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SOLAR POWER SYSTEM PHYSICS

AND TECHNOLOGIES

Solar, or photovoltaic (PV), cells are electronic devices that essentially convert the
solar energy of sunlight into electric energy or electricity. The physics of solar cells is
based on the same semiconductor principles as diodes and transistors, which form the
building blocks of the entire world of electronics.
Solar cells convert energy as long as there is sunlight. In the evenings and during
cloudy conditions, the conversion process diminishes. It stops completely at dusk and
resumes at dawn. Solar cells do not store electricity, but batteries can be used to store
the energy.
One of the most fascinating aspects of solar cells is their ability to convert the most
abundant and free forms of energy into electricity without moving parts or compo-
nents and without producing any adverse forms of pollution that affect the ecosystem,
as is associated with most known forms of nonrenewable energy production methods,
such as fossil fuels, hydroelectric power, and nuclear energy plants.
In this chapter we will review the overall solar energy conversion process, system
configurations, and economics associated with the technology. We also briefly look
into the mechanism of hydrogen fuel cells. In addition, we will review the fundamentals
of solar power cogeneration design and explore a number of applications, including an
actual design of a 500-kW solar power installation project, which also includes a
detailed analysis of all system design parameters.

Brief History of the Photoelectric

Phenomenon

In the latter part of the nineteenth century, physicists discovered a new phenomenon.
When light is incident on liquids or metal-cell surfaces, electrons are released. However,
no one had an explanation for this bizarre occurrence. At the turn of the century, Albert

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