This paper compares the result generated by the Regenerator technique and the Ideriah’s method for instantaneous solar radiation. It considered the generation of the actual power input from the regenerator. The actual power input to the photovoltaic panel was calculated from a power model derived from the regenerator’s standard power that is nominally provided, regenerator material and reflectivity of the material. The amount of visible radiation absorbable by photovoltaic plates was further derived in the model and a value of 0.386Pi was obtained. The Ideriah’s model was used to calculate global solar radiation from extraterrestrial solar radiation. It utilized the concept of transmittance to arrive at the amount of insolation received locally (i.e. at the point of interest). It also calculated the amount of insolation at optical thicknesses (Air mass values) representing top of the hour from 5.0am to 7.0pm. Comparison & result showed that the regenerator model gave 84% to 97% correctness or an approximated average correctness of 94% when compared to the Ideriah’s model. Chi-square was used to test the relationship between the results. Chi-square results showed a high level of significance in the similarity of the results obtained. Python software was used to simulate the results and graph presentation.