Environmental Engineering Reference
In-Depth Information
Table 6.2
Breakdown of the Costs of Grid-connected Photovoltaic Systems
System size
1 kWp (%)
5 kWp (%)
Photovoltaic module
48
55
Inverter
13
13
Installation material
17
16
Installation (labour costs)
15
11
Planning / documentation
7
5
Source:
data from Becker and Kiefer, 2000
Hence, the average total annual cost
C
a
becomes:
(6.2)
Assuming that the system produces an average annual amount of energy
E
a
the
specific energy cost C
E
is calculated by:
(6.3)
This cost is also called the levelled electricity cost (LEC) or levelled heat cost
(LHC).
Costs for a photovoltaic system
Whereas average investment costs of
grid-connected photovoltaic systems
exceeded
10,000/kWh at the beginning of the 1990s, these costs have been
falling significantly. The cost reduction for photovoltaic systems has been
nearly 50 per cent per decade over the past two decades. End user prices for
single photovoltaic modules are now below
€
5/W
p
. Inverters, support
structures, cables and installation result in further costs. The specific
investment costs decrease with the system size. The end user prices for grid-
connected photovoltaic systems in the range of 5 kW
p
were about
€
7500/kW
p
€
in 2001, whereas prices close to
5000/kW
p
can be achieved for systems in the
megawatt size range. Table 6.2 shows that the photovoltaic modules make up
only about half of the total system cost.
The cost of one kilowatt hour of electricity generated by a photovoltaic
system is calculated here as an example. The underlying numbers have been
also used in the examples later in the chapter. The investment costs for a system
with a rated power of 1 kW
p
are assumed to be
A
0
=
€
6500. The operating
period of the system is 25 years (
n
= 25) and the system generates
E
a
= 800
kWh of electricity per year. This generation level can be expected in regions
with an annual solar irradiation of about 1000 kWh/m
2
, as found in central
Europe. In the tenth year of operation, one system component, for instance
the inverter, is likely to need replacing. This cost therefore is
A
10
€
=
1500.
€
