This is a concise book with comprehensive information on coal and biomass ash generated from their combustion in thermal power plants. It presents detailed studies on ash generated from contrasting coal and biomass feedstocks, and provides a comparative evaluation of these different ashes in terms of their origin, properties, environmental hazards. Potential utilizations with specific advantages and disadvantages of the respective ashes are elaborated in detail, including some innovative means of ash utilization for value addition purposes. By addressing both the theory and commercial exploitation of these products, this book will be helpful for industrialists, academicians and researchers alike.