Presenter: Dr. Rahul Walawalkar Executive Director, India Energy Storage Alliance & President & MD, Customized Energy Solutions India Pvt. Ltd

1. Presented by
Dr. Rahul Walawalkar
Executive Director, India Energy Storage Alliance &
President & MD, Customized Energy Solutions India Pvt. Ltd
Energy Storage for Microgrids:
Poised for rapid adoption
Presented at

2. CES is at the forefront of
competitive electricity markets and
emerging technology trends
CES servicesClientsLocation
Industry orientationHeadcountHeadquarter
• US: 9 regional offices
covering PJM,
NYISO, ISONE,
CAISO, MISO,
ERCOT & SPP
• India
• Canada
• Japan
• Mexico
Philadelphia,
Pennsylvania
150+ Global
500+ Clients
Worldwide
Our consulting services enables competitive suppliers, technology providers, marketers,
utilities and customers to prosper through change, by turning knowledge into value

3. Select Global Emerging Tech Clients
3Confidential (www.ces-ltd.com)

4. Role of Energy Storage
in Indian Grid
Energy storage could play a key enabling role in every aspect of modern grid
including Generation, Transmission, Distribution and at Customer Premise
(including electric vehicles)

5. Current Status of US & India Projects
• US drivers
– Ancillary services
– Solar –storage integration for peak load
& demand charge management
– Microgrids for resilient grid / campus
– Diesel minimization in islands
• India drivers
– Diesel minimization for islands & C&I
– Renewable integration
– Energy access
– Ancillary services for Grid reliability &
power quality
Source: US DOE Energy Storage database & India Energy Storage Alliance

6. Microgrid Challenges
• Coordinated control of a large number of distributed sources with
probably conflicting requirements
• Limited communication imposes the adoption of distributed
intelligence techniques
• Management of instantaneous active and reactive power balances,
power flow and network voltage profiles
• Micro Grids are dominated by inverter interfaced distributed
sources that are inertia-less while traditionally, power grids are
supplied by sources having rotating masses which are essential for
the inherent stability of the systems.
6Source : Agarwal & Mittal Maulana Azad National institute of tech , Bhopal

7. MicroGrid Challenges
• Maintaining stability and power quality in the islanding mode of
operation requires the development of sophisticated control
strategies which need to be included on both generation and
demand sides.
• Transitions from interconnected to islanding mode of operation are
likely to cause large mismatches between generation and loads,
posing a severe frequency and voltage control problem.
• Instable operation during faults and various network disturbances
may occur if Storage components are not there.
• High resistance to reactance ratio of the low voltage networks,
resulting in strong coupling of real and reactive power. Hence the
control of voltage and frequency can no longer be considered
separately.
7Source : Agarwal & Mittal Maulana Azad National institute of tech , Bhopal

8. Microgrid – operational Challenges
8

10. Solar Smoothing and ramp Rate Control
10

11. Energy Storage for wind Smoothing
Wind Farm Output With Firming
9
10
11
12
13
14
15
1
68
135
202
269
336
403
470
537
604
671
738
805
872
939
1006
1073
1140
1207
1274
1341
1408
1475
1542
1609
1676
1743
1810
1877
1944
2011
2078
2145
2212
2279
2346
2413
2480
2547
2 Hour Event 2 Second Resolution
MWs
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
StateofCharge
Demonstration of wind smoothing a 18 MW wind farm with 4 MW - 10 min energy
storage.

12. 12
EES Selection Criteria
• Power Rating and Energy Capacity
• Round Trip Efficiency
• Service Life
– Cycle Life
– Calendar Life
• System Cost
– Cost per Unit Power ($/kW)
– Cost per Unit Energy ($/kWh)

13. Advanced Lead Acid
Lead-Acid batteries consist of two
electrodes: Lead and lead-dioxide
immersed in sulfuric acid.
Performance
measure
Cycle
Life
Energy
Efficiency
(%)
Price
Point
($/kWh)
Market
leader
1200 80 200
Best in class 2000 85 300
Lead Acid

14. Sodium based battery - NAS
Sodium-sulfur (NaS) batteries use
molten sodium and sulfur electrodes
separated by a ceramic electrolyte
Sodium Based
Performance
measure
Cycle
Life
Energy
Efficiency
(%)
Price
Point
($/kWh)
Market
leader
4000 70 500
Best in class 6000 85 750-1000

15. Li-ion Battery Technology
Li-ion battery uses graphite as the
anode material and LiFePO4 or LiCoO2
or Lithium titanate or lithium nickel
manganese cobaltate as the cathode.
Li-Ion Batteries
Performance
measure
Cycle
Life
Energy
Efficiency
(%)
Price
Point
($/kWh)
Market
leader
2000 90 400
Best in class 8000+ 95 600

16. Flow Battery Technology
Flow batteries use liquid electrolytes with fixed cells to store and regenerate power.
Various flow battery chemistries exist such as vanadium redox, zinc-bromine, iron -
chromium etc.
Performance
measure
Cycle
Life
Energy
Efficiency
(%)
Price
Point
($/kWh)
Market
leader
5000 60 500
Best in class 10000 70 1000
Flow Batteries

17. Future Advances in Energy Storage
PERFORMANCE
ENHANCEMENT
• Flow batteries boast of an
exceptional cycle lifetime but
have a much lower roundtrip
energy efficiency as
compared to lithium ion
batteries.
• Lead acid batteries have high
efficiency and low cost but
their cycle lifetime is very low
compared to other
technologies
INNOVATIVE materials and cell design improvements which can enhance the specific
properties of respective energy storage technologies will play a crucial role in making the
technologies attractive for rapid commercialization.

18. Key Trends in Energy Storage
18

19. Energy Storage Landscape 2016
* In addition Thermal storage, ultra capacitors and fuel cells are also part of energy storage ecosystem

20. A platform for scaling technically and financially sustainable microgrids.

21. Combined buying
power when dealing
with OEMs
Affordable electricity
for end consumer
Linking electricity to
economic development
of region
Better Channelizing
of Funds
Data analytics for better
energy management and
system modelling
Reporting services for
funding agencies and
microgrid developers
Scaling up of
Operations
Product innovation for
Bottom of Pyramid
Why Microgrid Initiative
for Campus & Rural Opportunities?
Database of existing &
potential microgrids and
efficient equipment

22. Policy Makers
Funding Agency
Communication
& Automation
Technology
Provider
Developers
Local
body
Habi
tants
Key Stakeholders in Off-grid and
Microgrid Rural Electrification
Habitants of un-electrified remote hamlets and villages are the most important stakeholders and their
aspirations and well-being are the key to viability of micro-grids.

23. Business and Value Proposition
System designed to monitor over 100,000
microgrids

24. Optimizing Microgrid design and
Improving life & efficiency

25. Suboptimal design & operations of Inverter & Batteries
can be optimized to improve economics
Power conversion at lower
efficiency
Inverters were found working at
lower efficiency by around 10.0%
in the sites visited by CES. Either
the inverters are less efficient than
that considered above or
probably, the battery charging
efficiency is 9% or 10% lower than
theoretical value. This is probably
due to hard sulphate formation in
battery plates, which are always
operating at low state of charge
and the absence of any
freshening/equalizing charge
regime.
Oversized plants
System build with 6 kW
of solar PV are
delivering less than 1 kW
of output through out the
day. This leads to poor
return on investment,
lower conversion
efficiency of the inverters
and idle battery capacity
which can lead to
incapability of the
storage to deliver deep
discharge during the
actual requirement.
Battery State-of-charge
• SoC read by inverter at Site A
was 77% and as confirmed by
Exide as per specific gravity
readings was 38%
• SoC read by inverter at Site
B was 85% and as confirmed by
Exide as per specific gravity
readings was 44%
Hence, during a sunny day the
power generated by plant was
almost zero as the inverter had
put batteries on float mode
reading SoC as 85%. But
unfortunately batteries were
only partially charged.

26. Microgrid Initiative for
Campus & Rural Opportunities (MICRO)
– Phase 1
26

27. Skills Development and
Integrating Microfinance for Economic Growth
Partnering with microfinance
institutions and other funding
agencies for supporting economic
development through Sustainable
anchor loads linked to village
economy.
We are organizing workshops through
industry academic collaborations for
skill development and sharing best
practices.
• 1st workshop held in December 2015.
• 4 regional workshops planned for
2016.

28. MICRO Team & Partners
Harsh
Thacker,
Project &
Stakeholder
Manager
Dr. Satish B
Agnihotri,
Chief
Advisor
Javed
Shaikh,
Technical
Manager
and Portal
Developer
Jyoti Deka,
Site
Inspection
and Load
Designing
Dr. Rahul
Walawalkar,
Thinker-in-
chief,
Chairman
Rajarshi Sen,
Battery and
System
Design
Expert
Vinay
Walimbe,
Progress
Monitoring
Vipul Pagrut,
Hardware
Engineer
A diverse team developed to achieve these initiatives.

29. Join IESA to learn more!
29
Customized Energy Solutions India Pvt. Ltd.
A 501, GO Square
Aundh - Hinjewadi Link Rd, Wakad
Pune, Maharashtra 411057 India
Phone: 91-20-32407682
info@ces-ltd.com
Customized Energy Solutions Ltd.
1528 Walnut Street, 22nd Floor
Philadelphia, PA 19102 USA
Phone: +1-215-875-9440
Fax: +1-215-875-9490
info@ces-ltd.com
Dr. Rahul Walawalkar
Executive Director, IESA &
President and MD, CES India
rahul@ces-ltd.com
US Cell: +1-516-639-5391
India Cell: +950-303-1765