AB 2100 directs the State Air Resources Board to adopt regulations to reduce methane from dairy and livestock manure management in line with California’s SLCP strategy and to prepare the stakeholder and analytical groundwork before issuing those rules. It also requires the Department of Food and Agriculture to convene an interagency task force to evaluate alternative manure management practices and coordinate modeling, data sharing, and equity considerations.
The bill ties regulatory authority to feasibility: regulators must examine technical, economic, and market barriers and coordinate with energy agencies to enable biomethane projects, including pilot interconnection projects and financial mechanisms to lower environmental-credit risk. It preserves incentive pathways for enteric emissions and guarantees crediting for earlier projects while leaving monitoring and other emissions authorities intact.
At a Glance
What It Does
Requires the state board to adopt methane-reduction regulations for dairy and livestock manure management, contingent on findings of technological and economic feasibility; mandates pre-regulatory stakeholder processes and research; and creates a CDFA-led interagency task force to evaluate alternative practices and model adoption scenarios. It also directs energy agencies and the Public Utilities Commission to support biomethane infrastructure and pilots and sets rules for crediting and incentives.
Who It Affects
Dairy and livestock operations of all sizes (particularly those pursuing manure-to-energy projects), project developers, gas utilities and pipeline operators, waste and compost businesses, and state agencies including CARB, CDFA, CPUC, and the Energy Commission.
Why It Matters
The bill aligns manure-management policy with climate, water, and working-lands objectives and ties a potential regulatory backstop to concrete feasibility tests and energy-infrastructure actions, which will materially affect project economics, permitting, and market access for biomethane and compost products.
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What This Bill Actually Does
AB 2100 sets a clear policy architecture: it charges the State Air Resources Board (CARB) with adopting methane-reduction regulations targeting manure management in the dairy and livestock sectors, and it requires CARB to do preparatory work with affected parties before moving forward. CARB’s preparatory obligations include convening a broad stakeholder group, hosting at least three public meetings across regions with dairy and livestock operations, conducting or considering targeted research on manure-management systems (for example, scrape systems and solids separators), and weighing the development of methane-reduction quantification protocols.
CARB must post progress publicly and notify the Legislature about that progress.
The bill makes the timing of regulations conditional. CARB may implement its regulations on or after January 1, 2024 if, in consultation with CDFA, it determines the rules are technologically and economically feasible, cost-effective, and include measures to minimize leakage outside California.
The economic feasibility analysis must consider commodity prices (milk and cattle), available public and private funding, market demand for outputs (compost, biomethane), the ability to interconnect onsite generation to the grid, and access to pipeline injection points for digester gas. CARB is also required to evaluate how incentive programs have performed before relying on regulations alone.To shore up the market and infrastructure side, AB 2100 directs CARB, the Public Utilities Commission (CPUC), and the Energy Commission to develop policies and pilots that support dairy biomethane.
CARB must design a pilot financial mechanism to reduce the value uncertainty of environmental credits and provide recommendations to the Legislature on scaling it. The CPUC must direct gas corporations to run at least five dairy biomethane pilot projects that demonstrate pipeline interconnection; gas utilities may recover reasonable pipeline infrastructure costs from ratepayers for those pilot projects.
The bill also instructs CARB to provide guidance on how Low-Carbon Fuel Standard (LCFS) credits and other market-based compliance instruments apply to methane-reduction projects and to guarantee at least a 10-year crediting window for projects developed before CARB’s regulations take effect.Operationally, CDFA must convene an interagency task force composed of CARB, the State Water Resources Control Board, CalRecycle, the Natural Resources Agency, external scientific and technical experts, and producer representatives (including organic and pasture-based operators). The task force’s remit is to run scenario modeling for alternative manure practices under different policy and funding scenarios, assess interactions with groundwater and water-quality planning and working-lands climate goals, facilitate interagency data sharing, identify research gaps, and advise CARB on updates to the Alternative Manure Management Program’s quantification methodology with equity considerations in mind.
Finally, AB 2100 preserves CARB’s authority to require monitoring and reporting and clarifies that it does not displace air districts’ authority over criteria pollutants or toxic air contaminants.
The Five Things You Need to Know
The bill conditions the adoption of manure methane regulations on a set of feasibility tests (technological feasibility, economic feasibility considering milk and cattle prices and available funding, cost-effectiveness, and measures to limit leakage).
CARB must hold at least three public meetings in geographically diverse locations and convene a stakeholder group that includes project developers, dairy and livestock representatives, permitting agencies, compost producers, energy agencies, and public health experts.
CPU C must direct gas corporations to run no fewer than five dairy biomethane pilot projects demonstrating pipeline interconnection; utilities may recover reasonable pipeline infrastructure costs in rates for those pilots.
CARB must ensure projects developed before the regulations receive credit for at least 10 years under LCFS and related market-based compliance mechanisms, with the possibility of extension under later regulations.
Enteric emissions reductions remain incentive-only until CARB (with CDFA) determines a cost-effective, scientifically proven method exists that does not harm animal health, productivity, public health, or consumer acceptance.
Section-by-Section Breakdown
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Mandate to adopt manure methane regulations aligned with SLCP strategy
This provision tasks CARB with creating regulations to reduce methane from dairy and livestock manure management consistent with the state's short-lived climate pollutant strategy. Practically, that gives CARB a formal responsibility to produce enforceable rules that tie into California’s broader climate targets; it also sets the legal hook for later feasibility and stakeholder obligations elsewhere in the bill.
Pre-adoption stakeholder process, public meetings, research, and reporting
Before finalizing regulations, CARB must work with a broad stakeholder group to identify technical, market, regulatory, and other barriers to dairy methane projects, hold at least three geographically diverse public meetings, and consider or conduct research on specific manure-management approaches and potential methane-reduction protocols. CARB must publish a progress report online and notify the Legislature under Government Code Section 9795—an accountability step that forces transparency about the state of feasibility assessments and stakeholder input.
Interagency task force convened by CDFA to evaluate alternative manure practices
CDFA must lead an interagency task force that includes CARB, the State Water Resources Control Board, CalRecycle, the Natural Resources Agency, technical experts, and producer representatives (including organic and pasture-based operations). The task force must run scenario modeling for adoption of alternative practices, assess water-quality and working-lands interactions, facilitate data sharing, identify research needs, and advise on updating quantification methods for incentive programs—functions designed to harmonize climate, water, and agricultural policy across agencies.
Energy infrastructure, procurement policy, credit-risk pilot, and pipeline interconnection pilots
The bill requires CARB, in consultation with the CPUC and Energy Commission, to establish energy infrastructure and procurement policies and to develop a pilot financial mechanism that lowers uncertainty around environmental-credit values. CPUC must direct gas utilities to run at least five pipeline interconnection pilot projects for dairy biomethane, and utilities may recover reasonable pipeline costs in rates for those pilots—an explicit mechanism to test and underwrite grid and pipeline access for digester gas.
Credit guidance, transition protections, and enteric emissions rules
CARB must issue guidance on LCFS and market-based compliance credits for methane-reduction projects and guarantee that projects developed prior to CARB’s regulations receive at least 10 years of crediting. Enteric emissions reductions are constrained to incentive-based approaches until CARB and CDFA find a proven, cost-effective, animal-safe method—ensuring voluntary measures remain the default for enteric sources.
Limits and preserved authorities
The bill restricts CARB from enacting methane-control regulations for dairies and livestock to meet 2020 and 2030 greenhouse gas targets except as provided in the section, but it preserves CARB’s authority to require monitoring/reporting and does not affect air districts’ authority over criteria pollutants or toxics. This creates a narrowly tailored regulatory pathway while leaving other pollution authorities intact.
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Explore Environment in Codify Search →Who Benefits and Who Bears the Cost
Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- Project developers and technology providers — The bill backs infrastructure pilots, clarifies crediting rules, and funds a pilot mechanism to reduce credit-value risk, which lowers market and financing barriers for feedstock-to-energy projects.
- Pipeline and utility operators — CPUC-directed pilot projects and explicit permission to recover reasonable pipeline infrastructure costs create a near-term pathway for utilities to participate in digester-to-pipeline projects.
- Prior-project developers and early adopters — CARB must guarantee at least 10 years of crediting for projects that started before regulation, protecting revenue streams that underpin financing.
- Small and alternative-structure producers (organic, pasture-based) — The interagency task force explicitly includes representation for diverse production systems and must advise on equitable access and quantification methodology, increasing the chance these operations are considered in policy design.
Who Bears the Cost
- Dairy and livestock operators facing compliance or retrofit costs — If regulations move forward, operators may need to install new manure-management systems or adopt alternative practices, with costs that vary by operation size and system type.
- Ratepayers — Allowing gas corporations to recover reasonable pipeline infrastructure costs for pilot projects means utility customers could shoulder some of the upfront expense of interconnection demonstrations.
- State agencies and taxpayers — Convening the interagency task force, conducting modeling and research, and administering pilots will require staff time and funding; if not funded separately, these activities will compete with other agency priorities.
- Smaller operators without access to capital or markets — Even with equity language, small or remote producers may struggle to access funding, pipeline injection points, or long-term offtake contracts needed to make projects economical.
Key Issues
The Core Tension
The central dilemma is whether to rely on a cautious, feasibility-tied approach that reduces short-term economic harm to producers and markets or to impose firm regulatory mandates that drive faster methane reductions but impose concentrated costs on many farms; AB 2100 tries to thread that needle by coupling incentives, pilots, and a conditional regulatory backstop, but the balance depends on contested judgments about feasibility, fairness, and who ultimately pays for infrastructure and transitions.
AB 2100 binds the timing and scope of CARB’s regulatory authority to a set of feasibility findings, which is pragmatic but creates ambiguity. Economic feasibility hinges on volatile inputs—milk and cattle prices, availability of state and federal dollars, private capital, and market demand for compost and biomethane—meaning the regulatory backstop could be significantly delayed if markets shift unfavorably.
That conditionality protects producers from one-size-fits-all mandates but risks undercutting the predictability climate-focused investors need to finance larger transformations.
The bill also centralizes coordination among several agencies and creates a task force with broad mandates (scenario modeling, water-quality alignment, quantification-methodology updates). Those are essential analytic tasks, but they require sustained funding, data-sharing agreements, and methodological choices that can materially change project eligibility and crediting.
The provision allowing utilities to recover pipeline costs for pilots lowers a practical barrier to interconnection but socializes early infrastructure risk; absent tight guardrails, ratepayers may pay for demonstrations that do not scale or that primarily benefit larger producers. Finally, the guarantee of at least 10 years of crediting for pre-rule projects stabilizes early investment but could create market distortions if new rules later shift baselines or eligibility criteria.
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