Page 42 - Renewable Energy Devices and System with Simulations in MATLAB and ANSYS

Solar Power Sources: PV, Concentrated PV, and Concentrated Solar Power 29

Normal incident light

Mirrors Mirrors

Concentrated light
Si PV cell

FIGURE 2.13 A low-concentration PV setup using mirrors to concentrate light onto silicon PV cells.

FIGURE 2.14 An example of a concentrated PV system in Aurora, Colorado. (From National Renewable
Energy Laboratory, NREL, The Amonix 7700 Solar Power Generator is an example of a concentrating PV
system that is well-matched to utility-scale projects, Available: http://www.nrel.gov/continuum/utility_scale/
leading_solar.html, Retrieved on January 18, 2017.)

cost [24]. Nevertheless, concentrator PV technology is becoming even more competitive than some
other PV technologies [24] and it has great potential to take a significant share of electricity genera-
tion in the future energy source mix. The principle of CPV power generation is still based on the PV
effect. Thus, the electrical model is similar to that of the PV system, except for the expected irradi-
ance level and temperature that are much higher. However, due to the highly concentrated sunlight
hitting the small CPV cell, more thermal challenges come with the CPV technology, which have to
be addressed for each specific application [25, 26]. In order to accurately model a CPV application,
an electrical model linked to a thermal model of the PV setup is recommended.
One of the challenges in CPV is the high temperature that is associated with high-intensity light
hitting the PV cell. Consequently, CPV setups must have a proper heat sink system to dissipate
excess heat. As it can be seen in Figure 2.10, not only does high temperature decrease the voltage
characteristics of the CPV cell and the resulting output power, but it can also degrade the PV materi-
als more quickly than non-CPV cells. While there are a number of CPV installations throughout the
world [22], it is still an emerging technology that has not yet gained significant ground in the world-
wide PV system market. Figure 2.14 shows an example of a CPV system at the Solar Technology
Acceleration Center in Aurora, Colorado, USA, where 13 solar power generators have been installed.

2.4 CONCENTRATED SOLAR POWER

Concentrated solar power (CSP), also known as concentrating solar power, solar thermal power,
or solar thermal electricity, uses glass mirrors of different architectures to collect the sun’s ther-
mal energy and convert it into electrical energy. This is achieved via conventional thermodynamic