TERI-SAS, New Delhi
Development of medium temperature laboratory scale PCM based Thermal Energy Storage (TES)
Latent heat energy storage involves the storage of energy in Phase-Change Materials (PCMs) which can be stored and released with changes in the materials phase. Stored energy can be utilised to prevent mismatch between the energy supply and the power demand as well as for waste heat recovery. A shell and tube type lab-scale latent heat thermal energy storage (LHTES) prototype unit had been developed for the experimental analysis with a (latent) storage capacity of about 320-330 kJ.
Work done
Literature Study: Understanding the concept
Basic calculations for storage capacity of prototype
Prototype set-up establishment & commissioning
Phase Change Material development, Selection & Testing using DSC
Differential Scanning Calorimetry (DSC)
DSC experiments have used to decide the appropriate and handleable phase change material (PCM) at shell side. The mixture of potassium nitrate, sodium nitrate and sodium nitrite in the weight proportion of 53:7:40 with phase change temperatures between 130°C - 142°C has been used for the analysis. Hi-tech Therm 60 is used as heat transfer fluid (HTF) flows in nine internal tubes.
DSC results and comparison
Technical issues faced
Leakage
Temperature Measurement (Shell side measurement, Thermocouple calibration)
Homogeneousness of salts mixture