Fig. 4 shows a comparison of the cooling demand of the server room and the building itself. On the left hand side, caused by the constant heat input of the data processing equipment, a relatively constant demand over the year can be observed for the server room. In the present case, the demand is about 20 times higher than the cooling demand of the building. On the left hand side, the remaining cooling demand for the server is shown when the free cooling scheme using ambient air is applied. It can be seen that the demand for cooling the server room can significantly be reduced to almost 1/3.

In addition to the distinctive reduction of the cooling demand, the variation of the demand over the year has changed significantly, too. It can be seen that the cooling demand is mainly remaining during the summer months and is completely removed during winter times. Thus, with this change of the profile, an integration of a solar thermal driven air conditioning system seems to be possible.

Fig. 4: Comparison of cooling demand for the building and the server room. On the left hand side, the total
cooling demand resulting from the heat input of the server is presented, on the right hand side, the remaining
cooling demand for the server when using fresh air cooling is shown.