Multi-purpose Pit Thermal Energy Storage in Combination ...

7th International Conference on Smart Energy Systems21-22 September 2021

#SESAAU2021

Multi-purpose Pit Thermal Energy Storage in Combination with Heat Pumps

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Funded by the European Union’sHorizon 2020 Research and Innovation Programme under Grant Agreement no. 846463

Morten Vang Bobach – MSc Mechanical Engineering

Product Manager

mvb@aalborgcsp.com

7th International Conference on Smart Energy Systems21-22 September 2021

2

PTES, Pit Thermal Energy Storage Low cost storing energy in a green future

• A flexible energy system that will enable the conversion from conventional fossil fuel energy to fluctuating renewable energy sources requires large scale energy storage.

• The PTES technology is a low-cost energy storage for thermal energy up 90°C. Energy is simply stored in pure water.

• PTES enables storing of excess energy for later use in district heating networks resulting in increased flexibility and efficiency of the heat production. This includes:

• excess heat from solar heating plants, power plants or industrial processes

• excess electricity produced by wind or PV stored as heat

• Collecting waste heat/power and using it for district heating later helps lower energy loss and reduces our carbon footprint.

7th International Conference on Smart Energy Systems21-22 September 2021

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PTES, Pit Thermal Energy Storage The next generation of storing energy in a green future

7th International Conference on Smart Energy Systems21-22 September 2021

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Combining PTES and heat pump

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

Heat pump / ORC

Compressor mode

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

7th International Conference on Smart Energy Systems21-22 September 2021

5

Reverse the proces – PTES as electricity storage

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

Heat pump / ORC

Expander mode

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

7th International Conference on Smart Energy Systems21-22 September 2021

6

Efficiency - Charging

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

(Energy Units from theoretical Lorentz efficiency)

1(electricity)

8(heat)

Heat pump / ORC

Compressor mode

9(heat)

7th International Conference on Smart Energy Systems21-22 September 2021

7

Efficiency - Discharging

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

Heat pump / ORC

Expander mode

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

1(electricity)

8(heat)

9(heat)

(Energy Units from theoretical Lorentz efficiency)

7th International Conference on Smart Energy Systems21-22 September 2021

8

Round trip efficiency – power to power

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

(Energy Units from theoretical Lorentz efficiency)

1(electricity)

8(heat)

Heat pump / ORC

Compressor mode

9(heat)

Wind turbinePhotovoltaic solar collectors

PTES

Solar thermal

collectors

Heat pump / ORC

Expander mode

DH Consumers

PTES

Industry

Low temperature heat source

- Exces heat from industry

- Cooling processes

- Flue gas condensation

- Solar thermal collectors

- …

50°C 85°C

85°C

50°C

50°C

10°C

10°C

10°C

50°C

50°C 85°C

50°C85°C

85/50°C

50/10°C

1(electricity)

8(heat)

9(heat)

(Energy Units from theoretical Lorentz efficiency)

Ideal:

η = 9/1 = 9

Realistic?:

η = 9*0.7 = 6.3

Charging

Ideal:

η = 1/9 = 0.11

Realistic?:

η = 0.11*0.7 = 0.08

Discharging

Ideal:

η = 9*1/9 = 1

Realistic?:

η = 6.3*0.08 = 0.50

Round trip power to power

THANK YOU FOR YOUR ATTENTION

Multi-purpose Pit Thermal Energy Storage in Combination withHeat Pumps

Morten Vang Bobach – MSc Mechanical Engineering

Product Manager

mvb@aalborgcsp.com