Page 213 - Applied Photovoltaics

The economic benefits of the photovoltaic array, in 1995 US$/kW/year, were then
estimated and the results are graphed in Fig. 10.11.

Figure 10.11. Value of Kerman PV plant to utility company in 1995 US$/kW/year
(©1994 IEEE, adapted from Wenger et al.).

In summary, the benefits identified were (Wenger, 1994):
1. Energy benefits based on avoided fuel costs, valued at US$143–
157/kW/year.
2. Capacity credit based on the avoided cost of provision of extra capacity to
improve reliability and valued at US$12–53/kW/year.
3. Reduced ohmic and reactive power losses reduced by 58,500 kWh/year and
350 kVAR, since less power had to be transmitted, resulting in savings of
US$14–15/kW/year.
4. Substation savings reflect the savings from the extension of the life of the
10.5 MVA distribution transformer by reducing its peak temperatures
($89/kW/year) and reduced maintenance on the load-tap-changer (fewer tap
changes). Together, these contributed US$16–88/kW/year.
5. Transmission benefits are similar in concept to the capacity credit value but
reflect the cost of avoided investment in the distribution system and its
maintenance. They were valued at US$45/kW/year.
6. Reliability benefits reflect the economic savings to customers that would
result from more rapid load recovery after a circuit outage with the PV plant
present. A value of about US$4/kW/year was estimated as a saving to the
utility but further benefits accrue to customers. Improved reliability is of
economic benefit to utilities since it reduces pressures to upgrade. Voltage
support of about 3 V was found to be predictable.

200