This document discusses using phase changing materials (PCMs) for thermal energy storage. PCMs absorb heat when melting from solid to liquid at a certain temperature range, and release heat when solidifying from liquid to solid. The author proposes storing PCMs in building walls and HVAC systems to help maintain comfortable indoor temperatures and reduce energy usage. Various PCM options are described, along with encapsulation methods to control volume changes and prevent reactivity. Techniques for increasing PCM thermal conductivity, like adding metallic fillers or fins, are also summarized. The conclusion reiterates that further PCM research and system design optimization could improve energy storage efficiency.

1. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Phase Changing Material (PCM)
Thermal Energy Storage
Sudheer Nandi
M.Tech,MBA(Ph.D.)
Sustainable Energy ,S.korea.

2. What are PCM’s?
Absorbs heat
Liquid
Releases heat
Solid
Temperature is above melting point
Temperature is bellow melting point

3. 3

4. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Our Idea
• Storing PCM’s in the walls of the house/ building HVAC system.
• The goal is to sustain a specific temperature range for human comfort
• Decreasing the usage of energy by replacing air conditioners
• Used for heating the house in winter and cooling in summer

5. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
PCM Options

6. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
PCM Options

7. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ. 7
Fig. 1. (a) Latent heat of melting of paraffin compounds [4]. (b) Latent heat of melting of non-paraffin organic compoun
ds [4]. (c) Latent heat of melting/mass of inorganic compounds [4]. (d) Latent heat of melting/volume of inorganic comp
ounds [4]. (e) Latent heat of melting of eutectic compounds

8. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Encapsulation
• Prevents reactivity towards environment
• Compatible with stainless steel, polypropylene, and polyolefin
• Controls volume as phases change
• Prevents large drops in heat transfer rates

9. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Solid-liquid-gas PCM – Applications 1
• Macro-encapsulation
• Failed due to poor thermal conductivity
Failed due to poor thermal conductivity
• Tend to solidify at the edges
• Micro-encapsulation
•Easily incorporated into construction
materials
• Steel, polypropylene
• Usually embedded with high conductivity
materials with high conductive structure
Material’s Used in PCM

10. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Increasing Thermal Conductivity
• Metallic fillers
• Metal matrix structures
• Finned tubes
Aluminum filling with VSP 25 and VSP 50
PCM-Graphite Matrix
Finned Tubes

11. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
The VSP25 filling provided the highest
thermal conductivity of 1W/(mK), which
is about six times that of pure paraffin
Total solidification time of PCM is shorter
with fins and lessing rings, but the total quan
tity of stored heat is slightly smaller

12. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Conclusion
• Thermal energy storage is imperative to make energy more
reliable and competitive
• Further research in phase changing material can improve the
efficiency of energy storage
• Design of the system is also important in optimizing energy
storage

13. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
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14. Thermal Energy Conversion Control Lab. Chonbuk Nat’I Univ.
Thank you for listening
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