Solar energy has also experienced an impressive technologi-
cal shift. While early solar technologies consisted of small-scale
photovoltaic (PV) cells, recent technologies are represented by
solar concentrated power (CSP) and also by large-scale PV sys-
tems that feed into electricity grids. The costs of solar energy
technologies have dropped substantially over the last 30 years. For
example, the cost of high power band solar modules has decreased
from about $27,000/kW in 1982 to about $4000/kW in 2006; the
installed cost of a PV system declined from $16,000/kW in 1992 to
around $6000/kW in 2008 [5,6,7]. The rapid expansion of the solar
energy market can be attributed to a number of supportive policy
instruments, the increased volatility of fossil fuel prices and the
environmental externalities of fossil fuels, particularly greenhouse
gas (GHG) emissions.