Overcoming Intermittency in Renewable Energy through Storage Systems

Irene FastelliENEL Ingegneria & Innovazione

Agenda

Enel Group

Renewable into the grid

Approaches to compensation

Scenario

Enel Group on-going programs and next activities

Enel, an international GroupA global dimension

NORTH AMERICA• Enel’s Installed capacity

749 MW

LATIN AMERICA• Enel’s capacity 667 MW,

Endesa’s capacity 15.284 MW

• Endesa’s customers 12,4 mn

Americas

(1)2008 pro-forma data with Endesa, OGK-5 and Electrica Muntenia Sud consolidated respectively at 100%. Data net of assets to be disposed to Acciona

(2) Value corresponding to 50% of Eufer’s total capacity

FRANCE• 12.5% EPR project, • Wind capacity 12 MW

SLOVAKIA•66% of Slovenské

Elektrárne: installed capacity 5.705 MW of nuclear, thermal and hydro capacity

Europe

SPAIN AND PORTUGAL•92% of Endesa (22,123

MW, 12.6mn customers)•Total net production of

31.4 TWh•50% of EUFER: 399 MW2

GREECE• Renewables 112 MW

MOROCCO• Endesa’s installed

capacity 123 MW

94,3 GW of installed capacity61 million customers

83,300 employees

BULGARIA• 73% Maritza• Capacity 602 MW

ITALY•Enel’s capacity 40.323 MW

ow Enel’s Green Power 2.547 MW.

•Total Net Production: 96,3 TWh.

•Enel’s customers 33.1 mln

RUSSIA•49.5% of RusEnergoSbyt•40% of SeverEnergia gas

reserves (total 700 bcm)•55.8% of OGK-5 (installed

capacity 8.183 MW)

ROMANIA•51% Banat & Dobrogea

and Enel Energie•64.6% Electrica

Muntenia Sud•2.6mn customers

Source: Company information.Note: Presentation includes consolidated financial and operating data unless otherwise stated.

Capacity as of 30 June 2010 - Production end 2009 PF - Pipeline and in execution data as of 30 June 2010.(1) Includes ENEOP (Portugal), 137 MW in execution. Equity consolidated as of 30 June 2010; full consolidation is expected in 2013.(2) Ongoing disposal process of Bulgarian assets, which are included in the figures.

EGP presence

North America

Operating

788 MW

Production

2.4 TWh

In execution

0.3 GW

Pipeline

8.3 GW

Global leader in a growing industryEGP global footprint – H1 2010

Unrivalled footprint in 16 countries across all main renewable technologies

Iberia and Latin America

Operating

2,076 MW

Production

6.4 TWh

In execution

0.5 GW(1)

Pipeline

15.6 GW

Italy and Europe(2)

Operating

2,897 MW

Production

12.0 TWh

In execution

0.4 GW

Pipeline

5.8 GW

Enel Green Power

Operating

5,761 MW

Production

20.9 TWh

In execution

1.2 GW(1)

Pipeline

29.9 GW

Renewable into the grid

Wind and Solar PV fluctuations

Implications for compensation

Day-night fluctuations(PV only)

Seasonal fluctuations(climate)

Medium term fluctuations

Short term fluctuations

Cyclical, predictable

Erratic, unpredictable

Fluctuation pattern Compensation

• Recurring patterns with specific regional variations

• Balance residual load with flexible generation

• Improvements through better forecasting are possible

• Need to balance fluctuating renewable to ensure the security of the overall energy supply

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Needs for compensating capacity

*Courtesy of IHS Emerging Energy Research

Approaches to compensation

Integration of intermittent renewables

Approaches to compensations

Interregional compensation (grid extension)

Conventional backup capacity

Demand side management

Large scale electricity storage

Each has its strength and limitations!

Approaches to compensation

Limitations

Grid extension

• It cannot mitigate all types of

fluctuations (e.g. day-night fluctuations)

• Political barriers to implementation

(public resistance, permitting process)

• Energy losses in transmission

Backup power

Increasing dependence on fossil fuel

Uncertainty regarding fuel prices

Risk of low utilization

Requirement of decentralized unit

where small scale wind and PV are

present

Demand side management

Most loads can be deferred for a short

period of time

Requires behavioral adaptations by

customers and adequate pricing

flexibility to actually drive changes

The potential demand reduction is a

small percent of peak load

Approaches to compensation

Electricity Storage – a key enabler

Self-sufficient solution

Not affected by increases in renewable penetration

Possibility of having decentralized units

Cost-effectiveness is the key weakness of storage

technologies

Technologically it is still relatively immature for large

applications other than hydroelectric storage

Pros Cons

Most promising technologies for large-scale application

Market ready Prototype

Hydro pumping A-CAES

CAES Batteries

Conventional batteries

UC

Hydrogen

Technologies for large scale applications

Pumped hydro

Profen technology

High efficiency

Relatively low specific storage capacity

Main limitation: New sites hardly possible to develop

DERIVAZIONE CatUnità di Business

N° gruppi

Pot. eff.

(MW)

Potenza turbine (MW)

Potenza generatori

(MVA)

Produc. nat. Serie 68-02

(GWh)

Produc.da pomp.vol.

(GWh)

Prod. totale (GWh)

Anno Tipologia gruppi

ANAPO PP SICILIA 4 500,0 600,0 660,0 0,0 588,8 588,8 1989 Gruppi reversibili monostadio ae/as

BARGI PP BOLOGNA 2 330,0 338,1 370,0 0,0 348,6 348,6 1975 Gruppi reversibili monostadio ae

EDOLO PS BRESCIA 8 977,6 1.019,6 1.280,0 209,2 683,0 892,2 1983 Gruppi reversibili 5 stadi ae (1)

ENTRACQUE CHIOTAS PP CUNEO 8 1.065,0 1.182,6 1.360,0 49,5 1.190,7 1.240,1 1980 Gruppi reversibili 4 stadi ae (1)

ENTRACQUE ROVINA PB CUNEO 1 125,0 133,7 150,0 2,8 46,8 49,6 1980 Gruppo ternario mono/bistadio

PRESENZANO PP NAPOLI 4 1.000,0 1.000,0 1.200,0 13,6 1.245,6 1.259,2 1991 Gruppi reversibili monostadio ae/as

RONCOVALGRANDE PP SONDRIO 10 1.000,0 1.020,1 1.124,0 19,9 833,3 853,3 1971 Gruppi ternari pelton/4 stadi

S.FIORANO PS BRESCIA 2+2 568,0 560,4 621,1 345,0 170,0 515,0 1973 Gruppi ternari pelton/6 stadi (2)

TALORO PS SARDEGNA 3 240,0 264,5 285,0 27,1 196,4 223,5 1980 Gruppi reversibili monostadio ae/as

ae: avviamento in pompaggio ad albero elettrico (back-to-back)as: avviamento in pompaggio con avviatore statico

(1): gruppi non modulabili(2): due gruppi ternari di generazione e pompaggio e due gruppi di sola generazione

Dati caratteristici degli impianti

Pumped hydro will continue to be the leading storage technology in terms of installed capacity

More than 5,2 GWh installed capacity in Italy

Technologies for large scale applications

Compressed Air (CAES)

Diabatic CAES

Wide output power control range Relatively low investment costs Low cycle efficiency of up to 0,55 Main limitation: storage sites

2 CAES Projects, 450MW, in Stimulus Package

Huntdorf, Germany, 290 MW

McIntosh, Alabama, 110 MW

Advanced CAES plants are expected to be significantly more efficient.

Enel is carrying on engineering research to validate economic and technical viability of different solutions

Scenario

Smart energy management

How to get there?

1. Identify flexibility needs

2. Identify best storage technologies and competing alternatives

3. Analyse the trade off between storage and its competing options

4. Allow for markets and legislation to foster the environmentally best option

5. Analyse, suggest and implement the storage and generation mix best suited for a low carbon

energy system

Generation portfolios with and without storage

*Source: BCG “Revisiting energy storage”Load profile based on average data for January and June 2009 in Germany.

Storage can increase the share of base-load power generation

Without storage: 25 GW baseload With storage: 30 GW baseload

Storage services

2 3 4 51

• Market regulations regarding ancillary services

• Strategic planning

• Large scale introduction of renewables

• Emission benefits

• Energy management

• Reserve/regulating power

• Integration of large scale renewables

• Ancillary services

• Transmission& Distribution services

• Customer site applications

• Load management & response

• Emission benefits

• Load management

Storage can provide several functionalities:Different applications are best served by different technologies

Enel Group on-going programs and next activities

ENEL approach to tackle over the topic

Value chain

Modeling, technical feasibility

Economic, environmental, organizational aspects

Experimental validationShortlist of

“opportunities” for storage systems

• T&D curtailment

• Time-shifting

• Forecast hedging

• Frequency control

• Voltage control

• Ancillary services

• Revenues

• Industrial maturity

• Operating constraints

• Environmental impact

• Public acceptability

• O&M costs

• Key Performance Factors

• Service life

• Best practices

20

ENEL projects

2008

Test

Faci

lity

Liv

orn

oC

anary

Isla

nds

Dem

o P

roje

ct

2015 20162009 2010 2011 2012 2013 2014

Experimental characterization and

model validation

Quantification of benefits that energy storage systems can provide to renewable plant

Characterization of promising lab-scale technologies in different operating conditions

Demonstration of market ready storage technologies integrated in island grid

Engineering & permitting

Procurement and systems integration

Test and optimization

I ntegration of a demo scale energy storage system in a wind farm

Detailed engineering of integrated system

Procurement &commissioning

Monitoring and operation

ENEL Storage Test Facility - Livorno

Objective

Characterize promising lab-scale storage technologies

Identify the key aspects for large scale implementation of storage technologies and their actual suitability to the different requirements for Enel applications

Define storage systems optimal management strategies to ensure renewable production programmability

Develop guidelines and best practices for the selection, installation and use of ESS for ENEL applications

Assess and model the influence of operating conditions on system performances

Electronic system able to reproduce typical renewable generation and load profiles

Reproduction of wind and

solar generation up to 50kW

Reproduction of DSO requests

up to 50 kW

Capability to operate and

characterize several systems

at the same time

Response time ~ 1 sec

PLC management & PC

control

Automatic execution of more

than 400 steps

ENEL Storage Test Facility

Test rig

Performance monitoring and recording

Measurement of AC /DC data

Acquisition of data communicated by

storage systems

ENEL Storage Test Facility

First technologies characterized

Vanadium Redox Flow battery

10kW 100kWh

ZEBRA battery

20kW 20kWh

Li-ion battery

15kW 15kWh

Economic KPIs

Operating KPIs Response and inversion time

Time at rated power

Round trip efficiency

Real vs nominal capacity

Performances decay

Key performance factors investigated

Enel Storage Test Facility

2011 Installations

20 kW PV plant

100 kWh H2 storage on

metal hydride

EV quick charge point (<20mins)

CHAdeMO compliant

•Conduct engineering research to

validate economic and technical

viability of applications

•Continue monitoring technological

developments: performance

improvements, other technologies, cost

reduction

•Refine benefit calculations with results

of ongoing experimental

characterization

•Update strategic planning figures with

new information

Next steps

Micro-wind generators

Optimize the integration of distributed energy resources (stochastic renewable generation, EV and storage) connected to the distribution network.

“STORE” – Demonstration Project

Managing generation on island systems

Demonstration of different storage technologies capabilities to solve problems of grid congestion and to damp fluctuations in the Canary Islands.

NaS Technology – 1MW, 6MWh

Installation in Gran Canaria to replace diesel

peak generation, voltage support, load leveling,

etc.

ZnBr Technology- 500kW, 2.8MWh

Mobile installation in La Gomera to replace

peak generation

UC Technology – 4MW, 5-6sec

Integration in diesel power station in La Palma

(fast event response)

Hydro-wind power facility

El Hierro Project – Endesa partecipation

Wind power: 20 MW

Hydro generation: 13 MW

Pumping :16 MW

Grid stability is guaranteed by the continuous operation of the hydraulic group

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Key open questions

The main issues regarding new storage systems (batteries,

compressed air, etc.) are:

• Assessing availability and quality of flexibility resources

• Minimizing the cost of procuring flexibility

• Testing / demonstrating the operational viability of storage in

our grid

• Developing optimal control devices and strategies

• Refining benefit /cost valuations with new information

• Addressing potential regulatory issues in this space

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Thank you for your attention!