This latest volume includes contributions on the latest advances in energy research. Chapter One discusses heat transfer in micro-ducts. Chapter Two addresses the description and analysis of volume holographic elements for solar concentrating systems based on the detailed simulation of the energy amount and profile along with the spectral distribution delivered onto the solar receiver. Chapter Three reviews the impact of using thin alloyed capping layers (CLs) for InAs/GaAs quantum dot (QD) solar cells. Chapter Four examines the development of soap based thermal insulation for buildings as a sustainable alternative to the petroleum based counterparts, whilst decreasing the associated environmental costs. Chapter Five analyzes the simulation of spark plasma sintering for the preparation of inhomogeneous thermoelectric materials for energy generators. Chapter Six proposes a new maximum power point tracking algorithm for generators based on the suggested accurate electro-thermal model for them. Chapter Seven focuses on signal processing based mechanical fault prognosis and diagnosis of operating wind turbines in wind farms.