Renewable natural gas (RNG) is derived from biomass or other renewable resources, and is a pipeline-quality gas that is fully interchangeable with conventional natural gas. The American Gas Association uses the following definition for RNG:

Pipeline compatible gaseous fuel derived from biogenic or other renewable sources that has lower lifecycle carbon dioxide equivalent (CO2e) emissions than geological natural gas. 

The primary objective of this report is to characterize the resource and economic potential for RNG as a greenhouse gas (GHG) emission reduction strategy. Further, this report seeks to improve policy makers’ understanding of the extent to which delivering RNG to all sectors of the economy can contribute to broader GHG emission reduction initiatives.

The following sub-sections introduce the RNG production technologies and corresponding feedstocks. ICF assessed the production potential for renewable gas into three categories: 1) RNG from renewable feedstocks using anaerobic digestion (AD) and thermal gasification (TG), 2) RNG derived from municipal solid waste (MSW), and 3) RNG produced via combination power-to-gas (P2G) and methanation. For each resource and production technology pairing, ICF estimated the production cost and corresponding range of GHG emissions.