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Every year the renewable energy topic becomes more important. Kyrgyzstan, a small country in Central Asia, also attempts to develop green, environmental sources of energy. While the promotion of renewable energy in developed countries is considered as an additional energy source and simultaneously a "tool" for environmental protection, then in Kyrgyzstan as a developing country, it should be recognized firstly as a solution to the social problems. This paper presents the current situation of the renewable energy sector, including legislation, as well as academic education on "renewable energy". Kyrgyzstan has a large hydropower potential due to the landscape features, but only 10% of this water amount potential is used today. Utilization of energy from biomass as well as from solar energy is in an "embryo" stage, even though Kyrgyzstan is an agrarian country and has good solar radiation potential. The geothermal resources have good treatment properties, therefore they are successfully used mainly in health resorts and not for the extraction of thermal energy. Some examples will be presented in this paper. The influence on renewable energy market formation comes also from universities, where specialists are educated and trained. The universities in turn depend on the market demands. There are four universities in Kyrgyzstan that offer a specialization in renewable energies, particularly

Although solar drainback systems have been used for a long time, they are still generating questions regarding smooth functioning. This paper summarizes publications on drainback systems and compiles the current knowledge, experiences, and ideas on the technology. The collective research exhibits a lack of scientific publications dedicated to the drainback technology, however a significant number of patents have been published, detailing innovative technical solutions towards improvements and reliability. Based on the evaluation of drainback hydraulics, a detailed classification of this technology has been developed, with a brief description of each hydraulic typology. The operating modes have been split into three stages: filling, operation, and draining, which have been studied separately. A difference in the minimal filling velocities for a siphon development in the solar loop has been discovered in various reports. Specific features of the operation mode have been described. For the draining, existing mechanisms to initiate the emptying process have been identified and categorised. Finally, stateof-the-art hydraulic components for drainback systems have been established, with emphasis on their requirements. Based on those findings, the authors suggest potential future research paths in order to fill the knowledge gap and disseminate the drainback technology.

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