SCS Energy: LFG to CNG as Vehicle Fuel in Sonoma

Sonoma LFG to CNG 

The Sonoma LFG to CNG Project was a pilot scale RNG plant that converted LFG to CNG for use as vehicle fuel. The RNG plant is located at the Central Landfill in Petaluma, California.

During an extended demonstration period, the RNG plant successfully removed CO2, H2S, siloxanes, and VOCs to produce a natural gas equivalent, which was then compressed into CNG. The CNG was successfully used to fuel a transit bus, a pickup truck, and a passenger vehicle. While a small project, it is of interest because RNG was directly used to fuel vehicles, rather than to fuel vehicles by “proxy” through pipeline natural gas.

SCS has a patent on the technology employed at this Sonoma pilot program. The inlet capacity of the RNG plant was 100 scfm. The RNG plant incorporated the following technologies:

  • Vacuum/booster blower;
  • LFG refrigeration;
  • LFG compression;
  • Adsorption for H2S and VOC removal;
  • Membrane for CO2 removal;
  • Compression to produce CNG; and
  • CNG dispensing equipment.

SCS completed a feasibility study to select the preferred process chain for the RNG plant. SCS then designed and constructed the RNG plant on a turnkey basis. SCS was also responsible for securing the air permits for the project. The RNG plant was operated by SCS during a demonstration period extending from July 2008 through February 2010.