Abstract:
Using renewable energy sources to harvest energy is a priority in current era for energy
production sector. In various applications, the latent heat thermal energy storage
systems got a good response for the solar energy storage. An off grid Solar Thermal
Water Heating (STWH) system using a custom-build latent heat storage tank with
paraffin wax as Phase Change Material (PCM) is designed, developed and evaluated in
real-time. The paradigm shift of energy markets from conventional energy sources to
renewable energy sources of production has created an increased demand for the
creation of efficient energy storage systems to overcome the sustainability challenges.
To increase the overall efficiency of thermal energy storage systems, different
experiments has been performed to find out best parameters on which the heat transfer
is maximum. The experimentation is run on different flow rates. For PCM selection
different PCM characteristics has been studied. Fatty acids-based Phase change
materials (PCMs) are regarded as one of the most promising candidates to store and
release large amounts of latent heat, but they offer low thermal conductivity cause to
limits its applications. Paraffin waxes are also the most common PCM for electronics
thermal management because they have a high heat of fusion per unit weight, have a
large melting point selection, provide dependable cycling, are non-corrosive and are
chemically inert. The chemical structure characterization and thermal stability of PCMs
were performed using Thermal Gravimetric Analysis (TGA). The thermal
characteristics of charging and discharging processes and thermos-physical properties
were studied using the Differential Scanning Colorimetry (DSC). The results obtained
from DSC Method are compared with literature. A good agreement is found. The
experimental results yielded by utilizing both the techniques showed that the thermal
conductivity of the PCM is comparatively near to similar. From the findings, it can be
concluded that paraffin wax is very suitable candidate for domestic heating purposes.
The findings revealed that the performance provided by the Paraffin wax is good,
storing 2.1 MJ.kg of energy having 83.02% thermal efficiency and 0.69 ERR.
