RNG can be derived from a variety of organic sources, with the most common being landfills, farms, and wastewater treatment facilities. Although the operations and technologies vary from project to project, the underlying fundamentals are the same. Biogas, which is comprised primarily of methane, naturally occurs in all of these settings. Without an RNG project, biogas historically has been either released to the atmosphere or flared (i.e., burned). Releasing it to the atmosphere is problematic because methane is a greenhouse gas which traps heat, thus leading to climate change. Flaring biogas is a waste of a renewable resource that can be used for heat, transportation, or electricity generation. Developing RNG projects at these sites is a way to help combat climate change and utilize a valuable fuel source that is already being generated naturally.