Design change is a common but significant problem in construction projects. Issues of delay, cost overruns, claims, and disputes in projects occur as a result. However, design change studies in the power-project area are less often discussed. As a result, the primary objective of this study was to identify important cause factors of design changes according to different power-project types in Ghana. Following a thorough assessment of the literature, 36 potential causes were identified, which were narrowed down by expert reviews to 30. In this study, power projects were classified into three categories: power plant, renewable, and distribution and transmission. The results indicate owner-related financial problems as the most important cause of design change for all three project types, followed by the second and third most significant in each of the categories, respectively: errors and omission in design and problems or unforeseen site conditions in power plant projects; deficient quality and quantity of resources and inflation and changes in interest and exchange rates in renewable projects; and problems or unforeseen site conditions and changes of plans in distribution and transmission projects. Based on the findings, power-project stakeholders are able to comprehend the dynamics of design change and develop effective design management strategies to reduce impact.