This paper presents a detailed analysis on the viability of using alternate power methods for small multicopter Unmanned Air Vehicles (UAVs). Recently, fuel and solar cells have been successfully used to power autonomous winged UAVs for a wide range of applications, but alternate power supplies in multicopters have been much less explored due to increased power requirements compared with their winged counterparts. In this paper we discuss the theory and barriers to this technology along with ways multicopter UAV endurance can be theoretically increased by more than 50% using solar and fuel cells and how future advancements will quickly improve upon these numbers by more than 60% in the coming years.