In this paper, a high step up DC-DC converter with high efficiency is proposed that is applicable for low voltage renewable energy resources (RERs) such as photovoltaic (PV) and fuel-cell (FC). Input side series inductor guarantees continuous and low ripple input current that is necessary for maximum power point tracking (MPPT). Proposed topology consists of coupled inductor technology and an intermediate capacitor that lead to high voltage gain of the converter. A passive clamp circuit recovers the reserve energy of leakage inductor, reduces voltage stress on power switch and therefore reduces overall converter losses. Proper duty cycle value besides the leakage inductor decreases the reverse recovery problem of diodes. Small number of turn ratio of the coupled inductor in this topology causes lower leakage inductor and reduction in the volume and cost of overall system. Operation principles of the proposed converter are discussed in detail. Simulation results and experimental prototype validate the proper operation of proposed topology.