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Bachelor's thesis Christoph Kl÷pping

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Analysis of the operating performance of fašade ventilation units

BT C. Kl÷pping Copyright: EBC Fašade ventilation unit

This paper analyzes the operating performance of the fašade ventilation units of the main building of the E.ON Energy Research Center. Therefore, the stored data of the database is evaluated for the built-in fašade ventilation units of 72 offices in year 2013.

The fašade construction of the main building is responsible for the increased fresh air temperatures. The southeast and southwest fašades heat the fresh air most. Thereby, the fresh air increases on warm summer days up to 13 ░C and in winter up to 25 ░C above the temperature of the outside air. Heat power, up to 750 W, transported in the fašade ventilation unit, result from these increases of temperatures. This indicates that a huge amount of fresh air is heated along the fašade. A fašade remote air intake could reduce the fresh air temperatures.

The heating and cooling requirements of the concrete core activation are compared to the requirements of the fašade ventilation units. The concrete core located in the ceiling heats the o‑ces in winter and cools them in summer. In relation to the heating and cooling options of the fašade ventilation units, it becomes apparent that they partially work reverse.

The fašade ventilation units cool with an average fresh air temperature of 14.6 ░C. That implies that the fašade ventilation units use 34 % of the year with sucked in fresh air to cool the offices. This saves energy in comparison to water cooling. However, the amount of required cooling means that a large proportion of generated heat is carried into the environment unused. An adjusted concrete core activation could reduce energy consumption.

The air quality is evaluated by CO2 and VOC concentrations. Thereby, the measured CO2 values reveal an average room quality. The VOC concentration exhibit high values. These could attribute to the observed sensor-drift. In this case, it is ventilated more frequently and an additional energy requirement arises. A recalibration of the sensors could reduce the VOC concentration.