A gas inlet configured to convey a gas stream from a feed source to the system. A hydrogen sulfide removal stage includes a first vessel configured to receive a first media. A primary compression stage is configured to elevate a pressure of the gas stream. A moisture removal stage is configured to condense and separate remaining moisture from the gas stream. A siloxane removal stage includes a second vessel configured to receive a second media. A carbon dioxide removal stage includes a single-stage membrane configured to separate carbon dioxide from the gas stream by a permeability characteristic of the gas stream. A secondary compression stage is configured to elevate a pressure of the gas stream to a level suitable for distribution to CNG-compatible vehicles. An electrical generator set has a prime mover configured to be fueled by the gas stream.