This book presents a comprehensive review of energy research studies from authors around the globe, including recent research in energy efficient appliances and energy efficient behaviors; renewable energy technologies and sustainable development; demand for clean energies efficient development in building technologies; recent advances in biomass and biogas development and perspectives; development and evaluation of a direct expansion heat pump system; assessment of the measured data with respect to renewable energy technologies; capacity of manets employing a continuous interference model with a propagation channel considering law of conservation of energy; assessing the sustainability of bioenergy systems; investigation of design parameters effect on power output and thermal efficiency of the stirling engine with irreversibility consideration using finite speed thermodynamics; energy saving and optimization of heat exchanger networks using an evolutionary method; and optimization of powered stirling heat engine with finite speed thermodynamics.