Finding new energy sources has been a major quest in the 21st century. The challenge is not simply to find alternatives for traditional energy sources like crude oil and coal to generate power on a large scale but also to produce power to energize micro and nano scale devices. For electricity production in the nano and the micro scale, research has been done on technologies including fuel cells and batteries.This study is focused on two themes, i.e., the use of a microbial fuel cell and an enzymatic fuel cell for potential bioMEMS/NEMS applications. In the first , a fully functional fuel cell with yeast as the microbe using glucose as the fuel was tested to characterize its performance. In the second phase, a lactate dehydrogenase based enzymatic fuel cell using lactate as the fuel was tested to understand the performance characteristics.