration and increase system’s reserves Ease Power Problem Congestion Energy Problem

Compensate for low inertia

6 The Tools for the Defense of the Grid

Past Future

The physical resistance (inertia) of the system against frequency change due

to an imbalance.

Instantaneous/ Spinning Reserve Spinning

Ensures that

f Imbalance Primary Secondary Tertiary power Primary frequency (in Stops Imbalance

Europe) is

Primary Regulation

always kept at

50 Hz

Time

Ensures that

power frequency Power (in Europe) is brought back to

50 Hz

Regulation

Secondary

Partially complements Time and finally replaces 30 Seconds all of Europe responds Secondary Reserve by

re-scheduling 100-200 Seconds The country in which the event happens responds

Tertiary Regulation

generation. 15 – 120 Minutes The country in which the event happens responds

7 Distributed The adequacy The Changing Generation of the Grid Energy Mix Definition methods methods are necessary alone ineffective so new makes approach this increase The net in Means that all of of demand highest assessing point the evaluated by traditionally Has been tomorrow’s Grid today’s asaswell be adequateto assets planned must Scenarios Different Asset to react to Capacity of an Defined as the Flexibility Focus on Loss of Inertiaand of Flexibility

is is

DG DG

Generation Loss

of

a

Group

caused

coupled

a

very

fast

with

Frequency

the Example 2011Event in Sicily

<10 <10 s system’s Group Event: Loss of a Generation

drop

PV 49.7 Hz: Loss of Distributed

and very Load Shedding 49 Hz: Activation of Emergency

the

low

activation

Inertia

of and

Emergency

the

high

Load

amount

Shedding

of

Distributed

8

Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

9 Terna’s Energy Storage Strategy

Analysis of Storage Knowledge of different TECHNICAL ANALYSIS BEST TECHNOLOGY PER applications energy storage APPLICATION technologies Testing phase to analyze

the technology’s Selection of the constraints Market arbitrage/load technologies shifting Transmission

avoidance/deferral

Energy intensive applications

System operationPrimary reserve

ORIGINATION ECONOMICAL ANALYSIS Secondary/tertiary reserve Benefits’ evaluation and Distribution Costs’ quantification avoidance/deferral

PV and storage

Off-grid

DEFINITION AND DEVELOPMENT OF A VIRTUAL STORAGE PLANT A Platform capable of integrating the characteristics and limitations of each technology while maximizing their performance and reducing additional costs stemming from non-optimal usage

10 Consumers System Operators Generators There are Many More Applications… Consumers and Domestic ConsumersConsumersand Large Public Service, Industrial DistributionTransmission and Thermal and Renewable

Generators

T&D T&D InvestmentDeferral/Avoidance OptimizationConsumption ofFuel Support to EnergySupportEfficient Techs Secondary Reserve( Secondary Primary Primary Reserve Compensation Regulationto Grid Services Primary ReservePrimary ( Renewable Management Congestion Management Generation Smoothing Demand ManagementDemand SyntheticInertia Load Following Peak Shaving UPS Service UPS E - mobility

f

f and V) and

and V) and

11

Terna’s Storage Technology Portfolio

30 -60 seconds 0,5 – 1 hour 2 – 4 hours P & E are decoupled 7 hours

• Procurement

on going Power Intensive Power 9,2 MW 3,4 MW 0,85 MW 35 MW Intensive Energy installed installed procured installed

Grid support (e.g. frequency regulation)

Grid Defense System Congestion management

Power Quality & UPS Load Shifting Main applications

12 Terna’s Storage Projects

Energy Intensive Power Intensive • Mission : reduce grid congestions • Mission: increase safety of grid • Total Power: ≈35 MW • Total Power: ≈ 40 MW • Solution: NaS Sodium Sulfur • Solutions: Li-Ion, Zebra, Flow, Supercaps • Number of sites: 3 • Number of sites: 2 • Investment Size: 160 €mln; • Investment Size: 93 €mln;

Site 1: Ginestra • Total Capacity: ≈ 12 MW PHASE I: 16 MW Storage Lab • Status: operational Site 1 Codrongianos • Total Power: ≈ 9,15 MW Site 2 • • Status: operational ≈ 5,4 MW Total Capacity: ≈ 12 MW • in commissioning ≈ 2,1 MW Status: operational under construction ≈ 0,4 MW procurement initiated ≈ 1,25 MW Site 3 Site 2 Ciminna • Total Capacity: ≈ 10.8 MW • Total Power: ≈ 6,8 MW • Status: operational • Status: operational ≈ 5,1 MW under construction ≈ 0,45 MW tender to be submitted ≈ 1,25 MW

PHASE II: 24 MW Casuzze and Codrongianos: to be initiated

13 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

14 Power Intensive Projects

1st Phase Storage Lab (16 MW) 2nd Phase (24 MW)

Sardinia: Sardinia: 10 MW 12 MW Codrongianos Codrongianos

Sicily: Sicily: 6 MW 12 MW Casuzze Ciminna

Provide essential services: • Frequency regulation; Develop an Advanced • Secondary Regulation; Assess the performance Control System for the • Integration in TSO’s characteristics of multiple management of multiple control systems; Energy Storage Systems EESS Technologies (Virtual Storage Plant) OBJECTIVES • Power Quality.

15 Energy Intensive Projects

Benevento 2 – Celle San Vito Benevento 2 – 380

IVPC VOLTURARA CAMPOBASSO

EDENS VOLTURARA VOLTURARA CERCEMAGGIORE MONTORSI IVPC ALBERONA

FLABRUM WIND ENERGY EDENS ALBERONA ALBERONA IVPC POW3 FOIANO CASTELPAGANO FOGGIA FOIANO ROSETO IVPC4 ROSETO ASI T. FV IVPC EDENS C.S.V. TROIA FOIANO FEO FORTORE E. R. DAUNIA SEA 12 MW EDENS S. FAETO MARGHERITA FOIANO GIORGIO L.M. MONTEFALCONE CELLE S.VITO COLLE SANNITA EOS FAETO FORTORE E. GINESTRA CER EOS4 F. CASTELF. IVPC4 C.S.V. 12 MW GINESTRA DEGLI MARGHERITA F.. IVPC M. SCHIAVONI W.F. U. SAVIGNANO FS EDENS M. AVINO DAUNIA W. Flumeri ECOENERGIA MONTELEONE DAUNIA CALVELLO SAVIGNANO IRP.

ARIANO IRPINO

PRESENZANO BENEVENTO APICE FS NUOVA SE BENEVENTO IND. GONGOLO GONGOLO BENEVENTO 2 BENEVENTO FS Ginestra FLUMERI S. SOFIA FOIANO

AIROLA / MONTEFALCONE TROIA MONTESERCHIO

AVELLINO SAVIGNANO FS

SAVIGNANO ACCADIA IRP. PRESENZANO BENEVENTO APICE FS ARIANO VALLESACCARDA BENEVENTO 2 BENEVENTO IND. BENEVENTO FS SCAMPITELLA FLUMERI DURAZZANO BISACCIA AIROLA S. SOFIA STURNO MONTESARCHIO

BISACCIA

X MATERA X PRATA P.U. FIAT PRAT.S. UTE NOVOLEGNO Provide essential services: FMA PRATOLA SER. GOLETO 12 MW S.ANGELO CASTELNUOVO N Reduce local •Frequency regulation; congestions on • Secondary Regulation; Scampitella CONTURSI FS TUSCIANO CONTURSI MONTECORVINO BUCCINO the HV grid SICIGNANO •Tertiary reserve; CAMPAGNA TANAGRO

LAINO ROTONDA OBJECTIVES •Voltage Support.

16 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

17 Overview of Terna’s Testing Activities

•Frequency Regulation Purpose of testing is to collect enough knowhow to be able to select the best •Grid •Voltage Regulation

technology according to the desired Scale(>1MW) •Power Quality application •Increase in Reliability

testing •Grid Stabilization The Storage Lab project has been •Efficiency analysis designed to analyze the Focus om EESS’s EESS’s om Focus performances of selected

technologies when used to solve

Network issues

START ?

• Aging Test Technologies: •Module scale •Lithium-Ion • Performance Test (<100kW) •Zebra • Thermal Test •Supercaps • Overcharge/discharge Test •Flow Testing • Overload Test

• Short Circuit Test Focus on Modules’on Focus

Module Tests executed by: Lab

18 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

19 Grid Scale – AC/AC Round Trip Efficiency Test

Purpose of testing

Validate the performances of each EESS in terms of: Targets Nominal Energy Efficiency of the system

Standard cycle: the cycle used consists in a discharging phase followed by a charging phase;

during the test it is admited the interposition of

Definition and stand-by phases validation of procedures Each technology supplier has been requested to propose the profile of the cycle to be used

cycle Standard during the test session (*) Test Execution Active Power (MV) Discharging Phase Active Power absorbed by auxiliaries (LV) Charging Phase

Acceptance criteria

Analysis and validation of •Correct execution of the cycle proposed without any interruption or abnormal behavior results •Discharge energy and efficiency of system (including auxiliaries consumption) should be compliant with the Technical Specifications requests

(*) the cycle will be repeated 3 times on order to validate the results 20 Grid Scale – AC/AC Round Trip Efficiency Results

Energy absorbed E during charging phase Energy released during in discharging phase Eout EESS Energy absorbed by auxiliaries during charging

Eaux phase (Eoux, in) and during discharging phase (Eoux, out)

System Technology AC/AC Efficiency

SODIUM NICKEL CHLORIDE ̴ 80%

(*) SODIUM NICKEL CHLORIDE Data not available yet

LITHIUM TITANATE ̴ 86%

LITHIUM IRON PHOSPHATE ̴ 83%

LITHIUM NICKEL COBALT ALUMINA ̴ 84% (**)

LITHIUM MANGANESE ̴ 85%

(*) LG Batteries LITHIUM NICKEL MANGANESE COBALT Data not available yet

(*) Installed only in Sardinia 21 (**) Result obtained in Sardinia Site, in Sicily the efficiency is lower due to the different capacity of the system Grid Scale – First islanding on HV Grid 4 EESS installed at the Codrongianos substation were successfully tested in an islanding procedure involving one Synchronous Compensator (250 MVA), one ATR 380/150 kV (250 MVA), one 150/15 kV transformer and two busbar assemblies (380 and 150 kV)

System in Islanding Batteries start giving power

Island at steady-state 50,2 Hz Island’s frequency 50,1 Hz

50,0 Hz

49,9 Hz

49,8 Hz Synchronous ATR Storage Lab Compensator 4 MW

2 MW P From Storage Lab 380 kV

0 MW 150 kV 0,5 s 220 kV 3 s

Scope of the test was to demonstrate the effective use Energy Storage Systems as a means to increase grid reliability

22 Grid Scale – Short Circuit Test

The test was performed in order to verify the correct behavior of the inverters during a short circuit while in islanding mode

Fault Recorder

MV protection

SCI

The inverter control system interrupts the current almost instantly PCS (few milliseconds)

Controller

EESS n EESS

EESS 1 EESS 2 EESS

BMSBMS MV Protections are to slow to correctly identify the fault and open the circuit.

(*) MV: Medium Voltage 23 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

24 Lab Scale – Aging Tests During the tender phase it became necessary to create a standard cycle in order to best compare and rank the different technologies

1,5 CiclaggioStandard Standard Cycle

1 • Discharge @ Pn, DOD 80%;

0,5

.] • Complete Charge @ Pn; 0

p.u 0 1 2 3 4 5 6 7 8 P [ P Potenza [pu] -0,5 • No resting time between one -1 Procedure Test cycle and the other(*) -1,5

Furthermore, to compare each technology against the frequency regulation service, another cycle profile was identified: it was obtained by taking a real continental 24h frequency signal, filtered and compressed in order to attain a meaningful and challenging power profile (average value 50 Hz, max frequency deviation > 100 mHz)

FrequencyAndamento frequenza behavior 50,15 Service parameters: •Frequency droop 0.075%; 50,1 •Deadband 0 mHz. •Starting SOC: 100%;

50,05 [Hz]

•SOC max :100% (no over-charge);

50 •SOC min: 0% (no over-discharge);

Frequenza [Hz] Frequenza 49,95 •If SOC min is reached, then recharge the battery and nominal

Frequency power and continue with the power profile;

49,9 Procedure Test

49,85 •Every10 days the reference cycle will be executed in order to 0 10000 20000 30000 40000 50000 60000 70000 80000 90000 timetempo [sec] [sec] determine the electrochemical parameters of the battery.

* This procedure was adapted for each supplier in order to account for the specifics and limitations of each technology 25 Lab Scale – Comparison Between Aging Cycles Compared to the standard cycle, the frequency regulation cycle is, from a thermal and energetic point of view, less stressful and yet…

Power profile for frequency regulation service

] • Average power:

pu

P [ P •Standard Cycle: Pn •Regulation cycle: 0.4 Pn

•Daily equivalent(*) cycles: time 1,5 CiclaggioStandard Standard Cycle •Standard cycle: 5-12 1 •Regulation cycle: ≈5

0,5

.] •Daily power inversions:

0 p.u

0 1 2 3 4 5 6 7 8 cycles between Comparison

P [ P Potenza [pu] -0,5 •Standard cycle : max 24

-1 •Regulation cycle : over 1000

-1,5 …Tests have shown that frequency regulation cycle ages batteries much more than the standard cycle

* Equivalent cycles are obtained dividing the daily energy discharged, by module’s nominal energy 26 Potenza [pu] - - P [p.u.] 1,5 0,5 0,5 1,5 - 1 New test profile 0 1 0 Lab Scale

- - - - - C-Rate 0.2 0.4 0.6 0.8 1.2 1.2 0.8 0.6 0.4 0.2 1 - In In toif verifyorder frequent numerousand inversionspower impact aging the of 1 0 1

0

2 30 Ciclaggio Standard the the batteries morethan heata cycleenergy ornewhas defined been

60 Standard Cycle 3

90

120 New 4

150 time time [sec] Cycle – 5

180

Next Aging Next Aging Tests

210 6

240 7

270

300 8

330

• • •

Daily Daily power inversions Daily equivalent(*) cycles Average C P [pu] Power Power profile for frequency regulation service - rate :

:

time :

Test initiated in in 02/2016

≈ 0.46 ≈ 2800 5.6 27

Lab Scale – Test results Standard Cycle TERNA Regulation Cycle TERNA 100% 100%

95% 95%

E % E % E

90% 90%

No test data available for Lithium 1 (next gen). 85% 85% 0 200 400 600 800 1000 0 200 400 600 800 1000 Equivalent cycle Equivalent cycle

Module Number of cycles Technology Cycle under test 100 200 300 400 500 1000 1500 2000 2500 3000 4000 5000 6000 Standard Cycle Terna 100% 95% 85% 75% ------Lithium 1 NCA Regulation Cycle Terna 98% 95% 88% ------Data at- Jenuary- 2016 - Standard Cycle Terna 99% 98% 97% 97% 96% 94% 93% 92% 91% - - - - Lithium 2 NCM Regulation Cycle Terna 100% 100% 98% 97% 96% 90% ------Lithium 1 (next Standard Cycle Terna 100% 99% 99% 98% 97% ------NCA gen) Regulation Cycle Terna ------Standard Cycle Terna 100% 99% 98% 97% 97% 96% ------Lithium 3 LFP Regulation Cycle Terna 97% 95% 94% 94% 92% ------Standard Cycle Terna 100% 99% 99% 99% 98% 96% 96% 94% 93% 91% - - - Lithium 4 LMO Regulation Cycle Terna 100% 100% 99% 98% 97% 95% ------Standard Cycle Terna 100% 100% 100% 100% 100% 99% 98% 97% 96% 96% 95% 95% 94% Lithium 5 LTO Regulation Cycle Terna 100% 100% 99% 99% 99% 99% ------

* Equivalent cycles are obtained dividing the daily energy discharged, by module’s nominal energy 28 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

29 Lessons learned Thanks this toexperience, Terna achievedhas asignificant learning amount expertise. of and Main lessons learned To date Ternastorageof commissionedhasMWh270more MWthan / 47 systems. (*)The (*)The four arephases mostlyrelated to Lithium and Zebra technologies Procurement

Design Howtocalculate cost real different the the of technologies

Learned Know How controltoimprove systemthe the of (*)

How to better specify what we need we Howtobetter what specify Construction& -

Installation how in in maintenacemanagementandhow

Today Operations Still Still learning…

30

Service Technology requirements Technology Requirements requirements requirements Service Evolution of the Technical Requirements • • • • • •

challenging enough Defense systemintegration Tertiary regulation Secondary regulation Primary regulation Roundtrip efficiency not Minimum cyclelife not required Technical Requirements 1.0

2012

• • • • • • • •

Other Other smartapplications grid Defense systemintegration Tertiary regulation Secondary regulation Primary regulation detailed Inverters works more Civil and challenging required Technical Requirements 1.1 Roundtrip efficiency more Minimum cyclelife not 2014

-

2015

Technical Requirements 2.0 Future installations

31

Control, Maintenance and Operations

•Each solution needs specific signals and •Terna’s operator needs an adequate alarms for optimal management selection of commands/alarms for

optimal assets management

Identification of the most relevant signals/alarms

Unbalanced cells

•Some modules disconnect due to unbalanced cells (placed inside) and no critical alarm is generated because

the system can still ensure nominal power. Most needed improvements needed Most

Significant alarms have to Smart “balancing solution” be generated when a has to be developed specific number of (balancing cycle/ modules are disconnected SOC calibration)

32 Importance of Thermal Design

Module’s thermal design greatly modifies the System layout and Performances performances of the complete system Lithium 3

Adding a fan and metal heat sink to the module’s design allows the system to cycle continuously without needing stand-by phases for ensuring cycle life

Three hours stand-by needed Codrongianos

Lesson learned and applied to Ciminna installation

Continuous cycling Ciminna

33 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

34 New Technologies (1of2) – Redox Flow Batteries Redox Flow Batteries A Redox Flow Battery system is made up of a number of electrochemical cells. Each cell has two compartments, on for each electrolyte, usually physically separated by a membrane. The electrolytes are stored in two tanks and are pumped through the cell stack across the membrane where one form of the electrolyte is oxidized and the other is reduced during discharge and vice-versa during charge.

EESS Installation Tipical size: during P: 0.4 – 0.5 MW 2016 E: 1.0 – 1.5MWh

35 New Technologies (2of2) – Super-capacitors

There are two main categories of Supercapacitors

Electrical Double Layer Capacitors (EDLC) Hybrid Capacitors

•The electrical charge is electrostatically stored in the • The basic design of a hybrid SC uses two electrodes made double-layer, naturally formed at electrode-electrolyte of different materials and, eventually, using different interface under voltage. operating processes •Hybrid structure: energy is stored both electrostatically •Electrodes are usually made of Active Carbon and chemically •Negative Electrode is made of graphite like lithium-ion batteries

Tender to be published during 2016

36 Agenda

Introduction to the TSO

The Context

The Approach to Energy Storage

The Projects

The Tests • Grid Scale • Lab Scale

Main Lessons Learned

Future Developments

Annex

37 Codrongianos – Installation Layout Tecnologie installate Lithium Iron 1 MW 1.231 MWh Phosphate

Lithium Nickel 1.2 MW 0.928 MWh Cobalt Aluminium

Lithium 1 MW 0.916 MWh Manganese Oxide Lithium Nickel 1.08 MW 0.540 MWh Cobalt Manganese

Lithium 1 MW 1.016 MWh Titanate

1,2 MW 4.15 MWh Sodium–nickel Other Technology 1 MW 2 MWh Sodium–nickel

Other Other Technology Technology

7 Ciminna – Installation Layout

Tecnologie installate

Lithium Iron 1 MW 1.231 MWh Phosphate

Lithium Nickel 0,9 MW 0.570 MWh EPC Cobalt Aluminium

Lithium 1 MW 0.916 MWh Manganese Oxide

Lithium 1 MW 1.016 MWh Titanate

1.2 MW 4.15 MWh Sodium–nickel

Altre tecnologie

Altre tecnologie Altre tecnologie

39