This book provides a thorough introduction to lignite (brown coal) and subbituminous coals and explores how they can be used efficiently and economically in place of hard coal. The book examines the undesirable characteristics of low-quality coals, such as high moisture content, low calorific value, and aggressive ash characteristics, and the resulting refinements to standard technologies and practices required for successful combustion, gasification, and pyrolysis. It is a valuable resource for power generation engineers and researchers seeking to maximize the opportunities provided by these cheaper coal feedstocks for efficient and environmentally compatible power generation.