Solar Energy Perspectives - IEA

Solar Energy Perspectives: Buildings
and tilt of the collecting surfaces in relation to the available solar irradiance, and an efficiency
ratio of 10%, which represents the low end of PV efficiencies (Table 4.1). This technical
potential assessment does not account for the issues of variability and cost (IEA-PVPS, 2002).
Figure 4.10 Daily production of a 20 m 2 -PV roof and appliance electricity consumption
of small family in sunny region
Daily PV
electricity
output
Electrical
appliances
consumption
kWh/day
16
14
12
10
8
6
4
2
0
March
July
September
December
Source: Sunrise project/EPIA.
Figure 4-10
Key point
PV production on individual houses can cover the electricity consumption of appliances.
Table 4.1 Potential for solar electricity generation on buildings as share
of electricity consumption in 1998
Australia Austria Canada Denmark Finland Germany Italy
46.1% 34.7% 30.6% 31.6% 19.4% 30.1% 45.0%
Japan Netherlands Spain Sweden Switzerland
United
Kingdom
United
States
14.5% 32.2% 48.0% 19.5% 34.6% 30.7% 57.8%
Source: IEA-PVPS, 2002.
Key point
Building-integrated or -adapted PV can cover from 15% to 58% of electricity loads.
The achievable levels of generation depend mainly on the building areas available, solar
irradiance and electricity consumption. They are highest for the United States, and lowest for
Japan, mostly as a result of the available building area per capita. This building area includes
residential and commercial buildings, but also agriculture buildings and industrial buildings.
Their proportions vary from country to country, but residential comes first with more than half
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© OECD/IEA, 2011