CR&R pathway for biogas from anaerobic digestion of green waste to CNG has LCFS CI of just above zero

December 6, 2018. California Renewable Power LLC (CR&R) has submitted a California LCFS Tier 2 application for its biomethane from anaerobic digestion of green waste to CNG pathway, with a requested carbon intensity (CI) of 0.34 gCO2e/MJ.

   The CR&R facility produces biomethane from an organic waste anaerobic digester (AD) facility in Perris, California that is co-located with CR&R’s material recovery facility and transfer station.

   The facility receives pre-separated green waste from households and commercial generators, and sends it to an anaerobic digestion unit to produce raw biogas. The raw biogas is cleaned up in an onsite upgrading facility where it is upgraded to Rule 301 pipeline quality biomethane.

   The upgraded biomethane is injected into the SoCalGas pipeline and this fuel is eventually compressed and dispensed as CNG. The facility also transports digestate and compost using heavy-duty CNG trucks.

   Although the input feedstock consists of limited food scraps (<5%), CR&R is seeking to register a provisional pathway of biomethane from anaerobic digestion of 100% green waste with this application.

   The CI value is based on life cycle analysis conducted using a modified version of the High Solids Anaerobic Digestion (HSAD) calculator under the CA-GREET 2.0 Tier 2 methodology as described in the Life Cycle Analysis (LCA) Report.

   ARB staff has reviewed the CR&R application and has replicated, using the modified version of the HSAD calculator, the CI value calculated by CR&R. On the basis of these findings, CARB staff recommends that the CR&R application for the LCFS pathway be provisionally certified, subject to specific operating conditions.