From the category “creative responses to environmental challenges“: The Gravity Light. GravityLight is a revolutionary new approach to storing energy and creating illumination. It takes only 3 seconds to lift the weight which powers GravityLight, creating 30 minutes of light on its descent. For free. The makers of the Gravity Light started the project searching for options on how to bring affordable and sustainable energy and light source for places outside the power grid. They experimented with more conventional approaches utilizing solar technologies, but they ultimately came up with this quite ingenious invention: