decreasing costs and prices. This decline has been driven by
1) efficiency increase of solar cells; 2) manufacturing
technology improvements; and 3) economies of scale [3]. In
the case of an autonomous street lighting system, the best
solution is the solar energy option, because of the long
lifetime, easy installation, and modularity.
The main lamp types used in street lighting are the high
pressure discharge lamps, e.g.: mercury vapor lamps, HPS
lamps, and metal halide lamps. The discharge lamps demand
a ballast that provides their starting and steady state behavior,
which is commonly electromagnetic [4].
Lighting emitting diodes (LEDs) are being presented as an
alternative to replace the conventional lighting systems.
Besides their use as signalizing systems is much broadcasted,
they are not commonly used as lighting systems. However,
recent technology is improving gradually the LEDs
efficiency and color quality, which allows their application in
lighting systems [5].