Exploration and research on new sources of energy are conducted continuously. These include the possible energy harvesting from renewable energy, including biomass. Among available biomasses, algae are considered to have very high potential due to their characteristics. Advanced energy harvesting from algae, especially for power generation, with significantly high energy efficiency are described in this book. To achieve significantly high energy efficiency, the idea of combining both exergy recovery and process integration (called as enhanced process integration, EPI) has been proposed and described. In exergy recovery, the quality of the recirculated energy remains the same, and the recovered energy can thus be used as an energy source for the subsequent process. As a result, almost all energy involved in the process can be recovered effectively and the total energy consumption can be reduced.To use the unrecoverable energy (heat) in a certain process, the idea of process integration is introduced, where the unrecovered energy (heat) from one process is used in other processes. Hence, the total energy loss in the integrated processes can be reduced.