In concentrated solar power (CSP) hybridized systems, the selection of solar-hybrid power plants (SHPP) is very important, especially when the selected criteria and performance indicators are fuzzy and uncertain. The multi-criteria intuitionistic fuzzy decision-making method for selecting SHPP has been widely studied. Thus, the purpose of this paper is twofold. Firstly, we present the improved version of the Cavallaro et al., [2018]’s method. Improvement aspects include formulas expression, calculation data, intuitionistic fuzzy matrix, entropy, weights and the weighted correlation coefficient. After the improvement, the ranking result of the various alternatives (ISHCC-1, ISHCC-3, ORC-1, ST-1, ORCREC-3, PT-3, PART-1, PART-3) is changed from “OREREC-3 ≻ PART-3 ≻ ISHCC-3 ≻ ST-1 ≻ ORC-1 ≻ ISHCC-1 ≻ PT-3 ≻ PART-1” to “OREREC-3 ≻ PART-3 ≻ ISHCC-3 ≻ ST-1 ≻ ORC-1 ≻ ISHCC-1 ≻ PART-1 ≻ PT-3”. Secondly, an improved fuzzy multi-criteria algorithm for optimizing concentrated solar power (CSP) hybridized systems based on Pythagorean fuzzy set is presented. Where, a new weighted correlation coefficient based on Pythagorean fuzzy set is proposed. On the one hand, the effectiveness of the proposed method is demonstrated by comparing with the different methods in the medical diagnosis application, which shows that the new method is as efficient as the other methods. On the other hand, we use the proposed method to re-rank differ solar power hybridized systems with the purpose of strengthening the ranking results. The re-ranking results we get are still: OREREC-3 ≻ PART-3 ≻ ISHCC-3 ≻ ST-1 ≻ ORC-1 ≻ ISHCC-1 ≻ PART-1 ≻ PT-3. It further indicates that the modified results given in this paper are correct. Furthermore, the proposed new sorting method based on Pythagorean fuzzy set is effective and reasonable. The refinement will help readers understand Cavallaro et al., [2018] well, and then apply intuitionistic/Pythagorean fuzzy multicriteria algorithm in related issues better.