This document discusses various types of green energy, including hydro, wind, solar, nuclear fusion, offshore wind, geothermal, and space-based technologies. It explains that green energy aims to minimize greenhouse gas emissions compared to fossil fuels. The types of green energy are described in detail, along with emerging technologies like smaller modular nuclear reactors, offshore wind farms, and tapping geothermal energy deep beneath the Earth's crust. The document concludes by noting technologies like space-based solar and hydrogen from the moon remain in development.