Review on Progress and Challenges of the Power Generation Systems at Micro-Scales

Abstract

The miniaturization of electro-mechanical devices, and the resulting need for micro-power generation (milliwatts to watts) with low weight, long life devices, has led to the recent development of the field of micro-scale combustion and power generation. The primary objective of this new field is to leverage the high energy density of fuels, specifically liquid hydrocarbon fuels relative to batteries and all other energy storage devices other than nuclear fission, fusion or decay. Some brief scaling arguments are given in this work, and more detailed efforts are referred. A brief introduction to several of the fabrication techniques is presented in this work. Hydrogen-based and some preliminary specialty fuel micro-fuel cells have been successfully developed, and there is a need to develop reliable reformers (or direct conversion fuel cells) for liquid hydrocarbons so that the fuel cells become competitive with the batteries. In this work, the technological issues related to micro-scale combustion and the development of thermochemical devices for power generation will be discussed. Some of the systems currently being developed will be presented, ongoing critical study issues under investigation, and other potential areas of development discussed. Comments regarding the opportunities and limitations of each of the techniques are also presented where applicable.