Renewable Natural Gas Flow Rate Estimation Tool
The Renewable Natural Gas (RNG) Flow Rate Estimation Tool (RNG Flow Tool) serves as a screening guide to help landfills quickly estimate normalized gas flows for RNG projects. The Tool calculates the adjusted flow rate and corresponding heat content (Btu) value of landfill gas (LFG) after adjusting a wellfield to meet the inlet specifications for RNG treatment/processing technology. Raw LFG has a lower Btu content relative to RNG, so LFG must be upgraded with certain treatment technologies to be successfully converted to RNG.
The RNG Flow Tool was developed to provide an approximate estimate of the potential impact on LFG flow rate, Btu content and quality following wellfield adjustment prior to LFG treatment for an LFG-to-RNG energy project. These treatment technologies often specify that the inlet gas quality must contain nitrogen levels lower than what may be typically measured in LFG – adjusting the LFG collection system to achieve these nitrogen targets may impact the LFG flow rate. The type of RNG delivery method and the associated gas quality specifications for that delivery method or ultimate end use also affect what inlet nitrogen levels are allowable.
Landfill-specific data for LFG flow rate and composition should be used in the Tool if available, but the Tool provides default gas constituent assumptions for nitrogen, methane, carbon dioxide and oxygen from raw collected LFG.
Download the RNG Flow Rate Estimation Tool (January 2020) (xlsx)