The evaluation of power electronics has emerged since last few decades ago. The advancement in the power engineering has made many advantages as per cost, performance and size point of view. In recent years, the power electronics is used in many aspects of commercial, utility, military, transportation, aerospace, etc. A part of power electronics is DC-DC converter, and it has applicability in computers, spacecraft units, laptops, telecommunications and motor drives. The photovoltaic based energy generation is the modern way of generating the energy and is adopted all over the world. But the efficiency in power generation by the photovoltaic system varies with the climatic condition. To achieve better efficiency, DC-DC converter can be used. The technique called maximum power point tracking (MPPT) helps in efficiency optimization. This paper presents the survey over the existing energy optimization techniques; further efficiency optimization for future study is mentioned.