1. ACTIVE BUILDING ELEMENTS WITH PCM
GRADUATION PROJECT: THERMAL SIMULATION OF AN ENERGY
NEUTRAL BUILDING CONCEPT.
IR. BART KOLKMAN

2. CONTENT
Introduction
Concept design
Model development
Development of simulation software
Optimizations and results
Conclusions
Active building elements with pcm 8-June-2012

3. INTRODUCTION
 Reduction of energy consumption of buildings
 Smart energy storage and release
 Using PCM materials
Material without phase
change
Temperature
Heat of fusion
PCM
Stored heat
Active building elements with pcm 8-June-2012

4. INTRODUCTION
 Reduction of energy consumption of buildings
 Smart energy storage and release
 Using PCM materials
 Simulation of buildings using PCM in walls
Active building elements with pcm 8-June-2012

5. CONCEPT DESIGN OF BUILDING
Ventilation box Walls (Thermal or PV)
Module
Window with
shutter Battery
Internal heat
+-
Heat flows
Basin
Active building elements with pcm 8-June-2012

6. WALL DESIGN
Thermal collector
Combined thermal + PV collector
Internal External
air air
Photo-
voltaic
material
PCM/water Aluminum plate
layer Isolation with water
channels
Active building elements with pcm 8-June-2012

7. ENVIRONMENTAL VARIABLES
Dutch weather conditions
Solar irradiance
External air
temperature, wi
nd speed and
direction
Ground
Internal solar irradiance
temperature
Active building elements with pcm 8-June-2012

8. MODEL DEVELOPMENT
WALL 1D FINITE ELEMENT MODEL
Thermal masses Resistances
Dynam icWallModel
Active building elements with pcm 8-June-2012

9. MODEL DEVELOPMENT
WALL 1D FINITE ELEMENT MODEL
Active building elements with pcm 8-June-2012

10. MODEL DEVELOPMENT
WALL 1D FINITE ELEMENT MODEL
Active building elements with pcm 8-June-2012

11. SIMULATION SOFTWARE
Composition of:
1. Thermal model
 Thermal state of walls and internal volume, based on previous state
2. Shape model
 Defines the shape en position of walls, window, etc.
 Calculation of external influences on the model (wind, solar irradiance)
 Calculation of shined areas through window
3. Controller
 Heating and cooling of thermal masses, functioning of the ventilation
box and window shutter
Active building elements with pcm 8-June-2012

12. RESULTS
Active building elements with pcm 8-June-2012

13. RESULTS
Optimization of design for:
 Heat collection
 Passive heating of the interior
 Heat storage
 Electricity storage
Fine-tuning of model by various simulations
Active building elements with pcm 8-June-2012

14. OPTIMIZATIONS OF HEAT COLLECTION
Optimization parameters:
 Choice of:
 black anodized aluminum or
 selective absorber surface material
 Optional glass cover
 Efficient collectors are essential to have enough heat generation in the
spring and autumn, minimizing the need for thermal storage.
 Uncovered collectors have too low efficiencies at low external
temperatures
 Selective absorber material is performing better, especially at lower
irradiation levels
Active building elements with pcm 8-June-2012

15. OPTIMIZATION OF PASSIVE HEATING
Optimization parameters:
 Window area. [1 m2, 2 m2, 4 m2]
 PCM thickness of inner wall. [10 mm, 20 mm, 30 mm]
 Increased window area and PCM thickness gives lower heating
requirements and reduced maximal temperatures
Active building elements with pcm 8-June-2012

16. OPTIMIZATION OF HEAT STORAGE
Optimization parameters:
 Basin height. [0.1 m, 0.3 m, 0.5 m]
 Basin isolation thickness. [200 mm, 100 mm]
 Basin internal material. [Water, PCM]
 Small water basin can be used but results in high storage
temperatures and thereby high losses.
 Use of 3 cm PCM is sufficient, and also reduces the conduction losses
due to the lower storage temperatures.
Active building elements with pcm 8-June-2012

17. OPTIMIZATION OF ELECTRICITY STORAGE
Variables:
 Battery capacity
 Battery efficiency
 Inclination of the roof [0°, 17°,35°]
 The production per month exceeds the consumption.
 An efficient storage system is essential.
 Inclination of the roof increases the electric yield, but reduces the
thermal performance of the building and is therefore not ideal.
Active building elements with pcm 8-June-2012

18. FINE-TUNING OF MODEL
LONGER SIMULATION PERIOD AND FINE-TUNING
 Simulation over a longer period (multiple years)
 More thermal and electric capacity is sometimes required.
 Replacement of PCM/water layer by pure PCM for some sides.
Active building elements with pcm 8-June-2012

19. CONCLUSIONS
 Both practical and theoretical approach
 Satisfying results for inside temperature
 PCM in basin and walls gives good opportunities for energy reduction
 Integrated solution with:
 Control system
 Different energy resources
 Smart storage and release of energy
Active building elements with pcm 8-June-2012

20. CURRENT WORK AREA
 Development of simulations for various applications
 Obtain integrated solutions for multi-variable problems
THANK YOU FOR YOUR ATTENTION
Active building elements with pcm 8-June-2012