Portfolio 21 does not invest in companies directly involved in the extraction and production of fossil fuels ─coal, oil, and natural gas. Natural gas has a lower greenhouse gas (GHG) emissions profile than either oil or coal. Despite natural gas’s lower GHG profile, it is a combustible mixture of hydrocarbon gases, formed primarily of methane. Deposits are found at varying depths beneath the Earth’s crust, both onshore and offshore, requiring the use of both conventional and unconventional extraction methods. Given the elevated environmental risks associated with extraction, Portfolio 21 will not invest in extraction and production. However, due to the current limitations of renewables (in terms of current capacity and financial attractiveness), and the lower GHG profile of natural gas, Portfolio 21 will invest in companies involved in the transmission and distribution of natural gas as well as in utilities that utilize natural gas as a fuel source.