Energy Storage – Resaerch-Based Demo ProjectsIn Germany

Andreas Hauer

TRILATERAL ENERGY STORAGE WORKSHOP, 19 NOVEMBERBRITISH AMBASSADOR’S RESIDENCE, PARIS

Energy Storage – Basic Definitions

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

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).

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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

Energy Storage – Technologies

Energy Storage Technologies

Electrical Energy Storage

Thermal Energy Storage

Chemical Energy Storage

Energy Storage – Applications

Constant Supply Fluctuating SupplyMatching Supply and Demand

„Storage of Power“ „Storage of Energy“

e.g. Power Reserve e.g. Peak Shaving / Dispatchable Load

Difference between Power & Energy

Pow

er

Pow

er

Seconds - Minutes Hours – Days

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

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

Some examples for Demo-Projectsin Germany

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

• 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

Island Solution „Smart Region Pellworm“

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“

© 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

© ZAE Bayern

Mobile Heat Storage for Waste HeatUtilization

© 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

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

Technology Comparison (?)

Storage technology

Storage Mechanis

m

Power Capacity Storage Period Density Efficiency Lifetim

e Cost

MW MWh time kWh/ton kWh/m3 % # cycles $/kW $/kWh

¢/kWh-deliver

edLithium 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 -

4500260 - 2560

210 - 920 9 - 55

Lead Acidbattery

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

bar0,4 - 0,75 8620 -

1710015 - 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 -

33000540 - 2790

40 - 160 0,1 - 18

Hydrogen Chemical varies varies indefinite 340002,7 - 160 at 1 - 700

bar0,22 - 0,50 1 384 -

1408 - 25 - 64

Methane Chemical varies varies indefinite 16000 10 at 1 bar 0,24 - 0,42 1 - - 16 - 44

Sensiblestorage - 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

Thermochemical 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!

Storage technology

Storage Mechanis

m

Power Capacity Storage Period Density Efficiency Lifetim

e Cost

MW MWh time kWh/ton kWh/m3 % # cycles $/kW $/kWh

¢/kWh-deliver

edLithium 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 -

4500260 - 2560

210 - 920 9 - 55

Lead Acidbattery

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

bar0,4 - 0,75 8620 -

1710015 - 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 -

33000540 - 2790

40 - 160 0,1 - 18

Hydrogen Chemical varies varies indefinite 340002,7 - 160 at 1 - 700

bar0,22 - 0,50 1 384 -

1408 - 25 - 64

Methane Chemical varies varies indefinite 16000 10 at 1 bar 0,24 - 0,42 1 - - 16 - 44

Sensiblestorage - 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

Thermochemical storage (TCS)

Thermal < 1 < 10 hour - week 120 -250 120 - 250 0,8 - 1 ~3500 - 10 -

130 1 - 5

Application: Long Term Storage

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

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

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

Conclusions

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

Thank you very much for your attention!