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Numerous factors affect how well a solar PV system performs, and continuous monitoring of these parameters while it is in operation is necessary to suggest improvements and attain peak optimum performance. This study examines the impacts of irradiance, cell temperature, wind velocity, water cooling, and dust deposition are examined on a 50W PV module in Rajshahi, Bangladesh. Experimental results suggest that the preferred wind velocity and water flow rate for the PV panel's top surface cooling were around 5 m/s and 0.0045 m3/min (0.113 m3/min per m2 of panel area), respectively. The cooling system's water circulation at 0.0045 m3/min boosted the PV panels' output power, energy efficiency, and exergy efficiency by 20.47%, 12%, and 37.5%, respectively, at 730–780 W/m2 irradiation. The dust deposition of the PV panel reduced the power output to 21W from 46.81W (without dust) upon applying 42 gm of dust with a 0.29 mm particle size. Wind velocity (5 m/s) increases efficiency from 14.8% to 16.5%. The findings of this study may be useful to investors and policy makers in helping them to take right actions to minimize losses associated with the effects these operational and environmental factors.

The paper ascertains and presents alteration in the energy consumption as a consequence of utilizing the low-temperature waste streams commonly used in the lines of continuous dyeing at the finishing shops of textile enterprises of Belarus. The utilization realizes through the engagement of lithium-bromide absorption heat pumps with various energy characteristics such as the heating coefficient (relative conversion ratio COPhp = 1,15; 1,7; 2,2) and the heating capacity. The latter associates with the converted heat-flow energy utilization variant with the heat-transfer medium heating system scheme (one-, twoand multistage heating). The article considers transition to previously not applied service-water preheating due to the technological acceptance of feeding higher temperature water into the dyeing machine and widening specification of the heattransfer media. The authors adduce variants of internal and external energy use and their evaluation based on the relative energy and exergy characteristics. With results of the thermodynamic analysis of the modernized production effectiveness the researchers prove that alongside with traditional and apparent interior utilization of the energy associated with the stream heat recuperation, it is advisable to widen the range of applied heat-transfer media. The transition to the service water twoand multi-stage preheating is feasible. The study shows that the existing energy supply efficiency extremely low index-numbers improve by one or two degrees. Since they are conditioned, inter alia, by the machinery design, traditional approach to energy supply and heat-medium usage as well as the enterprise whole heating system answering requirements of the bygone era of cheap energy resources. The authors examine the continuous dyeing line modernization options intending considerable investments. Preliminary economic assessment of such inevitable modernization options for the enterprise entire heat-and-power system shows reality of meeting all going with the times requirements such as economic, environmental, energy for similar projects.

This paper presents a study on the possibility of recovering low thermal potential heat from the cooling technological water of industrial processes. The analysed solution consists in the use of a heat pump which would send the recovered heat to a hot water flow. We started from a technological water flow which was taken over by a 350 m3/h cooling tower and we determined the performances of a heat pump when using various refrigeration agents, for a range of values of the temperature of hot water and the temperature of the return of technological water which varies according to season.

Highlights: [•] Entransy analysis was made for irreversible heat engine and refrigeration cycles. [•] Entransy dissipations were defined and determined. [•] Relations between entransy dissipation and other thermodynamic parameters were determined. [ABSTRACT FROM AUTHOR]

This paper presents a study on the possibility of recovering low thermal potential heat from the cooling technological water of industrial processes. The analysed solution consists in the use of a heat pump which would send the recovered heat to a hot water flow. We started from a technological water flow which was taken over by a 350 m³/h cooling tower and we determined the performances of a heat pump when using various refrigeration agents, for a range of values of the temperature of hot water and the temperature of the return of technological water which varies according to season. [ABSTRACT FROM AUTHOR]