This is a Biomass icon. We've made it in iOS style, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 12,600 icons, all in the same style and quality.
We've received the idea on January 29, 2013 and created the icons on April 04, 2013
Icons for green/renewable energy sources. The two I'm looking for are a Wind Turbine and Solar Panels. Other possible ideas are Hydroelectric, Geothermal, and Biomass, but those icons may be more difficult to portray with a simple icon.