This research article published by Wiley & Sons Ltd, 2022Micro-hydropower can be used to meet the needs of both isolated and rural com munities for electricity. Due to its inexpensive initial investment, simple design, easy maintenance and low-head utilisation, the gravitational water vortex power plant (GWVPP) has recently piqued interest. The findings of numerical work employing a numerical simulation and analytical approach for the GWVPP are presented in this study. To understand the influence of each on the efficiency of GWVPP, four parameters (speed, hub-blade angle, number of blades and run ner profile) were explored. Design-Expert software was used to investigate the interplay of each parameter/factor in order to maximise the contribution of each. Design-Optimal Expert's (custom) design tool was used to construct twenty-four experimental runs. To calculate the system efficiency, these runs were simulated in commercial computational fluid dynamics (CFD) software called Ansys CFX. The numerical results were in good agreement with the experimental results, which yieldedR2 values of 0.9507 and0.9603 forflat andcurvedprofiles,respectively.Furthermore, the findings show that the chosen parameters have an impact on the GWVPP's efficiency via interaction as seen in response surface methodology (RSM). Furthermore, numerical analysis increased the curved blade profile runner's total efficiency by 3.65%. In compari son with the unoptimised scenarios, the efficiency of the flat runner profile increased by 1.69%.