Sampling systems are critical for accurate analysis of Renewable Natural Gas (RNG), but sampling and analysis requires subject matter expertise. RNG compositions vary widely by location and feedstock, according to sampling expert, Kenneth Thompson, CEO and President of Mustang Sampling and Valtronics Inc.
Thompson spoke at the recent Southeast RNG Conference in Charlotte and commented, “The analysis of RNG is different from natural gas.” “RNG begins as an unknown mixture of different components depending on the production processes and feedstock,” according to Thompson’s conference presentation. “The gas composition evolves throughout cleaning and upgrading, until it is nearly pure methane in the final state.”
Gas composition determines gas properties including the sample’s energy density, monetary value, RNG Integrity, and suitability for distribution. Understanding the composition of RNG is also critical for its safe use as an energy source.
Last June, the U.S. Environmental Protection Agency announced the Renewable Fuel Standard (RFS) Program, setting fuel standards for the next three years. Key changes to the regulations for RNG producers, according to Thompson, include:
- Only RNG producers can generate Renewable Identification Numbers (RINs), tradeable credits within the RFS program, for RNG injected into a natural gas commercial pipeline system;
- Measurement methods and procedures to determine the heating value of RNG are now defined;
- Volumes reported to EPA must be determined according to standards adopted by the American Society for Testing and Materials (ASTM).
Thompson told the conference audience the largest challenges to introducing RNG into natural gas distribution systems include:
- RNG’s maximum energy value is near the lower limit allowed by gas interchangeability rules,
- Standard alarm and blending requirements differ by location, and dilution may impact burner-tip performance,
- Existing gas tariffs do not address commonly found contaminants in RNG, like siloxanes or bio-contaminants,
- Establishing equitable rules between natural gas and RNG is challenging,
- Industry experience is extremely limited.
To learn more about Renewable Natural Gas Sampling and Analysis attend the 2024 Appalachian Conference on Thursday, April 18, 2024, at the Hilton Garden Inn Southpointe, Pennsylvania. The 2024 Conference will provide information from industry experts who are leading the growth of the RNG industry.