Page 14 - Applied Photovoltaics

INTRODUCTION

Photovoltaics is the process of converting sunlight directly into electricity using solar
cells. The first photovoltaic device was demonstrated in 1839 by Edmond Becquerel,
as a young 19 year old working in his father’s laboratory in France. However, the
understanding and exploitation of this effect was to depend on some of the most
important scientific and technological developments of the 20th century. One is the
development of quantum mechanics, one of the major intellectual achievements of the
20th century. Another, dependent on the first, is the development of semiconductor
technology, which has been responsible for the pervasive electronics revolution and
the photonics revolution now gathering pace. An interesting history of modern
photovoltaic developments is given by Loferski (1993) and the early history, reaching
back to 1839, is described in more technical detail by Crossley et al. (1968).
Fortunately, given its pedigreed background, the simplicity and reliability of use of
solar cells is one of the technology’s great strengths. In the first few chapters of this
book, we explore the properties of the two most important components of this
process—sunlight, which provides the primary source of energy, and the solar cells
themselves, which convert this sunlight by elegant internal processes into electricity.
We then look at the fabrication of cells and modules before examining a range of
photovoltaic systems, from specific purpose applications such as solar cars through
independent power supplies for households or water pumping to large grid-connected
power stations.