This chapter provides a comprehensive overview of various renewable energy technologies, excluding photovoltaic and concentrating solar systems (that are described in detail in Chap. 1, “Renewable Generation Technologies: Utilizing Solar Power” ), that are installed in active distribution networks. It delves into their underlying physical principles, operational mechanisms, and real-world applications. The chapter covers wind energy, hydroelectric power, biomass, and geothermal energy, each explored in detail to highlight their respective technologies, advantages, and challenges. Starting with wind turbines, the chapter explains the fundamentals of wind power generation, the origin and distribution of wind, and the mechanics of energy conversion. It also discusses different types of wind turbines, including their orientation, rotor design, and efficiency characteristics, along with the integration of electrical systems in wind farms and the environmental impacts associated with their operation. Hydroelectric power plants are examined next, with a focus on the different types of plants, such as run-of-river, pumped hydro storage, and hydro storage power plants. The chapter explores their functionality, advantages, and limitations, as well as the use of water turbines and ocean energy systems. Biomass as a renewable energy source is also considered, with emphasis on its production processes, types of solid, liquid, and gaseous fuels, and the energy potential of biomass systems. A thorough evaluation of the benefits and drawbacks of biomass usage is provided, including its role in sustainable energy solutions. Finally, geothermal energy is discussed in terms of both deep and near-surface geothermal systems. Advantages such as sustainability and low environmental impact are weighed against challenges such as resource location and initial investment costs. Through this exploration, the chapter provides valuable insights into how these renewable technologies—located in active distribution networks—contribute to the global transition to clean, sustainable energy sources, offering a balanced perspective on their capabilities and challenges.