The article analyzes approaches to ensuring the energy efficiency of systems of different levels of integration: from the micro to the macro level. It is shown that depending on the level of the system under consideration, it may vary in the performance indicators they exhibit. Therefore, efforts to increase energy efficiency must differ in how they aggregate qualitatively different levels of energy consumption. It is illustrated that there is a difference of views and approaches between researchers who specialize in the issue of energy efficiency. In particular, representatives of exact sciences focus attention on the quality of input and output energy, while the economic perspective allows taking into account the levels of other costs as well and indicates economic efficiency, maximization of benefits and the efficiency with which energy resources are used. Arguments are presented in favor of the presence of a significant gap between the actual efficiency of energy consumption within the defined research objects and the efficiency that can be achieved taking into account the identified potential. As a result, individual households and enterprises do not invest in cost-effective energy-efficient technologies compared to what is optimal for achieving private or social effects. It is indicated that the achievement of this effect requires the coordination of efforts of various stakeholders (governments, businesses, researchers) and the development of joint approaches regarding the indicators of the success of the implemented changes. It is shown that several approaches have been developed in recent decades to implement policies to increase energy efficiency and stimulate energy-saving measures. Predictably, these approaches differ depending on the country and macro-region. They can provide for measures of a stimulating nature (with the involvement of the entire instrument of state regulation), and be based on the maximum freedom of choice of the consumer. It was determined that the interdependence and partial interchangeability of various factors of production, the numerous possible solutions to the problem of increasing the energy efficiency of systems of different levels of integration require the use of an interdisciplinary approach.