Synthetic natural gas

Renewable natural gas is a biogas which has been upgraded to a quality similar to natural gas. A biogas is a gas obtained from biomass. By upgrading the quality to that of natural gas, it becomes possible to distribute the gas to customers via the existing gas grid, and burned within existing appliances. Renewable natural gas is also known as Sustainable Natural Gas, and is a subset of Synthetic Natural Gas or Substitute Natural Gas (SNG).
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A manufactured product chemically similar in most respects to natural gas, resulting from the conversion or reforming of petroleum hydrocarbons. It may easily be substituted for, or interchanged with, pipeline quality natural gas.