Textbook in PDF format The primary focus of this contributed volume is on providing cutting-edge developments in a number of critically important fields, including energy, combustion, power, propulsion, environment using fossil fuels, and the production and use of biofuels. The availability of clean and sustainable energy is more crucial now than ever before for all areas of energy use in power, mobility, and propulsion. In the future, the energy used will only grow due to the increase in population and enhanced standards of living. This book includes contributions from globally recognized specialists from various regions of the world. They have provided the most recent advances in both basic and applied research on the creation of cleaner energy and its application for a variety of technologies, from microscale energy conversion to supersonic and hypersonic propulsion powered by hydrocarbon fuels. Clean and efficient energy conversion for various stationary and propulsion applications, including hypersonic propulsion, thermal management, emission control, and environmental issues for energy sustainability, are amongst the challenges and opportunities followed for the specific applications. In parallel, some of the other applications include the combustion of fossil and biofuels, clean energy production from low-grade materials such as waste and biomass, and alternative fuels via rigorous modeling and simulation, with a focus on efficiency and environmental issues. The present and future R&D activities include specially designed technical tracks and contributions from internationally recognized technical experts that reveal different but complementary viewpoints on fuels, combustion, power and propulsion, and air toxins. The development and implementation of novel energy conversion technologies require solid fundamental understanding, as well as research and development efforts at different scales, from bench to pilot to full scale. We conjecture that for the foreseeable future, hydrocarbon fuels will likely remain a major source of energy in all sectors of power, transportation, and propulsion, with a slow but steady increase in renewable energy resources in the overall energy mix. A multifaceted strategy is needed for the energy and environmental sustainability of all power and propulsion systems. This includes creating and utilizing alternative and renewable fuels, designing flexible fuel combustion systems that are simple to use with the new fuels, and developing cutting-edge, eco-friendly technologies to maximize the use of all types of gas, liquid, and solid fuels