protection against overheating of premises, cooling of air, domestic water supply, energy efficiency, solar radiation, energy saving, conservation of the environment


Problems. Windows in the summer let through a large amount of solar energy into the room, which causes an additional cost of cooling the air by conditioning. It is known that the limit of comfort is the temperature of 26 oC. To reduce the temperature, use air conditioners, which are required 0,3...0,5 kW of electrical power for 10 m2

of housing. The study deals with the capture of solar energy by water and its use for domestic water purposes (DHW).

The goal of the research. Experimental verification of patented developments and calculations of hot water quantity obtained per day, energy savings and economic indicators.

Methods of implementation. Experiments were conducted on the south window of the room, with water pumping by a pump and periodic measurement of air and water temperatures at the outlet of the system by mercury thermometer. The calculations were performed using the methods developed by the authors. The studies were conducted within three days of November. The temperature inside ranged a room from 19 to 23 °C. The system was operated in circulating mode on a water battery tank located below the absorber. Isolation of the absorber from the side of the room was made of a transparent food film.

Research results. Water temperature reached 45 °C per 1,5-2 hours. Water consumption is enhanced by the thermosiphon effect when water moves from the bottom up. On a clear day of spring and autumn, you can heat for 50-70 % more water than the average for the average day of months of the warm season. For preparing DHW with 1 m2 of absorber, it is possible to get 45-50 kW∙h of heat for each month from March to September, taking into account cloudiness. The savings from the use of hot water and from reducing the consumption of electricity in the air conditioner are calculated.

Conclusions. The payback period of the system, taking into account the cost of the heat for DHW and electricity savings for an electric air conditioner, is approximately 4-5 years. The cost of the system is close to the cost of a home air conditioner, for a premise with a single window oriented south. To the energy-saving factor, an additional advantage is the environmental friendliness of the system compared to the air conditioner.


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