Solar energy use in buildings - Solar Energy Sciences and Engineering Applications - page 612

Figure 18.10.4 Cooling load as a function of the window to floor area ratio to net area.

Figure 18.10.5 Typical cooling loads for buildings in Germany and offices in Palermo, Italy.

In the case of very high energy-intensive use, such as computer centres or server
rooms, the cooling loads could increase by up to 1000 W m − 2 , as demonstrated by
Figure 18.10.5.
The sum of external and internal loads leads to an average cooling load in admin-
istrative buildings of about 50 W m − 2 . The cooling load is dominated in many cases
by the external loads (see Figure 18.10.6).
Air-conditioning in non-residential buildings is often more important than heating
even in moderate climates. Air-conditioning in buildings and refrigeration is respon-
sible for about 15% of total energy consumption worldwide, and in hot and humid
climates for 30%. Cooling energy is often required in commercial buildings, the highest
consumption worldwide being in the USA with up to 150 kWh m − 2 a − 1 , and val-
ues quoted between 20 kWh m − 2 a − 1 for Sweden, 40-50 kWh m − 2 a − 1

for China and

61 kWh m − 2 a − 1 for Canada.
Our own overview of the cooling energy requirement of different building projects
shows a typical cooling energy consumption for administrative buildings of between
20 and 60 kWh m − 2 a − 1 in Europe, as shown in Figure 18.10.7.