team dtu - elforsk.dk · master thesis presentation – september 11th luca gennari – s121590...

TEA

M D

TU

Conditioning of a Plus-energy House Using Solar Systems for Both Production of Heating and Nighttime Radiative Cooling

Master thesis presentation – September 11th

Luca Gennari – s121590

s121584 – Thibault Péan

Supervisors: Bjarne W. Olesen – Ongun B. Kazanci – Peter Weitzmann – Jørn Toftum

Introduction

I. SDE2014 – EMBRACE

II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

Conditioning of a Plus-energy House Using Solar Systems for Both Production of Heating and Nighttime Radiative Cooling 3

Agenda

Conditioning of a Plus-energy House using Solar Systems for both Production of Heating and Nighttime Radiative Cooling

Solar Decathlon Europe 2014

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

4

1. Architecture 120 pts

2. Engineering and Construction 80 pts

3. Electrical Energy Balance 120 pts

4. Energy Efficiency 80 pts

5. Comfort Conditions 120 pts

6. House Functioning 120 pts

7. Communication and Social Awareness

80 pts

8. Urban Design, Transportation and Affordability (UDTA)

120 pts

9. Innovation 80 pts

10. Sustainability 80 pts



Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

5

1. Architecture 120 pts

2. Engineering and Construction 80 pts

3. Electrical Energy Balance 120 pts

4. Energy Efficiency 80 pts

5. Comfort Conditions 120 pts

6. House Functioning 120 pts


80 pts


120 pts

9. Innovation 80 pts

10. Sustainability 80 pts



Indoor temperature range: Tav-1 < Tindoor < Tav+1 + Humidity, CO2, VOCs and formaldehyde criteria

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

6

1. Architecture

2. Engineering and Construction

3. Electrical Energy Balance

4. Energy Efficiency

5. Comfort Conditions

6. House Functioning



9. Innovation 10. Sustainability


SDE2014 – EMBRACE

Solar Decathlon Europe 2014 Cité du Soleil - Versailles

EMBRACE Team DTU

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

7


Envelope

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

8

•Integration on rooftops to densify cities • Small dwelling •Thermal envelope: 4 modules • Sheltered garden acting as a buffer zone

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Envelope

9


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Envelope

10


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Envelope

11

59m2


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Envelope

12

• Integration on rooftops to densify cities • Small dwelling •Thermal envelope: 4 modules • Sheltered garden acting as a buffer zone


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

13

Construction U-value

(W/m2K)

External wall 0,08

Roof 0,085

External floor 0,1

Internal walls 0,38

Internal floor 0,25

Glazing 1st type U-window 0,83

Glazing 2nd type U-window 0,79

Envelope


HVAC overview – heating and cooling sources

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

14

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Realized system: DHW/Ventilation

15


Realized system: sources

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

16

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Realized system: storage/delivery

17

4-way valve

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Realized system: emission/regulation

18


Sizing process

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

19

IDA-ICE Load Calculations

Radiant floor sizing EN 1264/HEAT2

Dimensioning room

HEATING

Dimensioning room

COOLING

36 W/m2 41 W/m2

1600 W 1500 W

Demand distribution over the season

SCOP 3,8 EER 4,4

Supply water temperature

Daikin simulation

tool

Copenhagen Paris


Sizing process

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

20



Dimensioning room

HEATING

Dimensioning room

COOLING

36 W/m2 41 W/m2

1600 W 1500 W


SCOP 3,8 EER 4,4


Daikin simulation

tool

Heat pump

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Heat pump

21

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Heat pump

22

Heating demand =1,6 kW Cooling demand = 1,5 kW

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

1ST

preferred

2ND

realized


Heat pump

23


Sizing process

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

24



Dimensioning room

HEATING

Dimensioning room

COOLING

36 W/m2 41 W/m2

1600 W 1500 W


SCOP 3,8 EER 4,4


Daikin simulation

tool

Radiant floor


Radiant floor – EN 1264 – Type B

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

25

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14

He

at

flu

x q

(W

/m2)

ΔϑH = |Troom-Taverage water| (°C)

Heating, tilesHeating, wood 7 mmHeating, wood 15 mm

0 2 4 6 8 10 12 14


Cooling, tilesCooling, wood 7 mmCooling, wood 15 mm

Single power equation – Characteristic curves

0 2 4 6 8 10 12 14


Cooling, tilesCooling, wood 7 mmCooling, wood 15 mm

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14

He

at

flu

x q

(W

/m2)


Heating, tilesHeating, wood 7 mmHeating, wood 15 mm


Radiant floor – EN 1264

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

26

Choice of the floor covering

Tiles: λ = 1,5 W/mK

Chipboard: λ = 0,15 W/mK

0 2 4 6 8 10 12 14


0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14

He

at

flu

x q

(W

/m2)



Radiant floor – EN 1264

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

27

Determination of the water supply temperature

Supply 28,5°C Room 20°C

Supply 15,6°C Room 26°C

Surface temperature in the range 20-24°C, no condensation problem


Comparison standard – HEAT2

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

28

q (W/m2) Δϑ heating = 7,9°C Δϑ cooling = 8,6°C

EN 1264 50,1 39,5

HEAT2 46 39,9

8% 1%

Case of the tiles as floor covering


Results – Yearly Electricity consumption

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

29

IDA-ICE Simulation

Paris 32 kWh/m²/year

(net area)

Copenhagen 38 kWh/m²/year

(net area)

SCOP; EER

13 kWh/m² for

appliances


Results – Energy consumption: cooling mode

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

30

Simulation

Competition

23%

10%

10%

7%

50%

19%

23%

7% 7%

44%

Copenhagen (%)

22%

11%

7%

14%

44%

Paris (%)


Results – Energy production

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

31

0

5

10

15

20

25

30

35

40

30-6 1-7 2-7 3-7 4-7 5-7 6-7 7-7 8-7 9-7 10-7 11-7

En

erg

y (

kW

h)

Production Consumption

=> Plus-energy house


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

32

Operative Temperature

Range

Competition range (±1°C)

based on EN15251

Lower limit not

considered

Percentage of time outside the range

27 % 2 %

Results – Comfort Conditions

Relative Humidity

CO2 level

Range 40% < RH < 55% < 800 ppm

Percentage of time outside the range

6% 11 %


Competition rankings

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

33

Sub contest Points earned by Team

DTU

Ranking of Team

DTU

Electrical Energy Balance 79,22 / 120 #7

Energy Efficiency 71,84 / 80 #9

Comfort Conditions 99,23 / 120 #8

TOTAL 780,01 / 1000 #8


Nighttime radiative cooling

Unglazed collector vs. photovoltaic thermal (PVT)

Outputs: cooling power (W/m2), energy (kWh), COP (-)

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

34

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Theory – Heat losses

35

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Theory – Longwave thermal radiation

𝑇𝑠𝑘𝑦 , 𝜀 = 1

36

Stefan-Boltzmann law

𝑇𝑟 , 𝜀 𝑟

𝑄𝑟𝑎𝑑

𝑞 = 𝜎 ∙ 𝜀 ∙ 𝑇4

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion




𝑇𝑎𝑖𝑟 , 𝜀𝑠𝑘𝑦

37


𝑇𝑟 , 𝜀 𝑟 𝑇𝑟 , 𝜀 𝑟

𝑄𝑟𝑎𝑑

𝑄𝑟𝑎𝑑

𝑞 = 𝜎 ∙ 𝜀 ∙ 𝑇4

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion



45°



𝑇𝑟𝑎𝑑 , 𝜀 = 1

38




𝑄𝑟𝑎𝑑

𝑄𝑟𝑎𝑑

𝑄𝑟𝑎𝑑

𝑞 = 𝜎 ∙ 𝜀 ∙ 𝑇4

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion



45°



𝑇𝑟𝑎𝑑 , 𝜀 = 1

39




𝑄𝑟𝑎𝑑

𝑄𝑟𝑎𝑑

𝑄𝑟𝑎𝑑

𝑞 = 𝜎 ∙ 𝜀 ∙ 𝑇4

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion



40

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion



41

Relative Humidity

Air temperature

Atmospheric pressure

Cloud amount

Cloud height

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Cooling powers

Theory Heat flux sensors

VFS - Water

Plane radiant & surface temperatures

Weather data

Supply flow and temperature

Returns flows and temperatures

42

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

19:00 21:00 23:00 01:00 03:00 05:00 07:00

Unglazed collector


Experiment results

0

20

40

60

80

100

120

140

19:00 21:00 23:00 01:00 03:00 05:00 07:00

Co

oli

ng

po

we

r

(W/

m2)

43

PVT

August 20th – Clear sky

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Experiment results

0

20

40

60

80

12/08 13/08 14/08 16/08 17/08 18/08 19/08 20/08 21/08 22/08 23/08 24/08 25/08

Co

oli

ng

po

we

r (W

/m

2)

PVT Unglazed

44

19:00 21:00 23:00 01:00 03:00 05:00 07:00

Unglazed collector

0

20

40

60

80

100

120

140

19:00 21:00 23:00 01:00 03:00 05:00 07:00

Co

oli

ng

po

we

r

(W/

m2)

PVT


Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Experiment results: Radiation vs. Convection

45

0

10

20

30

40

50

60

70

80

90

100

19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00

Co

oli

ng

po

we

r (W

/m2)

Time


Convection

Radiation

Total

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Experiment results: Radiation vs. Convection

46

0

10

20

30

40

50

60

70

80

90

100

19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00

Co

oli

ng

po

we

r (W

/m2)

Time


Convection – Simplified

Radiation

Total – Simplified

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Experiment results

PVT Unglazed collector

Cooling power (average per night) 28 to 74 W/m2 20 to 72 W/m2

Cooling power (literature) 60 to 65 W/m2 ~50 W/m2

Cooling COP 19 to 58

Heating power (average Aug 28th) 247 W/m2 241 W/m2

Heating energy (Aug 28th) 9,25 kWh 5,74 kWh

47


TRNSYS: flow rate selection

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

48

14

16

18

20

22

24

26

28

30

18:00 20:00 22:00 0:00 2:00 4:00 6:00 8:01

Te

mp

era

ture

(°C

)

Time (h)

Flow 0,1 l/min.m2

Flow 0,3 l/min.m2

Flow 0,6 l/min.m2

Flow 1,7 l/min.m2

Supply temperature

Inlet temperature fixed at 22°C

Flow rate (l/min.m2) 0,1 0,3 0,6 1,7

Cooling power per average night (W/m2) 30 53 63 72


TRNSYS vs. Experiment

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

49

67,3 69,7 68,1

83,0

0

10

20

30

40

50

60

70

80

90

Heat Flux sensors Theory VFS TRNSYS

Av

era

ge

co

oli

ng

po

we

r (W

/m

2)

Comparison for August 13th

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion


Discussion

50

EMBRACE • Reliability of simulations supported by Standards-Experiment • Time issues/ difficult central control changes • Competition rules • High consumption per m2

consumption per person

Nighttime radiative cooling • Inaccuracies in the measurements (VFS, rain) • Limited potential in Denmark


Conclusion

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

51

EMBRACE • EMBRACE ranking: #8 • Good performance in Comfort Conditions, Energy Efficiency

and Electrical Energy Balance

Nighttime radiative cooling • High savings potential in cooling (high COP) • Economical potential (PVT, unglazed)

o Possibility of utilizing existing solar installations o Residential use in Southern climates o Public buildings use in Denmark


Future research

Introduction


II. HVAC

III. Radiant floor

IV. Performance

V. Nighttime

radiative cooling

Discussion

Conclusion

52

• Sheltered garden • Potential of nighttime radiative cooling in different climates • Coupling with PCM • Coupling with heat pump condenser

THANKS FOR THE GREAT EXPERIENCE!

team dtu - elforsk.dk · master thesis presentation – september 11th luca gennari – s121590...

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