What does the Acronym PV stand for?
PV = Photovoltaic
a.k.a Solar Electric Panel, Solar Photovoltaic Panel
PV is the term used in the solar industry to shorten the tongue-twisting word Photovoltaic, which describes a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect (Photovoltaics, 2012). The photovoltaic effect is how electricity (voltage and current) is generated from light. The term is often used in the context of PV Panels, PV Modules, or PV Systems.

References
“Photovoltaics.” Wikipedia, The Free Encyclopedia. Wikimedia Foundation, Inc. 12 Jan 2012. Web. 22 Jan 2012.