Cloud computing is an evolving standard that delivers computing and storage possessions as a service over internet. One of the major key concerns in cloud computing is the high energy consumptionthe energy ingesting in datacenter of a cloud is on the increase, though the possessions are extremely underutilized, this offers a blockage that limits the development of cloud computing.Power administration strategies which goals to decrease total energy used up in data centers pose encounters in together tools and resource administration strategies the exact alteration of the estimators’ alignment restrictions has showed to substantial accuracy developments. Energy effectiveness and bandwidth ingesting of the system is in adding to enhanced quality of service QoS achieved as an outcome of the condensed intervals. In this paper we investigate about the problems that cause the high energy consumption and the techniques used in existing approaches to overcome high energy consumptions and to improve QoS. © Research India Publications.