Various definitions are presented for reliability, but the definition that is widely accepted is as follows; Reliability is the probability of a system or a component correct operation under exploitation condition in specified time [2].
Reliability calculations are major issues which should be considered along with economic and environmental evaluations resulting from using energy renewable sources. //Accurate evaluation of economic profit used from these units needs investigation of rate of systems` reliability. //Obviously, available energy limitation in renewable energy sources and also its discontinuous behavior reduces level of system reliability [3-5].