The Eco Whisper Turbine stands 21.1 m high and can achieve high energy outputs in low or high winds with a footprint of only 21 m2 (solar requires 250 m2) and is purposed for mid-sized applications of 20 kW. Did we mention that it's silent?

While the sun is abundant in more places, having a wind turbine can be a good supplement to producing free energy. In this guide, Ebert elaborates on the the different components of a wind turbine (blades, mount, generator) and how to go about building such a thing. Image source