The evacuated tube solar collector is a proper choice for converting solar energy into heat since it is efficient, practical, and cost-effective. In the current study, the role of nanofluid in porous medium was numerically investigated to improve the performance of a solar collector model and the potential to store energy. The governing equations for the suggested model were solved analytically in the fully developed region using the Forchheimer model. The investigation of the impact on temperature fluctuation in the solar collector was done by considering several factors such as medium porosity, pore diameter, nanoparticles with respect to the solid volume ratio, system pressure, and conduit radius. The governing equations for the entrance region were expressed in a non-dimensional form and solved using the finite difference method (FDM), with the resulting non-dimensional differential equation solved using MATLAB software. Various parameters, such as Prantel number (Pr) and fluid vel