On Thursday 19 November 2015, the British Embassy in Paris hosted a second trilateral workshop with French, German and British delegates from the research, government and business sectors to discuss the importance of energy storage.

1. Energy Storage –
Resaerch-Based Demo Projects
In Germany
Andreas Hauer
TRILATERAL ENERGY STORAGE WORKSHOP, 19 NOVEMBER
BRITISH AMBASSADOR’S RESIDENCE, PARIS

2. Energy Storage –
Basic Definitions

3. Definitions „Energy Storage“
What is energy storage?
An energy storage system can take up energy and deliver it at a later point in
time. The storage process itself consists of three stages: The charging, the
storage and the discharging. After the discharging step the storage can be
charged again.
Charging Storage Discharging

4. Definitions „Energy Storage“
What is actually stored?
The form of energy (electricity, heat, cold, mechanical energy, chemical
energy), which is taken up by an energy storage system, is usually the one,
which is delivered.
However, in many cases the charged type of energy has to be transformed
for the storage (e.g. pumped hydro storage or batteries). It is re-transformed
for the discharging. In some energy storage systems the transformed energy
type is delivered (e.g. Power-to-Gas or Power-to-Heat).
h

5. Relation between energy storage systems and their applications
The technical and economical requirements for an energy storage system are
determined by its actual application within the energy system. Therefore any
evaluation and comparison of energy storage technologies is only possible
with respect to this application.
The application determines the technical requirements (e.g. type of energy,
storage capacity, charging/discharging power,…) as well as the economical
environment (e.g. expected pay-back time, price for delivered energy,…).
Definitions „Energy Storage“
Electrolysis Hydrogen

6. Energy Storage –
Technologies

7. Energy Storage Technologies
Electrical Energy Storage
Thermal Energy Storage
Chemical Energy Storage

9. Energy Storage –
Applications

10. Constant Supply Fluctuating Supply
Matching Supply and Demand

11. „Storage of Power“ „Storage of Energy“
e.g. Power Reserve e.g. Peak Shaving /
Dispatchable Load
Difference between Power & Energy
Power
Power
Seconds - Minutes Hours – Days

12. Integration of Renewable Electricity
• Grid Stability
 Frequency regulation
 Voltage support
 T&D congestion relief
 Black start
• Grid balancing
 Fast power reserve
 Peak shaving
 Self-consumption, Off-grid
• Demand Side Integration
 Dispatchable Load
 Power-to-Gas
 Power-to-Heat
Integration of Renewable Thermal
Energy
• Concentrated Solar Power
• Solar-thermal Process Heat
• Solar-thermal Heating & Cooling
Industrial Processes
• Waste Heat Utlization
• Recuperation of Mech. Energy
Buildings
• Heating & Cooling
 Day/Night-Balancing
 Summer/Winter-Balancing
Electricity Production
• Fossil Thermal Power Plants
• Heat Utilization of CHP
• …
Mobility
• Propulsion
• Heating / Air Conditioning
Renewable Energies Energy Efficiency

13. Integration of Renewable Electricity
• Grid Stability
 Frequency regulation
 Voltage support
 T&D congestion relief
 Black start
• Grid balancing
 Fast power reserve
 Peak shaving
 Self-consumption, Off-grid
• Demand Side Integration
 Dispatchable Load
 Power-to-Gas
 Power-to-Heat
Integration of Renewable Thermal
Energy
• Concentrated Solar Power
• Solar-thermal Process Heat
• Solar-thermal Heating & Cooling
Industrial Processes
• Waste Heat Utlization
• Recuperation of Mech. Energy
Buildings
• Heating & Cooling
 Day/Night-Balancing
 Summer/Winter-Balancing
Electricity Production
• Fossil Thermal Power Plants
• Heat Utilization of CHP
• …
Mobility
• Propulsion
• Heating / Air Conditioning
EES – TES – EES/TES/CES
Renewable Energies Energy Efficiency

14. Some examples for Demo-Projects
in Germany

15. Integration of Renewable Electricity
• Grid Stability
 Frequency regulation
 Voltage support
 T&D congestion relief
 Black start
• Grid balancing
 Fast power reserve
 Peak shaving
 Self-consumption, Off-grid
• Demand Side Integration
 Dispatchable Load
 Power-to-Gas
 Power-to-Heat
Integration of Renewable Thermal
Energy
• Concentrated Solar Power
• Solar-thermal Process Heat
• Solar-thermal Heating & Cooling
Industrial Processes
• Waste Heat Utlization
• Recuperation of Mech. Energy
Buildings
• Heating & Cooling
 Day/Night-Balancing
 Summer/Winter-Balancing
Electricity Production
• Fossil Thermal Power Plants
• Heat Utilization of CHP
• …
Mobility
• Propulsion
• Heating / Air Conditioning
Renewable Energies Energy Efficiency

16. • Within the building 25.600 Lithium-Manganoxide
cells are installed
• 5 medium voltage transformers are connecting the
storage to the grid
5 MW battery power plant can replace a conventional
50 MW turbine due to its accurate control potential
• 5 MW/5 MWh
• Lithium-Ion
• Primary control
• Option to extend to
10 MW/10 MWh
• Commissioned: 06/2014
Schwerin Battery Park
Batteries react accurate and fast to
frequency changes

17. Island Solution „Smart Region Pellworm“

18. Pilot project for H2-elektrolysis and storage at
Mainz, Germany
Partner: Stadtwerke Mainz, Linde, Siemens and
Hochschule RheinMain
• Siemens PEM elektrolyser peak power 6 MW
• Linde ionic compressor for flexible and energy
efficienten operation
• H2 pressure storage ~1000 kg (~33 MWh)
• H2-Trailer filling station
• H2 feed-in into the natural gas network
• Electricity supply from different sources: Wind, power
reserve, spot market…
Goals:
• Operation of local electricity grid
• Testing and operation experiences of
components and system
• Intelligent controlling and market
integrationSteuerung & Marktintegration
Pilot Project „Energiepark Mainz“

19. © ZAE Bayern
Solar District Heat, Munich
• 13 Buildings
• 320 Appartements
• 30.400 m² (floor area)
• 2.900 m² Solar Collectors
• Absorption driven by
District Heat
• Seasonal Storage (Summer/Winter)
• Hot Water Storage
• Volume 6.000 m³
• Temperatures 10°C - 95°C
SystemStorage

20. © ZAE Bayern
Mobile Heat Storage for Waste Heat
Utilization
© ZAE Bayern
• Thermochemical heat storage (adsorption)
• Charging temperature up to 300 °C
• Discharging temperature adjustable
• Waste heat from a waste incineration plant for an industrial
drying process (distance 7km)
• Storage capacity 4 MWh, thermal power 0.5 MW

21. Flywheels for Energy Efficiency
Properties:
• High speed rotor with max. 45.000 U/min.
• 1 flywheel 22 kW, up to 28 flywheels in one container
• Ideal cycle time some seconds to 30 minutes
Subway Trains or Trams:
• Break energy can be recovered and used for other trains or stations
electricity demand
• Storage for some minutes for later use
• Avoiding voltage peaks by storage
Example:
Two breaking subway trains deliver electricity for one train to accelerate!
Container Lifting
• By diesel engines (high fuel
consumption) or electriccal
motors (high power peaks)
• Storage at lowering for next
lifting
• Fuel or electricity savings and
reduction of power price

22. Technology Comparison (?)

23. Storage
technology
Storage
Mechanis
m
Power Capacity
Storage
Period
Density Efficiency Lifetime Cost
MW MWh time kWh/ton kWh/m3 % # cycles $/kW $/kWh
¢/kWh-
delivere
d
Lithium Ion
(Li Ion)
Electro-
chemical
< 1,7 < 22 day - month 84 - 160 190 - 375 0,89 - 0,98
2960 -
5440
1230 -
3770
620 -
2760
17 - 102
Sodium Sulfur
(NAS) battery
Electro-
chemical
1 - 60 7 - 450 day 99 - 150 156 - 255 0,75 - 0,86
1620 -
4500
260 -
2560
210 -
920
9 - 55
Lead Acid
battery
Electro-
chemical
0.1 -
30
< 30 day - month 22 - 34 25 - 65 0,65 - 0,85
160 -
1060
350 -
850
130 -
1100
21 - 102
Redox/Flow
battery
Electro-
chemical
< 7 < 10 day - month 18 - 28 21 - 34 0,72 - 0,85
1510 -
2780
650 -
2730
120 -
1600
5 - 88
Compressed air
energy storage
(CAES)
Mechanical 2 - 300 14 - 2050 day -
2 - 7 at
20 - 80 bar
0,4 - 0,75
8620 -
17100
15 -
2050
30 - 100 2 - 35
Pumped hydro
energy storage
(PHES)
Mechanical
450 -
2500
8000 -
190000
day - month
0,27 at
100m
0,27 at
100m
0,63 - 0,85
12800 -
33000
540 -
2790
40 - 160 0,1 - 18
Hydrogen Chemical varies varies indefinite 34000
2,7 - 160 at
1 - 700 bar
0,22 - 0,50 1
384 -
1408
- 25 - 64
Methane Chemical varies varies indefinite 16000 10 at 1 bar 0,24 - 0,42 1 - - 16 - 44
Sensible
storage - Water
Thermal < 10 < 100 hour - year 10 - 50 < 60 0,5 -0,9 ~5000 - 0,1- 13 0,01
Phase change
materials (PCM)
Thermal < 10 < 10 hour - week 50 - 150 < 120 0,75 - 0,9 ~5000 - 13 - 65 1,3 - 6
Thermochemic
al storage
(TCS)
Thermal < 1 < 10 hour - week 120 -250 120 - 250 0,8 - 1 ~3500 - 10 - 130 1 - 5
Comparison of Energy Storage
Technologies
Comparison of storage technologies is difficult.
There is a strong influence of the actual application on
the storage properties!

24. Storage
technology
Storage
Mechanis
m
Power Capacity
Storage
Period
Density Efficiency Lifetime Cost
MW MWh time kWh/ton kWh/m3 % # cycles $/kW $/kWh
¢/kWh-
delivere
d
Lithium Ion
(Li Ion)
Electro-
chemical
< 1,7 < 22 day - month 84 - 160 190 - 375 0,89 - 0,98
2960 -
5440
1230 -
3770
620 -
2760
17 - 102
Sodium Sulfur
(NAS) battery
Electro-
chemical
1 - 60 7 - 450 day 99 - 150 156 - 255 0,75 - 0,86
1620 -
4500
260 -
2560
210 -
920
9 - 55
Lead Acid
battery
Electro-
chemical
0.1 -
30
< 30 day - month 22 - 34 25 - 65 0,65 - 0,85
160 -
1060
350 -
850
130 -
1100
21 - 102
Redox/Flow
battery
Electro-
chemical
< 7 < 10 day - month 18 - 28 21 - 34 0,72 - 0,85
1510 -
2780
650 -
2730
120 -
1600
5 - 88
Compressed air
energy storage
(CAES)
Mechanical 2 - 300 14 - 2050 day -
2 - 7 at
20 - 80 bar
0,4 - 0,75
8620 -
17100
15 -
2050
30 - 100 2 - 35
Pumped hydro
energy storage
(PHES)
Mechanical
450 -
2500
8000 -
190000
day - month
0,27 at
100m
0,27 at
100m
0,63 - 0,85
12800 -
33000
540 -
2790
40 - 160 0,1 - 18
Hydrogen Chemical varies varies indefinite 34000
2,7 - 160 at
1 - 700 bar
0,22 - 0,50 1
384 -
1408
- 25 - 64
Methane Chemical varies varies indefinite 16000 10 at 1 bar 0,24 - 0,42 1 - - 16 - 44
Sensible
storage - Water
Thermal < 10 < 100 hour - year 10 - 50 < 60 0,5 -0,9 ~5000 - 0,1- 13 0,01
Phase change
materials (PCM)
Thermal < 10 < 10 hour - week 50 - 150 < 120 0,75 - 0,9 ~5000 - 13 - 65 1,3 - 6
Thermochemic
al storage
(TCS)
Thermal < 1 < 10 hour - week 120 -250 120 - 250 0,8 - 1 ~3500 - 10 - 130 1 - 5
Application: Long Term Storage

25. Transport
~ 90 %
~ 62%
Total:
Storage
~ 90 %© U. Stimming, TUM
Efficiency:
Hydrogen:
Electrolysis
~ 85 %
Compression
~ 90 %
Fuel: Overall Efficiency 60 %
Electricity: Overall Efficiency 30 %
Heating: Overall Efficiency 60 %
Application: Long Term Storage

26. Heat Pump
~ 300 %
Efficiency:
~ 225 %
Total
Hot Water:
Storage
~ 75 %
© ZAE Bayern
Fuel: not possible!
Electricity: not possible!
Heating: Overall Efficiency 225 %
Application: Long Term Storage

27. Important:
• Look at the whole efficiency chain!
• Take the „value“ of the stored energy
(„exergy“!) into account!
• Take the final energy demand into account!
• Also Power-to-Heat / Power-to-Cold is an
option!
• Try to identify the most suitable technology for
the application!
Comparison of Energy Storage
Technologies

28. Conclusions

29. A large number of different energy storage technologies is
available or subject to R&D at the moment
A large number of different applications of energy storage will
come up in our future energy systems
Energy storage technologies can only be evaluated and compared
- technically and economically - within an actual application
Conclusions
The final energy demand and the overall efficiency of the energy
storage system has to be taken into account, when assigning
storage technologies to storage applications

30. Thank you very much for your attention!