The study presents the summary of the knowledge of energy-active segments of steel buildings adapted to obtain electrical energy (EE) and thermal energy (TE) from solar radiation, and to transport and store TE. The study shows a general concept of the design of energy-active segments, which are separated from conventional segments in the way that allows the equipment installation and replacement. Exemplary solutions for the design of energy-active segments, optimised with respect to the principle of minimum thermal strain and maximum structural capacity and reliability were given [34]. The following options of the building covers were considered: 1) regular structure, 2) reduced structure, 3) basket structure, 4) structure with a tie, high-pitched to allow snow sliding down the roof to enhance TE and EE obtainment. The essential task described in the study is the optimal adaptation of energy-active segments in large-volume buildings for extraction, transportation and storage of energy from solar radiation.

The blustery growth of high data rate applications leads to more energy consumption in wireless networks to satisfy service quality. Therefore, energy-efficient communications have been paid more attention to limited energy resources and environmentally friendly transmission functioning. Countless publications are present in this domain which focuses on intensifying network energy efficiency for uplink-downlink transmission. It is done either by using linear precoding schemes, by amending the number of antennas per BS, by power control problem formulation, antenna selection schemes, level of hardware impairments, and by considering cell-free (CF) Massive-MIMO. After reviewing these techniques, still there are many barriers to implement them practically. The strategies mentioned in this review show the performance of EE under the schemes as raised above. The chief contribution of this work is the comparative study of how Massive MIMO EE performs under the background of different methods and architectures and the solutions to few problem formulations that affect the EE of network systems. This study will help choose the best criteria to improve EE of Massive MIMO while formulating a newer edition of testing standards. This survey provides the base for interested readers in energy efficient Massive MIMO.