Multiple Energy Storage Technologies are being developed & are maturing, Gensol did an analysis of 1635 Energy Storage Projects developed globally to come up with which technology has captured market share. The presentation also has multiple case studies.

1. GENSOL CONSULTANTS PVT. LTD
www.gensol.in
Globally Leading BESS Technologies-May 2017

2. Demand of Energy Storage Systems (ESS) & Uses
Gensol Group
1000 GW by 2030, when the total installed solar and wind capacity will be 5000 GW* Supply
and Demand side of the wholesale generation market:
Renewable integration - High intermittency of renewable energy making it difficult to
forecast and schedule for dispatches,
Large unmet energy demand & low energy access in rural areas
Frequency regulation and reductions of CO2 emissions.
Grid stabilisation and constrained transmission and distribution capacity.
*Source : REmap Analysis 2017

3. Types of ESS Technologies Present Worldwide
Gensol Group
Chemical Energy Storage Hydrogen Storage
Pumped Heat Electrical Storage
Pumped Hydro Storage
Liquid Air Storage
Diabatic/Adiabatic Compressed
Storage
Mechanical Energy Storage
Thermal Energy Storage Electrochemical Energy StorageThermal Hot Water Storage
Adsorption Storage
Electro-chemical
Double Layer
Capacitor Storage
Power Electronics
Capacitor Storage
Flow Battery
Lead Acid Battery
Lithium Ion Battery
Li-Metal Polymer
Li-Sulphur
Ni-Metal/Ni Cadmium
Na-Sulphur &
many more…
Source : European Association for Storage of Energy (EASE) 2017
Energy Storage Systems Technologies
Electrical Energy Storage

4. Development / Deployment of Various of ESS Technologies
Gensol Group
Analysis have been carved out for the various Globally installed ESS till May 2017 which includes operational, under
construction, contracted, announced, under-repair/offline & de-commissioned projects. Around 193.3 GW (approx.) ESS systems
of various technologies like mechanical, thermal, chemical storage systems have been installed worldwide; while some
technologies are under development stage.
Source : IEA Energy Storage Technology Roadmap 2014
Individual technologies are tailored for different applications
like demand charge reduction, backup power, or increasing
solar self-consumption etc. Li-Ion batteries (LIB) currently
dominating the market, but a diverse blend of battery
technologies is being deployed.
Mature TechnologyDeployment TimeResearch Development Demonstration
CapitalrequirementxTechnologyrisk
Flow batteries
Super capacitor
Adiabatic CAES
Pumped hydro
storage (PHS)
Flywheel (low speed)
Sodium-sulfur (NaS) batteries
Lithium-ion batteries
Compressed air energy
Storage (CAES)
Molten salt
Superconducting magnetic
energy storage (SMES)
Hydrogen
Synthetic natural gas
Legend
Mechanical storage
Electro-chemical storage
Thermal storage
Electrical storage
Chemical storage

5. Categorization of ESS Based on Application vs Discharge Time
ESS has been categorized based on power ratings and
discharge times. Based on this, each technology has its
own characteristics and useful applications; installed
globally.
Source: ESRU, University of Starthclyde
http://www.esru.strath.ac.uk/EandE/Web_sites/14-15/Industrial_autonomy/2_1_technology_options.html
Bull Power
Management
Transmission & Distribution
Grid Support
Reserve & Response
Services
SYSTEM POWER RATING, MODULE SIZE
DISCHARGETIMEATRATEDPOWER
1kW 10kW 100kW 1MW 10MW 100MW 1GW
SecondsMinutesHours
KEY
Types of Storage
Hydrogen-related
Mechanical
Electrochemical
Electrical
Thermal
Li-ion Battery
High-Enegy
Supercapacitors
Nickel Cadium Battery
Nickel Metal Hydride Battery
Flywheels
High-Power Supercapacitors
Super Conducting
Magnetic Energy Storage
Lead Acid Battery
Cryogenic Energy Storage
Sodium-Sulphur Battery
Advanced Lead-Acid Battery
Hydrogen & Fuel Cells
Flow Batteries
Pumped Hydro
Power Storage
Compressed Air
Enegy Storage
Gensol Group
+
_

6. Global Spread of ESS Projects till May 2017
Gensol Group
Electro-chemical
60.7%
Electro-mechanical
4.2%
Hydrogen Storage
0.8%
Liquid Air Energy
Storage
0.1%
Pumped Hydro Storage
21.5%
Thermal Storage
12.6%
Number of ESS Projects as on May 2017
Electro-chemical
Electro-mechanical
Hydrogen Storage
Liquid Air Energy
Storage
Pumped Hydro
Storage
Thermal Storage
Evaluation has been carried out by Gensol, around 1635 projects of ESS are available globally which includes
operational/under-repair/offline/de-commissioned, announced, contracted & under-construction projects for various field of
applications as on May 2017. Out of all technologies, highest projects of Electro-Chemical Storage System (ECSS) stands 1st
contributing 60.7% (993) of installed systems followed by Pumped Hydro Energy Storage (PHES) with 21.5% (352).

7. Installed Capacity of ESS Systems Worldwide as on May 2017
Gensol Group
Electro-chemical
1.6%
Electro-mechanical
1.3%
Hydrogen Storage
0.01%
Liquid Air Energy
Storage
0.003%
Pumped Hydro
Storage
95.0%
Thermal Storage
1.8%
Capacity Wise Installed ESS Technologies as on May 2017
Electro-chemical
Electro-mechanical
Hydrogen Storage
Liquid Air Energy
Storage
Pumped Hydro Storage
Thermal Storage
Pumped Hydro Storage (‘Mature Technology’) is the leading ESS technology (Capacity ) with 183.8 GW Out of total 193.3 GW
installed capacity, followed by Thermal Storage with 3.6 GW, Electro-Chemical Storage with 3.2 GW & Electro-Mechanical storage
with 2.6 GW which are under ‘Deployment Stage’ . Liquid Air & Hydrogen Storage Systems contributes the least share of 0.02
GW (‘Development Stage’). PHES technology is relatively simple storage way, cost-effective, provides plant life of 50-100 years,
grid stability, reliable & quality power supply.

8. Sub-Categories of Installed ESS Technologies – (1/4)
Gensol Group
Comparing to overall PHES, the
Open Loop PHES accounts the
highest installed capacity of 92.4%
having advantage of highest power
potential, longest life expectancy &
easily available natural free flowing
water source. In Closed loop
systems, water resource for initial
charge & make up water to replace
losses from evaporation leakage is
required. However, these are
preferred because of the fewer
environmental impacts.
Similarly, Molten Salt Storage have
highest installed capacity of 2.7 GW
(84.3% of overall Thermal Storage
System)
Types of Thermal Storage System
Types of Pumped Hydro Storage System
7955.8
169843.5
6000.0
1.5
0 50000 100000 150000 200000
Closed-loop Pumped Hydro Storage
Open-loop Pumped Hydro Storage
Pumped Hydro Storage
Seawater Open-loop Pumped Hydro Storage
Installed Capacity in MW
Pumped Hydro Energy Storage(PHES) Capacity
137.2
0.1
129.8
112.4
2751.9
491.4
0 500 1000 1500 2000 2500 3000
Chilled Water Thermal Storage
Concrete Thermal Storage
Heat Thermal Storage
Ice Thermal Storage
Molten Salt Thermal Storage
Thermal Storage
Installed Capacity in MW
Thermal Energy Storage System Capacity

9. Sub-Technologies of Installed ESS Technologies–(2/4)
Gensol Group
Despite of other developed
technologies, various ECSS are
advancing at a good pace.
Of which, Li-Ion Batteries (LIB) are
leading the whole market scenario of
BESS since last few years due to its
high energy density, low
maintenance, self discharge & other
positive aspects; leading with 60.0%
of BESS share capacity wise.
Types of Electro-chemical Storage System
1939.5
323.3
197.9
186.6
112.8
84.9
79.3
75.5
58.5
43.1
36.5
32.0
23.6
22.5
19.6
17.9
16.2
9.5
0 500 1000 1500 2000 2500
Lithium-ion Battery
Electro-chemical
Sodium-sulfur Battery
Lithium Iron Phosphate Battery
Lithium Nickel Manganese Cobalt Battery
Lead-acid Battery
Electro-chemical Capacitor
Vanadium Redox Flow Battery
Zinc Bromine Flow Battery
Advanced Lead-acid Battery
Lithium Ion Titanate Battery
Nickel-cadmium Battery
Sodium-nickel-chloride Battery
Lead Carbon Battery
Zinc Air Battery
Other
Valve Regulated Lead-acid Battery
Lithium Polymer Battery
Installed Capacity in MW
Electrochemical Technology Type Capacity

10. Sub-Technologies of Installed ESS Technologies–(3/4)
Gensol Group
From the evaluation performed by
Gensol, Flywheel Energy Storage
Systems (FESS) and In-Ground
Compressed Air Storage systems
(CAES) are deployed with 37.1% &
36.1% shares of mechanical storage
systems respectively.
Adiabatic Compressed Air Storage
are under development stage,
contributing about 0.02% till date.
Presently, Flywheel and Battery ESS are operating in the competitive services in RE market – providing 10 times faster
and more accurate response to a power dispatcher’s signals compared to power turbine generators.
Types of Electro-mechanical Storage System
0.5
0.7
972.1
50.0
947.0
202.0
431.0
0.4
11.1
2.0
0 200 400 600 800 1000 1200
Adiabatic Compressed Air Storage
Compressed Air Storage
Flywheel
Gravitational Storage
In-ground Compressed Air Storage
In-ground Iso-thermal Compressed Air
In-ground Natural Gas Combustion…
Liquid Air Energy Storage
Modular Compressed Air Storage
Modular Iso-thermal Compressed Air
Installed Capacity in MW
Electro-mechanical Energy Storage Capacity

11. Sub-Technologies of Installed ESS Technologies–(4/4)
Gensol Group
Liquid Air Energy Storage
(LAES) or Cryogenic Energy
Storage (CES) and
Hydrogen Energy storage
Systems (HESS) are
upcoming technologies, with
0.1% & 0.8% resp. of overall
ESS market as on May 2017.
Despite low efficiency (30-40%), HES systems are evolving due to the much higher
storage capacity as compared to batteries (small scale) or pumped hydro and CAES (large
scale).
Similarly, LAES systems have long lifespan of 30+ years, resulting in low technology risk and is
a large scale energy storage technology that can be located at the point of demand.
18.5
0 10 20
Hydrogen Storage
Installed Capacity in MW
Hydrogen Energy Storage Hydrogen
Storage
5.4
0 2 4 6
Liquid Air Energy
Storage
Installed Capacity in MW
Liquid Air Energy Storage Capacity

12. Case Studies of ESS Technologies (1/6)
(1) Pumped Hydro Energy Storage
Gensol Group
Location – Purulia, West Bengal, India
Technology Type
Open Looped PHES
Owner (3rd Party Owned)
Utility
West Bengal State Electricity
Dis. Company Ltd(WBSEDCL)
About the Project
Name of Project – Purulia Pumped Storage Project
Duration
4-6 Hrs.
Status of Project
Operational
Date of Commissioning
1st February 2008 Application
Frequency variation, grid
stability, meets peak
demand, Electric Energy Time
Shift
Source- http://www.energystorageexchange.org/projects/480
This project generates 900 MW power instantly by discharging stored water from Upper dam to
Lower Dam through reversible pump-turbine and generator motor The project cost of Rs 2,953
crore is funded as a loan assistance from the Japan Bank for International Cooperation. The
entire Power house was constructed under the hills. HCC- L&T JV carried out a major portion of
the project under contract from M/s TAISEI, one of the Japanese Contractors. HVAC System for
the entire project was carried out by Aircon Group under sub-contract from HCC- L&T JV."

13. Case Studies of ESS Technologies (2/6)
(2). Thermal Energy Storage
Gensol Group
Location - Maria Elena (Antofagasta), Chile
Technology Type
Molten Salt 2-Tank Indirect
Owner (3rd Party Owned)
Grupo Ibereolica (100%)
Utility/Project Type
Commercial
About the Project
Name of Project Pedro de Valdivia
Duration
10.50 Hrs.
Status of Project
Operational
Date of Commissioning
1st January 2015
Application
Renewable Capacity firming
Renewable Energy Time Shift
The Concentrating Solar project (Parabolic trough), located at Maria Elena in the
Antofagasta region, is a 360 MW plant divided in two phases (I and II) which in turn are
divided into two 90 MW units. The plant will use parabolic trough technology with
thermal storage. The expected generation is up to 2.108 GWh per year.

14. Case Studies of ESS Technologies (3/6)
(3). Electro-Chemical Energy Storage
Gensol Group
Location - Western Texas, US
Technology Type
Lithium Ion Battery (LIB)
Owner (Utility Owned)
Duke Energy (100%)
Utility/Project Type
Commercial
About the Project
Name of Project - Notrees Battery Storage Project
Duration
0.67 Hrs.
Status of Project
Operational
Date of Commissioning
1st January 2013
Application
Energy Time Shift, Freq. Regulation,
Renewables Capacity Firming
http://windcoalition.org/duke-energy-build-los-vientos-v-wind-power-project-texas/
http://www.sandia.gov/ess/docs/pr_conferences/2011/3_Ratnayake_Notrees.pdf
The project demonstrates how energy storage and power storage technologies can help wind
power systems address intermittency issues by building a 36 MW/24 MWh turnkey energy
storage and power management system capable of optimizing the delivery of energy, in
addition to providing regulation service in the ERCOT market. The project is supported by a
U.S. DOE Office of Electricity ARRA grant.

15. Case Studies of ESS Technologies (4/6)
(4). Electro-Mechanical Energy Storage
Gensol Group
Technology Type
Flywheel
Owner (3rd Party Owned)
Spindle Grid Regulation, LLC
Beacon Power, LLC
Utility/Project Type
Pennsylvania Power and
Light (PPL)/Commercial
About the Project
Duration
0.25 Hrs
Status of Project
Operational
Date of Commissioning
30th July 2014
Application
Frequency RegulationSource :http://beaconpower.com/
Location - Hazle Township, Pennsylvania, United States
20 MW plant is comprised of 200 Beacon Power Series 400 flywheels that provides frequency
regulation services to grid operator PJM Interconnection. They recycle energy from the grid in
response to changes in demand and grid frequency. When generated power exceeds load, the
flywheels store the excess energy. When load increases, the flywheels return the energy to the
grid. The flywheels are rated at 0.1 MW and 0.025 MWh, for a plant total of 20.0 MW and 5.0
MWh of frequency response.
Name of Project - Beacon Power

16. Case Studies of ESS Technologies (5/6)
(5). Hydrogen Energy Storage
Gensol Group
Location - Mainz, Rheinland-Pfalz, Germany
Technology Type
Hydrogen Storage
Owner (Utility Owned)
Spindle Grid Regulation, LLC
Beacon Power, LLC
Utility/Project Type
Pennsylvania Power and Light
(PPL)/Commercial
About the Project
Name of Project - Energiepark Mainz
Duration
13.0 Hrs.
Status of Project
Operational
Date of Commissioning
2nd July 2015
Application
Demand Response Load Following,
Ramping Renewables, Capacity
Firming Stationary, Transmission
Upgrade Deferral, Transmission
Congestion
Source- http://www.energieparkmainz.de/projekt/bilder/
Energiepark Mainz is the world's first multi-MW Polymer Electrolyte Membrane (PEM)
electrolysis based power-to-gas project. It features about 6 MW of peak capacity and 4 MW
continuous capacity. The produced hydrogen is compressed by an ionic compressor, stored
onsite and filled into trailers and injected into the natural gas grid.

17. Case Studies of ESS Technologies (6/6)
(6). Liquid Air Energy Storage
Gensol Group
Location - Bury, Lancashire, United Kingdom
Technology Type
Hydrogen Storage
Owner (Customer Owned)
Viridor, UK
Utility/Project Type
Electricity North West/Commercial
About the Project
Name of Project - Highview Power Storage
Duration
3.0 Hrs.Status of Project
Operational
Date of Commissioning
1st August 2016
Application
Electric Supply Reserve Capacity - Non-
Spinning Frequency Regulation,
Transmission Congestion Relief,
Transmission Support, Voltage Support
Congestion
Source : http://www.highview-power.com/pre-commercial-laes-technology-demonstrator/
In addition to providing energy storage, the LAES technology plant converts low grade waste
heat from the onsite landfill gas engines to electrical power. The project will operate for at least
one year and will demonstrate LAES providing a number of grid balancing services in the UK,
including Short Term Operating Reserve (STOR), Secondary frequency response testing, Triad
Avoidance (supporting the grid during the winter peaks) and also testing for the US regulation
market.

18. Comparison of All BESS Technologies : ESS Vs EV
Gensol Group
With the evolving demands of Grid stabilisation
and RE integration etc., to maintain uninterrupted
power supply in various field of applications, ESS
are at high peaks. Further, to make vehicles fuel
free in aim of reducing CO2, GHG emissions, use
of Electrical vehicles (EVs) has bloomed in the
energy market.
Source : Energy Storage Toolkit 2012
ESS –Energy Storage System EV – Electric Vehicle
Different energy storage technologies
Have been compared in this respect for
ESS & EV applications :
Energy storage technology ESS EV
Li-ion
Ultracapacitor
Fuel cells
Lithium air
Lead-acid
NiMH
Lithium sulphur
Sodium sulphur
Metal air
Flow batteries
Flywheel
Molten salt
Hydropower
SMES
CAES
Source: Dalwa
Note: = Not usable






= Excellent = Good = Usable


19. Key Highlights – ESS Technologies
Gensol Group
Key Highlights
Pumped hydro energy storage systems are leading energy storage technology with 95.0% of the installed capacity
followed by thermal energy storage (1.8%); has step-into a stabilized energy market.
Battery ESS with 1.6% and Flywheel with 0.5% of installed capacity are operating in the competitive services in RE
market.
Liquid air and hydrogen energy storage systems are upcoming technologies, with 0.12% & 0.80% resp. of overall
ESS market as on May 2017.
It has been observed from the evaluation that since last few years various new BESS technologies are ruling the
market and many more are coming out. Also, BESS relies on chemical properties and thus rapid energy density
enhancement in chemical technologies/products in the electronics industry
All BESS technologies, Lithium-Ion Batteries are being preferred and overtook 60.0% of the BESS market capacity
wise over other technologies due to its higher energy density.
However, upcoming technologies promises to give optimized power output at lower cost for long term services of
BESS.

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anmoljaggi@gensol.in
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Development
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21. Gensol is one of the leading consultants and system integrators for Solar Power Plants. We boast of a portfolio of over 6000 MW of Solar Photovoltaic Plants. Gensol is also a channel
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