Clean Energy. Clean Energy has applied for three landfill-gas-to-biomethane fuel pathways. The landfill gas (LFG) for all three pathways is extracted from the Cedar Hills (CH) landfill in Maple Valley, Washington.

One pathway covers the liquefaction of the resulting biomethane at Clean Energy’s Boron, California liquefaction facility and dispensing of the fuel as liquefied natural gas; one pathway covers the liquefaction of the resulting biomethane at Clean Energy’s Boron, California liquefaction facility and then the vaporization and compression of the liquefied natural gas into compressed natural gas; and the final pathway covers, and the final pathway covers, the compression of the biomethane for dispensing at compressed natural gas (CNG) fueling stations. All stations covered in the pathways are located in California.

Clean Energy calculated the carbon intensities (CIs) of the LNG and CNG pathways to be 18.14 and 15.56 gCO₂e/MJ, respectively. These pathway CIs are somewhat higher than the existing California LFG-to-biomethane pathways. California LFG-based LNG has a CI of 15.56 gCO₂e/MJ, while CNG from California LFG comes in at 11.26 gCO₂e/MJ.

Element Markets. Element Markets Renewable Energy, LLC applied for a Low Carbon Fuel Standard (LCFS) pathway for the production of liquefied natural gas (LNG) from landfill gas (LFG) produced in Pennsylvania. Element Markets purchases the LFG from Johnstown Regional Energy LLC (JRE), an operator of LFG processing facilities at three Eastern Pennsylvania landfills: Raeger Mountain Landfill, Southern Alleghenies Landfill, and Shade Landfill.

All three landfills are owned and operated by Waste Management Inc. Together, the three facilities produce up to 2,500 million Btu/day (912,500 million Btu/year) of LFG. Elements Markets purchases the processed LFG and injects it into an interstate pipeline system operated by Dominion Transmission Inc. This system primarily collects natural gas from North American wells in the region. The gas Element Markets purchases is transported 3,000 miles by pipeline to California, where it is liquefied at an average liquefaction efficiency of 80%. This LNG fuel is used in LNG vehicles.

The CI of this pathway, as calculated by Element Markets, is 32.53 gCO₂e/MJ of LNG produced. This CI is based on energy consumption records from the LFG processing plant covering the last eight months of 2011 and all of 2012, and an average liquefaction efficiency of 80%. By comparison, the Lookup Table CI for California LFG liquefied in California is 26.31 gCO₂e/MJ. The Element Markets pathway CI is higher than the CI of LNG006 due to a lower LFG processing efficiency, a longer pipeline transmission distance, and a regional electricity generation mix characterized by higher GHG emissions.

San Diego Metro. San Diego Metropolitan Transit System (SDMTS) has applied for a landfill-gas-to-biomethane pathway. The feedstock landfill gas (LFG) for this pathway is extracted from the Cedar Hills (CH) landfill in Maple Valley, Washington, processed to pipeline quality, and injected into the interstate pipeline system. SDMTS extracts this biomethane from the pipeline and dispenses it in the form of CNG to power a portion of its transit fleet.

SDMTS calculated the CI of its LFG-to-CNG pathway to be 13.36 gCO₂e/MJ. As noted above, the CI of the existing LCFS pathway for the production of CNG from California LFG is 11.26gCO₂e/MJ. The CI of SDMTS’s CH pathway is higher than the CI of the corresponding California pathway for the following reasons:

• The CH plant consumes electricity generated from a Northwest energy mix (as defined in the US Environmental Protection Agency’s eGRID system). LFG processing plants operating in California consume California marginal electricity.

• Biomethane from the CH plant is transported 1,250 miles by pipeline to CNG stations in Southern California, while biomethane from California processing plants moves only 50 miles by pipeline.

• The efficiency of the compressors SDMTS uses to produce CNG is lower than the default efficiency used in the default pathway.