The process of evolution in the computation methods used in the energy harvesting techniques in MISO cognitive radio networks is thoroughly studied. It involves two users the licensed User (primary user) and the Non-licensed (secondary user). The hybrid base station (HBS) is the network involves with both the PU and SU. Secondary user consists of multiple antennas which are used to harvest energy from hybrid base station. Nakagami-m fading channel is used to transmit the data in uplink and downlink. Asymptotic formula is used to derive signal to noise ratio and also average system error probability and ergodic capacity which could be formulated using the closed form expression. In this paper, black widow optimization technique is used to find fitness value of population. Moreover, black widow method is used to minimize outage probability and also in identifying the optimum secondary user transmission power. Black widow optimization works on the principle of the evolution methodology of the black widow spider and its mating behaviours. This meta heuristic algorithm is used to validate the mathematical analysis.