As the evidence of global warming continues to build up, it is becoming clear thatrnwe will have to find ways to produce electricity with out the release of carbondioxidernand other green house gases. Fortunately, we have renewable energy sourcesrnwhich neither run out nor have any significant harmful effects on our environment.rnHarvesting energy directly from the sunlight using photovoltaic (PV) technology isrnbeing widely recognized as an essential component of future global energy production.rnIn this thesis, intensity dependence and a brief over view regarding photovoltaicrnproperties of polymer based bulk heterojunction solar cell is presented and discussed