Geothermal Cooling - Low Energy Cooling for Sustainable Buildings - page 101

Figure 4.21 Temperature levels and volume flows of activated concrete floor with fixed supply tem-
perature of 18 ◦ C to the room
temperature spread between ground heat exchange return and supply is 3 K on aver-
age and thus slightly higher than in the case of ventilation use. Increasing the pump
power could decrease this temperature spread and thus the surface temperature by
1or1 . 5 K further, but this would not significantly increase the cooling power (see
Figure 4.21).
The measurements were repeated during summer 2006 and very similar perfor-
mance was obtained (see Figure 4.22).
Figure 4.22 Power dissipated per metre of ground heat exchanger for the two operating modes of floor
cooling and ventilation system supply in summer 2006