1. Stationary Battery Storage Systems
Dirk Magnor
Chair for Electrochemical Energy Conversion and Storage Systems (Univ.-Prof. Dirk Uwe Sauer)
Institute for Power Electronics and Electrical Drives
RWTH Aachen University
Stationary Battery Storage Systems
- Technology Overview, Cost Calculation and Application Examples -

2. Definition of a Storage System
Stationary Battery Storage Systems

3. Definition of a Storage System – Pumped Hydro Storage
Stationary Battery Storage Systems

4. What Size do Storage Systems Have?
Pumped Hydro Storage: 1 m3 at a hight of 360 m for 1 kWh
Source:
Stationary Battery Storage Systems

5. Definition of a Storage System – Battery Storage
Stationary Battery Storage Systems

6. What Size do Storage Systems Have?
Battery Storage:
20 ft container can house 1 MWh / 1 MW lithium ion batteries
Approx. 4 times the size for same amount of lead-acid or redox-flow batteries
PV battery systems have approx. the size of a fridge
Stationary Battery Storage Systems

7. Example for Storage Dimensions
Most modern class of container ships can carry approx. 15,000 containers (400 m x 56 m base area)
Stationary Battery Storage Systems

8. ≡ Example for Storage Dimensions
Most modern class of container ships can carry approx. 15,000 containers (400 m x 56 m base area)
Completely loaded with battery containers, this equals a capacity of 15 GWh / 15 GW (all German pumped hydro plants: 60 GWh / 6 GW) ≡
Energy
Stationary Battery Storage Systems

9. ≡ Example for Storage Dimensions
Most modern class of container ships can carry approx. 15,000 containers (400 m x 56 m base area)
Completely loaded with battery containers, this equals a capacity of 15 GWh / 15 GW (all German pumped hydro plants: 60 GWh / 6 GW) ≡
Power
Stationary Battery Storage Systems

10. Outline Battery Technology Overview
Aspects of Battery Cost Calculation
Application Examples
Stationary Battery Storage Systems

11. Lead Acid Batteries Stationary Battery Storage Systems Parameter
Efficiency
80 % – 85 %
Calendar Life
5 – 15 years
Cycle Life
500 – 2.000
Specific Energy Cost
80 – 200 €/kWh
Specific Power Cost
100 – 200 €/kW
SWOT
Strengths
High availability
Experience with large systems
Weaknesses
Low cycle life
Space ventilation mandatory
Oportunities
Many manufacturers worldwide
Cost reduction potentials
Threads
Limited reservoirs of lead
Competing with lithium ion batteries
Sources: Varta, Hoppecke Baterrien
Stationary Battery Storage Systems

12. Lithium Ion Batteries Stationary Battery Storage Systems Parameter
Efficiency
90 % – 95 %
Calendar Life
5 – 20 years
Cycle Life
1.000 – 5.000
Specific Energy Cost
200 – 500 €/kWh
Specific Power Cost
100 – 200 €/kW
SWOT
Strengths
Long lifetimes, high efficiencies,
High energy density
Weaknesses
High cost
Intrinsic safety
Oportunities
High cost reduction potentials
Threads
Lithium reservoirs limited to few countries
Sources: Saft, Kokam, GS YUASA
Stationary Battery Storage Systems

13. High Temperature Batteries
Parameter
Efficiency
82 % – 91 %
Calendar Life
15 – 20 years
Cycle Life
5.000 –
Specific Energy Cost
250 – 500 €/kWh
Specific Power Cost
100 – 200 €/kW
SWOT
Strengths
Long lifetimes, existing systems
Cheap raw materials (NaS)
Weaknesses
Thermal losses
High operation temperatures
Oportunities
Expiring patents
Availability of raw materials
Threads
Few manufacturers
Quelle: NGK, MES-DEA
Stationary Battery Storage Systems

14. Redox Flow Batteries (Vanadium)
Parameter
Efficiency
60 % – 74 %
Calendar Life
10 – 15 years
Cycle Life
>
Specific Energy Cost
150 – 400 €/kWh
Specific Power Cost
100 – 200 €/kW
SWOT
Strengths
Power and energy capacities independently scalable, high cycle life
Weaknesses
System complexity
High maintenance cost
Oportunities
Expiring patents
Threads
Vanadium is rare material
Quelle:
Stationary Battery Storage Systems

15. Redox Flow Batteries (Vanadium) – Functional Principle
Stationary Battery Storage Systems

16. Definition of a Storage System - Redox Flow Battery
Stationary Battery Storage Systems

17. Redox Flow Batteries (Vanadium)
Parameter
Efficiency
60 % – 74 %
Calendar Life
10 – 15 years
Cycle Life
>
Specific Energy Cost
150 – 400 €/kWh
Specific Power Cost
100 – 200 €/kW
SWOT
Strengths
Power and energy capacities independently scalable, high cycle life
Weaknesses
System complexity
High maintenance cost
Oportunities
Expiring patents
Threads
Vanadium is rare material
Source:
Stationary Battery Storage Systems

18. Battery Technologies – Interim Conclusion
Lead acid batteries
Lithium ion batteries
NiCd batteries
High temperature batteries (NaS, NaNiCl2)
Redox flow batteries
Currently dominating technologies
for decentralized PV battery systems
Technologically viable, but not to be
expected to large extent
Application especially for larger
systems feasible; market not
stimulated through small systems‘
sales
Stationary Battery Storage Systems

19. Cost Calculation Application parameters power [kW] Technology
specific power cost
[€/kW]
efficiency [%] self discharge [%/d]
energy [kWh]
cycles [#/d]
energy storage cost
[€ct/kWh] annuity method
specific energy cost
[€/kWh]
maximum depth
of discharge (DOD)
[%]
electricity cost [€ct/kWh]
system lifetime [a]
maintenance & repair [%/a]
cycle DOD [#]
capital cost [%]
Stationary Battery Storage Systems

20. Project Example – M5Bat
Goal: Construction and operation of a 5 MW / 5 MWh hybrid BESS in the reserve market with x Li: NMC/LMO and LFP/LTO 2 x Pb: OSCM and VRLA NaNiCl
Budget: 12.5 Mio. € total
6.5 Mio. € public funding

21. Applications – Primary Control Reserve (PCR)
Frequency [Hz]
Stationary Battery Storage Systems

22. Primary Control Reserve (PCR) – Load Profile
72 % of the time no load (dead band)
Activation nearly symmetrical pos. and neg. reserve – not quite
Maximum demand in 3 months 70 % of nominal power rating
Activation of > 25 % of nominal power in 0,36 % of the time  15,4 hours per year
Activation of > 50 % of nominal power in 0,0036 % of the time  8,5 minutes per year
Data 3,5 months cleaned data
> 25 %
25 % <
> 50 %
50 % <
Stationary Battery Storage Systems

23. Applications - Secondary Control Reserve (SCR)
Market volume in Germany:
Positive SCR MW
Negative SCR MW
267 M€ in 2012 (BNetzA)
Period of supply min. 4 h (4 MWh per MW)
Potential earnings (ideal) 200 k€ / MW = 50 k€ / MWh
Invest MW-battery system 2015 ca. 550 k€ / MWh
Annuity (550 k€; 12 years, 8 %) = 68 k€ / MWh
Plus operation cost and electricity purchase
 Currently, batteries can not provide SCR economically
 Viable approx
Traded seperately
Stationary Battery Storage Systems

24. Prospective Storage Markets
Control Reserve
EV / PHEV
PV home storage
Stationary Battery Storage Systems

25. Why Decentrelized Storage?
Data: BMU, EEG 2013 und BMWi Energiedaten
B.Burger, Fraunhofer ISE, Stand
PV reimbursement German EEG
Households
Industry
Increasing electricity cost + PV cost
Increasing margin for storage operation
Dependent on cost for generation, electricity purchase, storage
Storage
Storage
Stationary Battery Storage Systems

26. Conclusion – Take Home Messages
Different applications need different storage solutions
Batteries support short to medium term storage
For each application load profiles need to be evaluated to select the right battery
Large battery capacities will be available in the electricity grid from:
Increasing numbers of electrified vehicles
PV battery systems
Multiple use of storage systems can open markets earlier and improve economics of battery storage
Stationary Battery Storage Systems

27. Thank you very much for your attention.
Contact Details:
Dirk Magnor
Stationary Battery Storage Systems

28. Primary Control Reserve (PCR) – SOC Profile
Operational strategy for compensation of losses necessary (slow and low power)
Time share at given SOC depends on size of battery – influence on aging
Smaller capacity results in larger variation of SOC i.e. increased aging
String influence on invest (capex)
Prequalification requires 2 x 15 min full load, ENTSOE pushing towards 2 x 30 min
Technically 0.5 MWh / MW sufficient
Dwell time at respective SoC [h]
State of Charge (SoC) of the battery [%]
Stationary Battery Storage Systems

29. Battery Aging – Example: Lithium Ion Batteries
Cycle Life
Calendar Life
Impact Factors: ∆SoC and SoCavg
Shallow Cycles long lifetime
Deep Cycles short lifetime
Impact Factors: Temp. and SoCavg
Full LiB are aging faster
Cool LiB are aging slower
Stationary Battery Storage Systems

30. Lithium Ion Batteries – Functional Principle
Stationary Battery Storage Systems

31. High Temperature Batteries – Functional Principle
Stationary Battery Storage Systems