An energy source is required that has potential to reduce global warming, energy cost and create environmental sustainability. Solar energy is a viable candidate with 120 petajoules of energy on earth per second. To utilize this energy the present research explores the effect of the addition of conducting polyaniline (PANI) and cupric (II) oxide (CuO) nanoparticles within the matrix of paraffin wax. The Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analyzer (TGA), Differential Scanning Calorimetry (DSC), Ultraviolet-Visible-Near Infrared Spectrometer (UV-VIS) and thermal conductivity characterization of the prepared composite were performed. An enhancement of latent heat capacity of paraffin/PANI nanocomposite by 8.20% and paraffin/CuO composite by 7.81% was observed. Thermal conductivity of Paraffin/PANI was increased by similar to 46.8% for a 1% weight concentration of PANI in paraffin wax the same concentration as maximum latent heat capacity. In the case of paraffin/CuO composite, the maximum increment of thermal conductivity was found to be similar to 63.6%. To check the thermal reliability of the formulated nanocomposite, the base paraffin and nanocomposites were subjected to thermal cycling of 200 cycles. The DSC results showed that paraffin/PANI nanocomposite outperformed both base paraffin wax and paraffin/CuO composite. With comparable thermal conductivity to Paraffin/CuO composite, better latent heat capacity and improved thermal reliability Paraffin/PANI composite results are encouraging for the application in solar application area.