abstract nowadaysphotovoltaic solar cells (pvs) areacknowledged the fastest growing energy technology in the word, however, they only account for only fraction of current global renewable energy capacity. it isrecognized that this incomplete market penetration has been largely a result of the technology’sexcessive cost. so researchers are trying to find innovative, economic way with theaim of either cutting back on the active material quantity or improving power efficiencies to abateoperating cost.however, have presented a cost.performance trade-off, that some believe may be surmounted by the employment of nanotechnology. amongst many potential nano-materials proposed for pv conversion is the carbon nanotube (cnt) due to its lowmaterial usage, superior carrier transport properties and most notably; a tunable band-gap. thisthesis examines the theoretical performance of a range of cnt based solar cells and in doing so, computational methodologies are formulated towards characterizing the related electronic andoptical properties with respect to the cnt structural variability. in this thesis addresses the issue of differentiation of metallic and semiconducting cnts. the result, a simulation-efficient and experimentally validated analytical model is developed to distinguish the nanotubes and predict the band-gap of semiconducting cnts.it offers a valuable insight into the optimization of cnt diameter related process parameters towards suppressing electronic mutability. the end part of this thesis focuses on modeling the optical absorption of cnts where thephoto-generated current and quantum efficiency responses are derived for various tube geometrieswhen exposed to laser illumination. the appointed models are later exploited in combination with anequivalent pv circuit model to evaluate the performance metrics of a variety of isolated cnt based pvdevices under solar radiation. within the confines of the suppositions made in this study, the result that only specific types ofcnts may yield competitive pv conversion efficiencies compared to other nanotechnology based solarcells.