Utredning av solenergi för drivning av sorptiv kylprocess för inomhusluften på Stockholmsarenan

Cooling down the indoor air can be done in several ways. One way is desiccantcooling which will be used at the Stockholm Arena. This method is used in airhandling units that use temperature changes and moisture fluctuations in the air. Oneof the steps is to add heat during the cooling process in order to reduce the relativehumidity of the exhaust air. The air passes thru an adsorptions rotor which thenabsorbs moisture from the supply air. This results in the closing stages that the supplyair temperature drops when hydrating and the result is a cooler indoor temperaturethan the outdoor. This report is a result of a diploma work in building construction at UppsalaUniversity and is written as a guide for the Stockholm Arena to reduce theconsumption of purchased thermal energy, with the aim of producing its own energy.This is reported from a technical perspective, focusing at the design of a propersystem. Heat energy is today planned to be brought from district heating. It couldthou be replaced by other alternatives such as solar panels. To determine this, itinvestigates whether and to what degree solar panels can replace the district heat atthe cooling process of the indoor air from a technical perspective. This has beenimplemented with literature studies and interviews and further on calculations ofenergy but also financially by the annuity method. The case is focused on the summer conditions when the sorptive refrigeration willbe used. According to that calculations and assumptions have been made for probableenergy consumption and production. There after the investment costs weredetermined. The results gave that flat glazed solar collectors had a lower cost based on theenergy production but it required a much larger area than the vacuum solarcollectors. Based on the investment cost, vacuum solar collectors would be lesseconomi-cally significant. Further analysis showed that the solar panels took up almost the same amount ofarea whether of choosing them to stand free or be placed right on the roof. Theinvestigations of the operating temperature of the heating coil gained 60 degreesCelsius to optimize the performance. The size of the storage tank should not exceed3 cubic meters to obtain adequate energy changes. Solar energy is added to the tankat an external heat exchanger. At times when the heat input from the solar panels islower than required the district heat is the most appropriate kind to provide externalheat. This heat is given to the hot water slope leaving the tanks so it won’t disrupt theenergy output from the solar panels. In converted case where the production of heatis greater than required the heat energy can be used for hot water production.