There has been rejuvenation of interest by researchers in the development and enhancement of small-scale vertical axis wind turbines. (VAWTs) in recent decades. This emphasis is due to the recent increase in demand for less expensive, more environmentally friendly, and off-grid energy producing technologies. VAWTs are among one of the latest developments for small-scale power generation. Among the versatile available VAWTs, H-Darrieus can be studied under extensive exploration. VAWT was not gaining popularity because of its low power coefficient and the lack of attention shown by past researchers in it. Recent advancement in technology has opened door to study VAWT more precisely. Researchers demonstrated that the VAWT can be highly efficient with enhancements and slight modifications to existing designs and the right selection of gear trains. NACA 4412 blade profile is chosen as blade of the H-Darrieus rotor for our study. The objective of my work is to study and compare the power characteristics of standard NACA 4412 blade and external dimpled NACA 4412 profiles in H-Darrius turbine. The fabrication of model along with squared-shaped external dimples was done in the workshop. Before conducting the experiment at the exit of the subsonic wind tunnel available in the mechanical engineering department at NIT Silchar, external dimples were made at the locations of 25, 50, and 75% of the chord length at the middle of the span. Experimental result indicates the rise in performance of the H-Darrius rotor with external dimples on blade profiles performed better than the standard rotor of the blade profile at optimum location of 75 and 50%, 75% of the chord length for a single and two dimple configurations at a wind speed of 6 m/s respectively. Unfortunately, three dimples (25, 50, and 75% C) created a large wake area which led to an increase in the drag and therefore, there was a significant reduction in power coefficient for given TSR in comparison to the standard profile. The results of the experiments showed that adding external dimples to the rotor blade profile not only improved performance but also allowed for the maintenance of that performance throughout a wide range of tip speed ratios. Therefore, it can be stated that the H-Darrieus rotor performs better when square external dimples are present.