Modelling results on New Generation Solar Cooling systems · Chiara Dipasquale –Modelling results...

Modelling results on New Generation Solar Cooling systems

Chiara Dipasquale

Chiara Dipasquale – Modelling results on New Generation Solar Cooling systems

4 examples of new generation solar cooling systems:

• Building description and solar cooling plant layout;

• Working modes and characteristics of system components;

• Operational modes and system size variants, and results.

INTRODUCTION

2


Building description

CASE 1

Reference Single Family House - SFH Reference Small Multi Family House - sMFH

Number of floors 2

Living area per floor 50 m²

Yearly heating demand 45 kWh/(m²y)

Number of floors 5

Living area per dwelling 50 m²

Number dwelling per floor 2


3


Solar cooling plant layout

CASE 1

GENERATION DEVICE

HJ_HYDRAULIC JUNCTION

DHW

BUF_BUFFER

TES_THERMAL ENERGY STORAGE

STC_SOLAR THERMAL COLLECTORS

T5.2

T1.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC

DISTRIBUTION DEVICES

1. Solar thermal collectors2. PV panels3. Air-to-water heat pump4. Storage tank5. Buffer6. DHW distribution circuit7. H&C Distribution circuit

1

2

3

4

5

7

6

• Use of solar thermal energy for DHW production and space heating

• Use of PV energy for the HVAC system electricity consumption

4


A/W HEAT PUMP


DHW

VM2_3

VM1_6

C5

C6

C1

C2

TES_SNS5

C1

BUF_BUFFER



C6

C5

0

1

PM1_5C2

C1

0

1

1

0

VM1_7

C6

C5

0

1

PM1_6C2

C1

VM1_5PM2_4

C6

C5

C2

C1

HX_2

PM1_1

PM2_2

VM1_4VM_2

1

0

TES_SNS3

TES_SNS2

200 l

C3

C5

T5.2

0

1

PM2_3

C2

C1

T1.3

C2

C4 C6

C5

C6

C4C3out

BUF_SNS1

BUF_SNS5

HX_1

T5.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC

VD_1

VM2_2

VM

CASE 1

5

Working conditions

TES charging by solar energy


A/W HEAT PUMP


DHW

VM2_3

VM1_6

C5

C6

C1

C2

TES_SNS5

C1

BUF_BUFFER



C6

C5

0

1

PM1_5C2

C1

0

1

1

0

VM1_7

C6

C5

0

1

PM1_6C2

C1

VM1_5PM2_4

C6

C5

C2

C1

HX_2

PM1_1

PM2_2

VM1_4VM_2

1

0

TES_SNS3

TES_SNS2

200 l

C3

C5

T5.2

0

1

PM2_3

C2

C1

T1.3

C2

C4 C6

C5

C6

C4C3out

BUF_SNS1

BUF_SNS5

HX_1

T5.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC

VD_1

VM2_2

VM

CASE 1

6

Working conditions

TES charging by heat pump


A/W HEAT PUMP


DHW

VM2_3

VM1_6

C5

C6

C1

C2

TES_SNS5

VD_1

VM2_2

C1

BUF_BUFFER



C6

C5

0

1

PM1_5C2

C1

0

1

1

0

VM1_7

C6

C5

0

1

PM1_6C2

C1

EH6

VM1_5PM2_4

C6

C5

C2

C1

HX_2

PM1_1

PM2_2

VM1_4VM_2

1

0

TES_SNS3

TES_SNS2

200 l

C3

C5

T5.2

0

1

PM2_3

C2

C1

T1.3

C2

C4 C6

C5

C6

C4C3out

BUF_SNS1

BUF_SNS5

HX_1

T5.3

T5.4

T5.5

T5.6

VM

T6.1

PV_PHOTOVOLTAIC

CASE 1

7

Working conditions

Buffer charging by heat pump


A/W HEAT PUMP


DHW

VM2_3

VM1_6

C5

C6

C1

C2

TES_SNS5

C1

BUF_BUFFER



C6

C5

0

1

PM1_5C2

C1

0

1

1

0

VM1_7

C6

C5

0

1

PM1_6C2

C1

VM1_5PM2_4

C6

C5

C2

C1

HX_2

PM1_1

PM2_2

VM1_4

PV_PHOTOVOLTAIC

VM_2

1

0

TES_SNS3

TES_SNS2

200 l

C3

C5

T5.2

0

1

PM2_3

C2

C1

T1.3

C2

C4 C6

C5

C6

C4C3out

BUF_SNS1

BUF_SNS5

HX_1

T5.3

T5.4

T5.5

T5.6

T6.1

VD_1

VM2_2

VM

CASE 1

8

Working conditions

Buffer charging by solar energy


A/W HEAT PUMP


DHW

VM2_3

VM1_6

C5

C6

C1

C2

TES_SNS5

C1

BUF_BUFFER



C6

C5

0

1

PM1_5C2

C1

0

1

1

0

VM1_7

C6

C5

0

1

PM1_6C2

C1

VM1_5PM2_4

C6

C5

C2

C1

HX_2

PM1_1

PM2_2

VM1_4VM_2

1

0

TES_SNS3

TES_SNS2

200 l

C3C5

T5.2

0

1

PM2_3

C2

C1

T1.3

C2

C4 C6

C5

C6

C4C3out

BUF_SNS1

HX_1

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC

VD_1

VM2_2

Working conditions

CASE 1

9

DHW distribution


ST and PV performance with varying field size and tilt angle

RESULTS – CASE 1

GENERATION DEVICE


DHW

BUF_BUFFER



T5.2

T1.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC


Solar Fraction and stagnation hours referred

to the total heating production (space heating

+ DHW)10

0

100

200

300

400

500

600

700

0%5%

10%15%20%25%30%35%40%

30° 90° 30° 90°

STC_1 STC_1 STC_3 STC_3 Stag

nat

ion

nu

mb

er h

ou

rs [h

]

Sola

r Fr

acti

on

[%]

Solar Thermal Collectors - s-MFH

SF_ROM SF_STO Hour_ROM Hour_STOROM – Rome

STO - Stockholm

Solar ThermalUnit s-MFH

STC_1 m² 18.4STC_2 m² 27.6STC_3 m² 36.8


RESULTS – CASE 1

GENERATION DEVICE


DHW

BUF_BUFFER



T5.2

T1.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC


Solar ThermalUnit s-MFH

STC_1 m² 18.4STC_2 m² 27.6STC_3 m² 36.8

Solar Fraction and stagnation hours referred

to the total heating production (space heating

+ DHW)11

PV production and self-consumption for two

different fields size and panel slope

0

2000

4000

6000

8000

10000

30° 90° 30° 90° 30° 90° 30° 90°

ROM_3 kW ROM_5 kW STO_3 kW STO_5 kW

Ener

gy [k

Wh

]

PV production - s-MFH

PV self HVAC PV self other PV to the grid

0

100

200

300

400

500

600

700

0%5%

10%15%20%25%30%35%40%

30° 90° 30° 90°

STC_1 STC_1 STC_3 STC_3 Stag

nat

ion

nu

mb

er h

ou

rs [h

]

Sola

r Fr

acti

on

[%]

Solar Thermal Collectors - s-MFH

SF_ROM SF_STO Hour_ROM Hour_STO

PhotovoltaicUnit s-MFH

PV_1 kWp 3PV_2 kWp 4PV_3 kWp 5

ROM – Rome

STO - Stockholm

ST and PV performance with varying field size and tilt angle


RESULTS – CASE 1

GENERATION DEVICE


DHW

BUF_BUFFER



T5.2

T1.3

T5.4

T5.5

T5.6

T6.1

PV_PHOTOVOLTAIC


Comparison of similar field areas of STC (27 m²) or

PV (24 m²) in terms of electric energy savings for

DHW, heating and cooling uses

12

0

5

10

15

20

25

30

35

40

NO_ST_PV STC_2 PV_1 NO_ST_PV STC_2 PV_1

ROME STOCKHOLM

Fin

al E

ner

gy [

kWh

/(m

²y)]

Electricity consumption - s-MFH

14%20

%

23%

14%

ST and PV performance for different sizes and slopes

• Slightly higher energy savings in Southern climates due to higher cooling loads

• Same energy savings for a solar thermal (STC) or photovoltaic (PV) field in Northern climates

ROM – Rome STO – Stockholm



CASE 2

Wooden Residential Building (WRB)

Number of floors 2


13



CASE 2

1. Compound Parabolic Collectors (CPC)2. Storage tank – 1000 l3. Electric Heater4. Adsorption chiller – 10 kW5. Dry cooler6. Fan coil

• Adsorption chiller for space cooling;• Solar collectors (CPC) for heating

and DHW demands• Heat rejection through dry-cooler.

14


CASE 2

Running the solar system

Working conditions

15


<

CASE 2Working conditions

Space cooling mode

16



Running the back-up heater

17



Domestic Hot Water and space heating

18


Absorption chiller in different climates

RESULTS – CASE 2

19

# solar collectors

SPF heating[-]

SPF cooling[-]

SF total [%]

PER total[-]

Freiburg 6 6.7 5.2 51% 1.2

Stuttgart 6 9.5 7.9 56% 1.3

Marseille 6 11.6 9.6 92% 1.9

Messina 8 14.8 12.3 67% 2

Luca 8 14.3 13.0 66% 2

Athens 8 10.4 10.9 69% 2.4

Barcelona 8 12.9 11.7 73% 2.4

Almeria 8 10.7 11.8 66% 1.9

Larnaca 10 11.9 12.7 63% 2.1

• The highest SF is in Marseille where heating and cooling demands are similar;



RESULTS – CASE 2

20

# solar collectors

SPF heating[-]

SPF cooling[-]

SF total [%]

PER total[-]

Freiburg 6 6.7 5.2 51% 1.2

Stuttgart 6 9.5 7.9 56% 1.3

Marseille 6 11.6 9.6 92% 1.9

Messina 8 14.8 12.3 67% 2

Luca 8 14.3 13.0 66% 2

Athens 8 10.4 10.9 69% 2.4

Barcelona 8 12.9 11.7 73% 2.4

Almeria 8 10.7 11.8 66% 1.9

Larnaca 10 11.9 12.7 63% 2.1


• Northern climates have low SF due to small collector size and high heating demand;



RESULTS – CASE 2

21

# solar collectors

SPF heating[-]

SPF cooling[-]

SF total [%]

PER total[-]

Freiburg 6 6.7 5.2 51% 1.2

Stuttgart 6 9.5 7.9 56% 1.3

Marseille 6 11.6 9.6 92% 1.9

Messina 8 14.8 12.3 67% 2

Luca 8 14.3 13.0 66% 2

Athens 8 10.4 10.9 69% 2.4

Barcelona 8 12.9 11.7 73% 2.4

Almeria 8 10.7 11.8 66% 1.9

Larnaca 10 11.9 12.7 63% 2.1


• Northern climates have low SF due to small collector size and high heating demand;

• Although Northern climates are not the best application for adsorption chillers, all the cases have PER (Primary Energy Ratio) > 1 and Solar Fraction > 60%



CASE 3

TheBat Building (Task 44)

Number of floors 2



Location: Innsbruck (Austria)

22



CASE 3

1. PV PV panels – 20 m² - 40 m²2. HP Heat pump – 10 kW3. DHW Domestic Hot Water4. SH Space heating5. TES Thermal Energy Storage6. TABS Thermal Activated Building

Structure

Use of PV for covering the heat pump consumption:

1. SELF consumption;2. Overheating the TES;3. Overheating the TABS;4. Overheating TES and TABS.

23


Working conditions

CASE 3

TES charging for DHW uses

24


CASE 3

TES charging for space heating use

25

Working conditions


CASE 3

Direct space heating from the heat pump

26

Working conditions


SPF and HP performance at different working conditions

RESULTS – CASE 3

27

• The strategy of overheating the TES reduces the HP performance (SPFel,HP) because of the higher working temperatures;


RESULTS – CASE 3

28


• Overheating the BUI and the TES+BUI increases the thermal losses;



RESULTS – CASE 3

29


• Overheating the BUI and the TES+BUI increases the thermal losses;

• Bigger PV field area and storage capacity reduce the used energy from the grid, but increase energy losses;

• Bigger storages do not significantly improve the system performance.




CASE 4

Multi-family house HVACviaFaçade

Location: Graz (Austria)

Number of floors 3

Living area per dwelling 50.3 m² (average)

Dwellings per floor 4

Yearly heating demand 15 kWh/(m²y) – BUI 15

Yearly heating demand 30 kWh/(m²y) – BUI 30

30


Layout description

CASE 4

Central outdoor air heat pump Decentralized outdoor air heat pump Direct electric heating

31


CASE 4 - 1

Central outdoor air heat pump

1. PV panels 189 m² - 15.75 m²/dwelling2. Heat pump 10 kW (BUI 15) – 20 kW (BUI 30)3. Buffer Tank – 1500 l (BUI 15) – 2000 l (BUI 30)4. DHW tank – 150 l/dwelling5. Mechanical Ventilation with Heat Recovery

• Maximize PV production for the centralized heat pump electric consumption;

• Use of decentralized storages for DHW uses;• Use of two set temperatures for the tanks.

1

23

4

5

32

Layout description and working conditions


CASE 4 - 2

Decentralized outdoor air heat pump

1. PV panels 176 m² - 14.5 m²/dwelling2. Heat pump 2 kW/dwelling3. Direct space heating from the heat pump4. DHW tank – 150 l/dwelling5. Mechanical Ventilation with Heat Recovery

• Maximize PV production for the decentralized heat pumps consumption;

• Use of decentralized storages for DHW uses;• Use of two set temperatures for the tanks.

1

2

3

4

5

33



CASE 4 - 3

Direct electric heating

1 2

3 4

1. PV panels 1 176 m² - 14.5 m²/dwelling2. PV panels 2 419 m² - 34.9 m²/dwelling3. Electric heater 2.5 kW and 150 l4. Mechanical Ventilation with Heat Recovery

• Maximize PV production for self-use;• Use of two set temperatures for the tank;• Use of the roof surface for additional PV

panels.

34



SPF and SCOP

RESULTS – CASE 4

#1: Central heat pump #2: Heat Pump in each apartment #3: Direct electrical heating

35

• SCOP is slightly lower in cases with a PV field due to the higher working temperatures

• The highest SPFs are encountered in the decentralized configuration;

• However, a low energy demanding building with a big PV field has a high SPF.


SPF and SCOP

RESULTS – CASE 4

#1: Central heat pump #2: Heat Pump in each apartment #3: Direct electrical heating

36

• SCOP is slightly lower in cases with a PV field due to the higher working temperatures

• The highest SPFs are encountered in the decentralized configuration;

• However, a low energy demanding building with a big PV field has a high SPF.

• Self-consumption accounts for one third to a half of the total production.

• The excess of electricity fed into the grid is high in all cases, with exception of the direct heating with small PV field


CONCLUSIONS• Solar driven systems can assume different configurations, from the PV coupled to a heat

pump for heating production to the integration of solar thermal collectors for decreasing thermal loads to the use of sorption chillers for the cooling loads;

• When designing a solar energy system, the solar field size is key, in fact bigger solar thermal fields can cause stagnation problems and in PV systems the self-consumption can be only a small fraction of the produced energy (20% to 30%);

• Solar technologies have good results in terms of solar fraction and SPF also in northern climates thanks to the longer winter season and the inclination of solar radiation in this period.

• The use of thermal storages can help to maximize the use of solar energy also in combination with PV systems.

37

Chiara Dipasquale – [email protected]

THANK YOU

www.eurac.eduhttp://task53.iea-shc.org/

http://www.eurac.edu/

http://task53.iea-shc.org/

Modelling results on New Generation Solar Cooling systems · Chiara Dipasquale –Modelling results...

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Transcript of Modelling results on New Generation Solar Cooling systems · Chiara Dipasquale –Modelling results...