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Renewable Natural Gas in California


Beginning in June 2018, the TomKat Energy Impact Fellows investigated biogass emissions from dairy farms and landfills, and whether it can be used as Renewable Natural Gas (RNG) in the state of California. 

Over the past decade, California has undertaken aggressive steps to capture and utilize fugitive methane emissions from a variety of sources where they are an unavoidable byproduct. These include biogas emanating from landfills, wastewater treatment plants, farms, and dairies. To combat these climate pollutants, the California Senate Bill 1383 was signed into law in 2016 which established targets to achieve a 50% reduction in the level of statewide disposal of organic waste from the 2014 level by 2020 and a 75% reduction by 2025. In addition, SB 1383 requires that dairies in California control their methane emissions as early as 2024. The bill mandates the establishment of infrastructure and policies for dairy farms to reduce methane emissions by up to 40% from 2013 levels by 2030. The challenges and opportunities presented by these two initiatives are the primary focus of this study.

Various incentive schemes at the state and federal level have proven to be powerful driving forces behind biogas capture, conversion, and commercialization efforts. Chief among these is the Renewable Fuel Standard which requires, among other things, a traceable pathway from suppliers to end users in transportation vehicles. However, to date, California has trailed other states in the advancement and harnessing of biomethane and renewable natural gas (RNG) opportunities for a variety of reasons including:

  1. Sub-optimally aligned and coordinated regulatory/permitting processes and agencies
  2. Excessive project time and cost
  3. Economic and regulatory barriers to biogas utilization including significant regulatory hurdles for pipeline injection.

Resolution of these obstacles will be key to realizing the objectives of SB 1383.

It has been estimated that the Organics Diversion effort will require the establishment of 150-200 new “landfill equivalents” in California at a cost of $1.5-2.5B.

  • Given that only 2 new landfills have been approved in the past 2 years, it is clear that a dramatic re-design and streamlining of the approvals process will be required.
  • Upgrades to existing recycling facilities and some of the 900 wastewater treatment plants in California could absorb a large portion of these diverted organics and possibly reduce the regulatory burden and investment required.
  • A major challenge is the variable and sometimes excessively high (40%) contamination levels in organic waste. A much more aggressive statewide effort of outreach, education, and enforcement will be required to bring these levels down to an ideal 5-10%.
  • It is imperative that obstacles to pipeline injection and on-site electricity generation be conclusively addressed and resolved. From a resource management and financial perspective, it is undesirable that it is currently easier to flare biogas than it is to make use of it.

The challenges faced by dairies in California are primarily a function of their size and distributed nature. Their inability to individually realize economies of scale and their distance from potential offtake sites significantly erodes the economic viability of their biogas generation potential.

  • Concepts based on dairy cluster models with a variety of processing, transportation, local utilization, and pipeline injection options do appear to offer a pathway to project viability. These have been successfully piloted in other regions and the results of the scheduled PG&E cluster study should go a long way toward defining the operational and economic frameworks of this model.
  • It is imperative that governance of local zoning and land use ordinances be expedited on a case-by-case basis to facilitate these undertakings. Standards must be developed that address the interests of surrounding communities, yet, that do not create undue burdens on the already stressed dairy industry.

Through the TomKat Fellows' research, the team was able to provide recommendations to public policy, utilities, and private industry on actions and changes that can be made to promote sustainable growth in the production of biogas, as well as recommendations to fulfill waste diversion goals set by the California government. The full findings of the TomKat Fellows' research can be found in their final report.