Energy Demand of Buildings - Low Energy Cooling for Sustainable Buildings - page 12

2006). If about 60 kWh m − 2 a − 1 is subtracted for lighting (survey, US Department
of Energy, 2002) and 50 kWh m − 2 a − 1 for cooling, this corresponds to an average
electricity consumption for equipment between 55 and 110 kWh m − 2 a − 1 .
Lighting Energy Consumption
Lighting energy contributes typically less than 10% of the total end energy consump-
tion in residential buildings: for example, about 500-770 kWh per household in Spain
and about 3% of electricity consumption in the UK (Ashford, 1998). In office buildings
lighting often dominates the total electricity consumption (36% of the electricity con-
sumption for offices in Germany and about 20% of electricity consumption in the UK
commercial/public sector). The lowest values measured are around 5 kWh m − 2 a − 1
and can rise as high as 50-70 kWh m − 2 a − 1 for banks or commercial buildings in the
UK and the USA (BINE, 2000). For the ZUB office building in Kassel, Germany,
with fa¸ade high windows, a low room depth of 4.6 m and daylight-dependent arti-
ficial lighting control, average lighting electricity consumption of 3.5 kWh m − 2 a − 1
was measured during an intensive monitoring exercise (Hauser et al ., 2004). A survey
of lighting electricity demand or consumption has been carried out by the author and
is shown in Figure 1.12. It includes measured data from office building projects like
the Lamparter building, the ZUB Kassel and several case studies from the UK, the
USA, Germany, etc.
Figure 1.12 Lighting energy consumption in office buildings