Renewable energy would become more topical as natural energy resources are depleted. Also a major global issue is the extent of solid waste generation of which biowaste is the main component and development of its bio-energy potential can address issues such as renewable energy and environmental pollution, simultaneously. Used paper is a primary component of biowaste with cellulose its dominant structural biopolymer. Various used paper materials have been treated with a cellulose hydrolyzing enzyme from Penicillium funiculosum to bioconvert their cellulose component into sugars such as glucose that could be utilized as feedstock for the synthesis of biodegradable products such as bio-ethanol. These paper materials exhibited nonsimilar susceptibilities toward this cellulase enzyme and consequently different sugar releasing and bioconversion efficiency patterns were obtained when changing quantities of each paper were treated with a fixed amount of enzyme. When a fixed amount of each paper material was treated with increasing enzyme concentrations, different bioconversion and efficiency profiles were also constructed for each paper material biodegraded.