Solar Protocol is an experimental web platform hosted across a network of solar-powered servers, installed and maintained by volunteers in different locations around the planet. Although a solar-powered server’s connectivity is intermittent as it is powered by available sunlight, when connected in a network, the network can be designed to direct web traffic to whichever server is enjoying the most sunshine at the time. In doing this, Solar Protocol uses the distribution of sunshine across the planet as a form of logic that determines where computational work is done. By automating decisions according to environmental dynamics, the project explores a kind of "natural" intelligence rather than artificial intelligence. Solar Protocol works in concert with limits defined by local energy availability and thereby explores an energy-centered design. We sketch out six principles of energy-centered design, offering these as provocations for further work.