Active Thermal Cooling Technologies - Low Energy Cooling for Sustainable Buildings - page 125

Sarantis 700 kW

Uniklinik Freiburg 70 kW

Adsorption

Amberg 80 kW

Ineti 36 kW

Open
sorption

Ökopark Hartberg 30 kW

Mayer Althengstett 108 kW

IHK Freiburg 60 kW

Winery Banyuls 52 kW

Wolferts 92 kW

Ott&Spiess 35 kW

Absorption

Rethimo Hotel 105 kW

Fraunhofer Umsicht 58 kW

Office Inditex 170 kW

Trient 108 kW

0 1000 2000 3000 4000 5000 6000 7000

Total investment cost / per kW

Figure 5.9 Total investment costs for different solar cooling systems implemented in the last decade
in Europe

For some plants, details of the cost distribution are given. As an example, an absorp-
tion cooling systemwith a Yazaki WFC 10 installed at the Fraunhofer Institut Umsicht
in Oberhausen, Germany, is analysed. The system consists of 108m 2 of Soleado Lux
2000 VTCs, which are operated at design temperatures of 105/98 ◦ C at a nominal
efficiency of 69.6%. The cooling tower has 134 kW th at operating temperatures of
24/31 ◦ C, which are lowered with decreasing wet bulb temperature. The system also
has a heat storage of 6.6m 3 and a cold storage of 1.5m 3 . The total connected elec-
trical power including cold distribution is 10 kW, but usually does not exceed 3.5 kW
(Noeres, 2004). The distribution of costs is shown in Figure 5.10.
A more detailed analysis of investment and operating cost as a function of the
chosen solar cooling system design is carried out in Chapter 6. Some results from
the author's own projects on desiccant cooling systems will be presented in the next
section.

5.2 Desiccant Cooling

Desiccant cooling systems are an interesting technology for sustainable building
climatization, as the main required energy is low-temperature heat, which can be
supplied by solar thermal energy or waste heat. Desiccant processes in ventilation
mode use only fresh air, which is dried, precooled and humidified to provide inlet
air at temperature levels between 16 and 19 ◦ C. The complete process is shown in
Figure 5.11 with the fresh air side (dark heavy lines) and the exhaust air side (light
heavy lines). Outside air (1) is dried in the sorption wheel (2), precooled in the heat