The text discusses various technologies and methods that help in generating clean and renewable forms of energy. It also covers the use of fuels in energy conversion media such as internal combustion engines and compares these with existing fossil fuels. This book also focuses on green hydrogen revolution and the urban heat island effect. This book• covers topics such as sustainable biodiesel production, photovoltaic (PV) device optimization and performance enhancement, maximizing energy production, and improving the overall efficiency, reliability, and performance of solar energy systems. • explains energy-efficient green buildings, blue–green infrastructure, high building energy demand, solar chimney, urban green spaces in reducing the urban heat island effect, urban air quality, building resilience to airborne pathogens, and challenges related to urban green infrastructure. • discusses the carbon sequestration potential of urban parks, the evolution of carbon capture, utilization, and storage (CCUS) technology, hydrogen production technologies, production and utilization of hydrogen as a future fuel for electric vehicles, and the evaluation of carbon emissions from various vehicles. • presents solar-based thermal energy systems, optimizing solar air heater performance, and solar-integrated hydrogen production and utilization in India. • illustrates agro-residue-derived biochar for environmental management and competing alternative fuel technologies for commercial vehicles in India. The book is primarily written for senior undergraduates, graduate students, and academic researchers in the fields of mechanical engineering, environmental engineering, energy engineering, electrical engineering, electronics and communications engineering, automotive engineering, and renewable energy.