By Conner Adams, Client Advisor, Asset Development, EcoEngineers

As the voluntary carbon market (VCM) evolves to meet higher standards of integrity and transparency, landfill gas destruction remains a proven and widely supported method for reducing greenhouse gas (GHG) emissions. VCM landfill gas destruction projects collect and destroy methane, a super pollutant, from landfill gas emissions via combustion to create methane emission avoidance credits. Though not without their controversy,^[1] all major methodologies for landfill gas destruction have received the Core Carbon Principle (CCP®)-approved label by the Integrity Council for the Voluntary Carbon Markets (ICVCM).

As a result of achieving the CCP®-label, the transaction volume of methane emission avoidance credits increased by 2.5 times in 2024 over the previous year, and in recent years, per credit prices for this category have risen significantly compared to nominal lows of approximately US$1.90 per metric ton ($/MT) from the prior decade to spot prices up to $8.30/metric ton in July 2024, as reported by the Climate Action Reserve (CAR). More recently, prices have cooled to a quasi-steady value of approximately $5/metric ton over the course of 2025, as reported by AlliedOffsets.

Two leading ICVCM carbon programs, CAR and ACR,^[2] alone hosted over 50 landfill gas destruction projects in the United States (U.S.) as of Q1 2025 with an estimated impact of greater than 2.5 million metric tons per year of methane emission avoidance credits on average in recent years.

Untapped Domestic Opportunities to Generate Methane Avoidance Credits

Analysis of the Landfill Methane Outreach Program (LMOP) dataset published as of September 2024 by the U.S. Environmental Protection Agency (USEPA) indicates that there are 444 candidate landfills in the U.S. Candidate landfills are those defined as having the potential to support a landfill gas energy use project based on the following criteria:

• Currently accepting waste or has been closed for five years or less,
• Has at least one million tons of waste, and
• Does not have an operational, under-construction, or planned landfill gas energy project.

Of the reported candidate landfills, roughly one-fourth (126 out of 444) have characteristics likely suitable for the development of a VCM project. These are landfills with the following reported characteristics that would meet CAR or ACR’s eligibility criteria:

• Do not have an active landfill gas collection and control system in place with or without passive flares and/or perimeter gas wells,
• Do not recirculate leachate,
• Are not permitted as research, development, and demonstration (RD&D) landfills and thus are not bioreactor landfills, and
• Are not located in California.

Theoretically, project developers could leverage a variety of accepted technologies at these sites to achieve methane destruction, including but not limited to combustion of landfill gas in a flare, use of landfill gas in an engine, boiler, or turbine to produce heat and/or power, or upgrade and use of the upgraded gas (also called renewable natural gas, or RNG) as compressed natural gas (CNG) or liquified natural gas (LNG) on or offsite of the project landfill.

In practice, a number of these landfills will eventually host an RNG project and participate in another mitigation crediting program such as state low-carbon fuel standard programs (LCFS) and/or the federal Renewable Fuel Standard (RFS). Projects participating in these other mitigation crediting programs may also participate in ICVCM carbon programs; however, these projects will be prohibited from generating methane avoidance credits where such claims stack with crediting periods of these other programs due to prohibitions on credit stacking.

Some of the landfills with suitable characteristics may be years away from generating economically sufficient flow volumes of landfill gas to facilitate an RNG project, or otherwise, and other sites still may never be deemed economically suitable for a beneficial use project. For these types of sites, participation in the VCM via the development of a methane destruction project may be highly suitable. Additional opportunities may exist outside of this analysis of USEPA candidate landfills, where sites do not otherwise meet the definition of a USEPA candidate landfill but possess suitable characteristics for a VCM project and do not presently host an RNG project.

Understanding Technological Barriers and Innovations

A key suitability check for a landfill gas project developer is accurately estimating the eligible gas flow to ensure financial viability. The offtake value of methane avoidance credits must sufficiently exceed the costs of installing and operating the destruction system, as well as maintaining collection and destruction systems and performing metering, monitoring, reporting, and verification (MMRV) activities to secure credit issuance.

Passive flares that exist at some sites, installed to control odors or otherwise, pose the greatest barrier to estimating eligible gas flows. Carbon programs require that any emissions destroyed by these pre-existing devices be deducted from quantified outcomes, meaning that only incremental additional destroyed gas flows collected and destroyed by the increased collection capacity installed by the project developer can be claimed for crediting purposes.

The typical method to quantify this deduction is to install and operate potentially high-cost metering technologies for at least three months, though not all passive flare types and configurations can feasibly support such integration. Alternatively, in some cases, project developers could deduct the maximum flow capacity for gas destruction that a passive flare could technically accommodate, where such information exists.

Project developers in recent years have built on these established methods to create new opportunities for landfill sites historically ineligible to participate in the VCM. For example, LoCI Controls Inc., a technology vendor and project developer headquartered in Wareham, Massachusetts, found a home for their automated collection and control system upgrade methodology with ACR and now has nearly a dozen projects accepted or in the pipeline for approval. This method allows for crediting incremental gas flows collected and destroyed at sites resulting from the voluntary implementation of new technologies that optimize wellfield tuning to capture more gas. However, this method relies upon information reported to the USEPA’s Greenhouse Gas Reporting Program (GHGRP) that is made publicly available in the Facility Level Information on Greenhouse Gases Tool (FLIGHT), which may cease to be a source for data in the coming years^[3] and thus prevent the rollout of new projects.

Recommendations

If you think that your landfill site meets these eligibility criteria, EcoEngineers recommends a thorough project-level study to confirm that your site is suitable for participation in an ICVCM carbon program.

Contact EcoEngineers to understand your landfill site’s overall suitability to host a VCM landfill gas destruction project. EcoEngineers has been a leader in supporting project developers in successfully registering their landfill gas destruction projects in recent years.

Our team of experts can help you:

• Navigate all requirements of CPP®-approved methodologies and carbon crediting programs for landfill gas destruction.
• Determine suitability and outline key risks and rewards of any potential site for a VCM project.
• Support the development of a Project Design Document (PDD) to ensure the project’s monitoring plan can produce monitoring reports that are compliant with all requirements to successfully pass validation/verification.
• Quickly develop emission-reduction estimates and reports for validation/verification using our in-house proprietary models.

About the Expert

Conner Adams is a Client Advisor at EcoEngineers.  He helps clients develop renewable energy, emissions reduction, and carbon dioxide removal projects for the VCM. Among other areas, he has specialized in supporting project developers assess, design, and model landfill gas destruction projects to deliver decarbonization benefits today.

For more information about EcoEngineers’ Asset Development services and capabilities, contact:

Conner Adams, Client Advisor, Asset Development | cadams@ecoengineers.us    

[1] In July 2024, CarbonPlan published the article, titled “The first offset credits approved by a major integrity program don’t make the grade.” In this article, they explored additionality concerns on a sample of older CAR landfill gas projects that resumed activity after a long period of reporting dormancy. Climate Action Reserve formally rebuked these claims in a September article titled “2024 STAYING IN CHECK: Presentation of facts to counter inaccuracies in CarbonPlan’s article, titled “The first offset credits approved by a major integrity program don’t make the grade.”

[2] Formerly the American Carbon Registry.

[3] On March 12, 2025, Administrator Lee Zeldin of the USEPA announced that agency will be reviewing of the scope of the Greenhouse Gas Reporting Program (GHGRP), which mandates reporting of GHG emissions data for over 8,000 industrial point source facilities including landfills.