Page 214 - Applied Photovoltaics

7. Environmental benefits of 155 tons of CO 2 and 0.5 tons of NO x avoided per
year were evaluated at US$31–34/kW/year.
8. Minimum load savings from avoiding the marginal costs of keeping peak
load-following plant online.

10.6.5 Example 2—Kalbarri, Western Australia
Kalbarri is a town 500 km north of Perth at the end of a 136 km distribution line at
the northern extreme of the main power grid in Western Australia. This project aimed
to demonstrate and investigate PV grid support, test inverter technology, and provide
experience with PV trackers and inverters (Jennings & Milne, 1997; CADDET
Australian National Team, 1998). 20 kW p of PV modules are mounted on 16 single-
axis trackers, each with 16 modules. A 35 kVA three-phase current-controlled power
inverter and a 100 kVA transformer connect them to the grid, which was subject to
voltage fluctuations.
The Kalbarri peak load was dominated by air conditioning and occurred in summer,
typically in afternoons or early evenings, while the PV tended to peak around 2.30
pm. The PV system was not expected to have a significant effect on the 3 MW peak
load and was too small to have an impact on the town’s voltage stability, but it does
provide real-world data on PV potential.

10.7 INTERNATIONAL PV PROGRAMS
Electricity costs are almost universally subsidised to various extents, including by
direct financial subsidies for social or other reasons and by externalisation of the costs
of environmental damage (Kjaer, 2004; Riedy & Diesendorf, 2000; European
Environment Agency, 2004; Schmela, 2003; Pershing & MacKenzie, 2004). One
estimate of global annual energy subsidies over the period 1995–1998 was US$244
billion, of which just 3.7% was attributed to renewables and end-use efficiency
(Pershing & MacKenzie, 2004). This ‘market failure’ makes difficult the entry of
new, small players. It is not socially or politically feasible to suddenly remove such
subsidies to conventional energy sources, so a commonly applied ‘second-best’
alternative is to offer support to new market entrants with perceived advantages to the
community. Kjaer (2004) describes how either prices or quantities of renewable
energy may be controlled, and compares the methods in the European context. An
overview and detailed discussion of national policy instruments is provided by Sawin
(2004), while strategies used to support PV are discussed in Haas (2002).

10.7.1 USA
During the 1970s and 1980s, the US Department of Energy implemented a pioneering
residential PV research, development and demonstration program to monitor
household loads, evaluate and provide technical information on residential PV
systems in different regions, build and monitor isolated PV powered homes, clusters
of homes (e.g. 30 homes) and commercial buildings, and to assess impacts on the
power distribution network (see Fig. 10.12).

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