Storage for a sustainable future The Global Leader in Advanced Energy Storage

Prudent Energy

Global Deployment of Prudent Energy's VRB® Energy Storage Systems and its applications in the German Market

Hugh Sharman – Prudent Energy

Georg Von Kriegsheim – Allmerus Energy at

IRES 2011

• Provides proprietary VRB® energy storage systems (VRB-ESS®) for grid

and renewable energy storage applications

• 10 years operations with the VRB® technology

• Over 20MWh commercial sales in last year

• Employees: ~200

• Manufacturing capacity: 15MW 100MWh per shift/year

• VRB and storage application Patents: control all substantial patents

including 44 issued patents and 56 pending patent applications in 34

countries

• Major Investors: MITSUI Corporation, State Power Group, DFJ and DT

Capital & others

Company Overview

About Prudent Energy

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• Renewable energy management team with focus in the fields of storage,

solar production technology, biomass, international wind, and geothermal

projects

• Active since 2002

• Managing partners have held senior positions within German and American

utilities (E.ON, Tennessee Valley Authority, Thüga)

• Deep insights in the German and European energy markets

Company Overview

About AllMerus Energy

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• AllMerus Energy has been mandated by Prudent Energy to evaluate, build

up, and manage sales of storage solutions in Germany

• Close coordination with Prudent Energy. Buildup of a joint Sales and Asset

Management company structure.

• Primary Focus on MW size storage solutions

• Discussions ongoing with wind and solar park owners and developers,

utilities and project developers

• Several concrete projects under discussion.

Company Overview

Cooperation Prudent Energy & AllMerus Energy

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• Significant curtailment of wind

generation during grid congestion

periods causing localized energy

losses of up to 20% of annual

production

• Major projected increase of

stochastic power production in

the future with continued wind

and solar developments

• Increased strain on distribution

grid

• Higher volatility of power prices

caused by unmanageable

periodic market surplus of

renewable energy.

Market Conditions

Market Potential of Storage Solutions in Germany

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• Reduce or avoid energy losses

by storing energy during

curtailment events to be supplied

to the grid post-curtailment event

• Offer reserve capacities/ ancillary

services in order to support

stabilization of local and regional

grids

• Increase market value of

renewable energy by storing

during low price periods and

selling it later at peak prices

Opportunities from Storage

Prudent VRB Technology

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Advantages

No daily “off periods” - always on

Power and energy capacity can be

sized independently

Can operate at ANY SOC without life

impact

Lowest total cost of life - unlimited

cycles of electrolyte with no loss of

any performance parameter

Electrolyte retains commodity value of

vanadium throughout life

Large surge capability possible

< 1 cycle responses

Disadvantages

Low energy storage density = big

footprint

Not mobile

Flow Battery Advantages and Disadvantages

Prudent Products

MW Class System kW class System

Cell Stack • Multi-cell stacks • Single cell stack

Capacity

• 200/300kW

Module

• Up to MW-class

system

• 5kW x 4 hour

• 5kW x 8 hour

Application

• Wind Farm

• PV

• Grid Expansion /

Enhancement

Peak shifting

• Telecom Base

Station

• Remote Area

Power Supply

• Mature and proven 7.5kW cell

stack

• Low cost injection molded frames

• Integrated seal design

• High scalability with parallel

connection

Standard Cell Stack Two Product Lines

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Recent VRB MW-Class system sales

Application Product Rating

Delivery

date Country

Wind Power Generation Research and

Testing Center

500kW/1MWh (750kW

pulse)

Jan. June

2011 China

Spanish renewable and micro grid

research center 65kW/ 200kWh

April Sept.

2011 Spain

Commercial food products – peak

demand shaving

600kW/3.6MWh (50%

pulse) Nov. 2011 CA,USA

PV integrated retail store – peak shaving 100kW/300kWh (25%

pulse) Dec. 2011 CA,USA

Indonesian island – micro-grid support 400kW/500kWh (50%

pulse) Dec. 2011 Indonesia

Waste water treatment plant – peak

shaving

1MW/6MWh (1.2MW

pulse) Mid. 2012 CA,USA

Grid connected Wind and solar power

smoothing and stability provision 2MW/8MWh (50% pulse) Dec 2011 China

Smart Grid islanded system 100kW 200kWh Jan 2012 Korea

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3,600 kWh VRB-ESS®

Peak Shaving

Gills Onion

Oxnard, California

9

300kWh VRB-ESS®

Renewable Energy (PV) Integration

SunPower, CPUC, PG&E, DOE, KEMA

California

10

Prudent Customers

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500kW 750kW pulse (10 minutes) / h

1MWh

One of three storage technologies

being evaluated in conjunction with

an existing wind farm in northern

China.

Results – one of other technologies

have failed inside a year

Our performance has been solid

Ambient temperatures down to -30C

Provides full rated REACTIVE energy

(MVAR) continuously

CEPRI, China

Prudent Customers

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100kW / 200kWh

Smart grid application- severe

single phase loading requirements

(100% imbalance per phase- wide

frequency deviations

Operated in a micro-grid to

perform output levelling and time

of day shifting

Provides reactive energy voltage

control dynamically

The micro-grid will be both grid

connected and islanded

CENER, Spain

Prudent Customers

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20kVa / 120kWh

Installed, August, 2007

Part of a micro-grid test facility

Extensive partial and deep cycling

thousands of times a year over 4 years

Risø, Denmark

Prudent kW class – Virtual power plant option

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Over 40 number 5 kW / 20kWh systems installed throughout the

world

USA (Alaska, Hawaii, Missouri, Virginia)

China

Kenya

Turkey

Italy

Denmark

Germany

Israel

India

Kenya system (pictured) in service

for more than 4 years. 15 units

kW-Class

Synthetic grid inertia - Dynamic Energy Storage is a

part of the solution Reserve Grid Power Stations

1 2 3

Operating Grid Power Stations

1 2 3

Renewable Grid Generation

1 2 3 4 5

Grid Frequency

Grid Power

1 2 3 4 5

The dynamic energy store acts as synthetic grid inertia to stabilise the grid until reserves can

respond. Distributed dynamic energy stores could either be added to each large renewable

farm to create a farm that operates like a power station but with FASTER response.

Grid Rotary

Inertia

Energy

Store

15

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Distributed Dynamic Energy

Storage

Generation Mix – Ramping and Stability

Average Wind Power Ramping: 0.5 MW/min or 0.5%/min

Example Grid Code ramping limits:

30 MW/min or 100 MW/10 min

5% rated/min Typical power plant ramping

capabilities:

Hydro 50%~100% per minute

Combustion gas turbine 20%~30% per minute

Coal plant 3%~5% per minute

VRB-ESS® 100% ramp rate in milliseconds – both ways

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Implications of PV and wind on Grid systems

• By adding wind and PV generation - volatility and power demand ranges are increased

• The mix of conventional generation must change when wind and PV generation is added in order to “follow load”

• so balancing and peaking type plant is required

– Causing higher cost, because of lower fuel efficiency

• …or base load plant must CYCLE causing…

– lower fuel efficiency

– Higher mechanical wear and tear

– Higher CO2 emissions

• The speed of response (ramp rate) for a rotating generator is 10 – 100 times lower than that of a dynamic energy storage system. Thus for equivalence, you require 2 to 4 times more reserve response generation than when using dynamic storage

Low voltage applications saving i^2R losses – reducing centralized peaking capacity

18 http://de.wikipedia.org/w/index.php?title=Datei:Lastprofil_VDEW_H0_Winter.png&filetimestamp=20100421075317

Saves line losses up to 25 times greater at peak & reduces need for inefficient peaking capacity

LV Power stored here

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Conclusions

• MORE fast acting “Generation = dynamic energy Storage” is required with wind and PV power as demand volatility increases

• Operation of storage at midpoint SOC allows for Up and Down ramping control – reducing curtailment and spillage

BUT ONLY CERTAIN TECHNOLOGIES can do this

• 6 to 8 hours of storage – provides stability AND captures spilled renewable generation

Can REDUCE RATES to stakeholders by at least 5%

• Multiple value streams are important – utility ownership of storage is best positioned to capture this

• Paybacks of under FIVE years are realistic

Prudent Energy Corporation

7200 Wisconsin Avenue

Suite 1002

Bethesda, Maryland 20814

Tel: 301-825-8910

www.pdenergy.com

Hugh.Sharman@pdenergy.com

tel+45 9825 1760

Georg Von Kriegsheim gvonkriegsheim@allmerusenergy.com

Main: +44 20 7796 1077

Mobile: +44 77 8098 0995