Kernel shell cellulose, kernel shell nanocellulose, and kernel shell nanocellulose residue synthesized from palm kernel shell were utilized as fuel for microbial fuel cells (MFCs) with Cellulomonas fimi. Commercially available cellulose (cellulose powder) was also tested to compare the performances of the MFCs. Kernel shell nanocellulose yielded the highest current generation, with a maximum current density of approximately 26.4 +/- 1.1 mA/m(2), followed by cellulose powder, kernel shell cellulose, and kernel shell nanocellulose residue, with current densities of 16.8 +/- 1.0, 15.0 +/- 1.7, and 11.9 +/- 1.5 mA/m(2), respectively. The current generation ability of the palm kernel shell was similar to the electrical performance of commercially available cellulose.