Announcement Details

The Collaboratory to Advance Methane Science (CAMS) is seeking responses to a funding opportunity to reconcile top-down and bottom-up measurements of methane emissions from the production of oil and gas in the Permian basin. The work will help to improve our understanding of the persistent differences between top-down and bottom-up estimates in different producing regions and, in turn, build confidence in emission estimates from both approaches.

Responding entities should submit full proposals for projects by May 06, 2022. It is anticipated that one award will be made with funding ranging from $250,000- $350,000.

Primary Study Objectives

The primary objective of the funded work will be to assess the limitations of top-down and bottom-up estimation methods in quantifying regional methane emissions and develop a framework for incorporating top-down measurements to improve bottom-up estimates of methane emissions for production operations in the Permian basin. While the study will focus on the Permian basin and available data existing for the basin, the output should be applicable to other basins and other available data. The study should leverage the variety of existing methane emissions data sources and modeling tools that are available. Careful consideration needs to be taken of all variables influencing methane emissions, fully accounting for super-emitters and temporal variability of source emissions.

This research will allow CAMS to build on past successes and continue to advance the science around methane emissions. This will be accomplished by sponsoring and engaging in research targeted at identifying, understanding, and supporting the most viable technologies to ultimately reduce overall methane emissions.

Specific study objectives include to:

1. Augment bottom-up emission estimating methods using an existing spatial and temporally resolved model or assessment tool and available top-down measurement data;
2. Evaluate the assumptions generally applied to top-down measurements that can account for gaps between top-down and bottom-up estimates, including duration of measurements, instrument quantification accuracy and precision, intermittency of emissions, and disaggregation of emissions / spatial resolution;
3. Develop a template to assess the appropriateness of metrics for comparison of measurements across different regions and estimation techniques;
4. Explore opportunities for this work to complement or augment the evolving space of emission reporting frameworks and scientific measurements.

Provide a framework to improve emission inventory calculation methods, taking into account the importance of comparable intensity metrics and incorporating learnings from the objectives above.

The study objectives can be accomplished with an assembled team that can include academics, environmental organizations, technology vendors, or a collaborative effort between several entities.

The successful project should build on previous efforts to reconcile top-down and bottom-up methane emissions estimates in different regions of the United States, including the Fayetteville Shale (Vaughn et al. [2018], Zavala-Araiza et al. [2015]). In addition, the project should leverage available data sources including (but not limited to):

• Top-down data sources such as PermianMap, TROPOMI, NASA/JPL AVIRIS-NG, and other datasets emerging from a growing body of literature (e.g. Robertson et al. [2020]);
• Existing emissions estimation models such as the CAMS Methane Emissions Estimation Tool (“MEET”)¹ ;
• Commercially available, non-methane datasets (e.g. IHS, Enverus, or Rextag). These data sources can lend additional operational insights not found in standard bottom-up inventories like GHGRP, such as midstream operation locations and well completion and production data. These are key data points for operations such as well completions, compressor start-ups and blow-downs that can result in emissions that are high in magnitude but short in duration.

This should create a context to understand different results produced from bottom-up inventory calculations and top-down studies and evaluate mitigation strategies that could be effective in reducing total emissions. Lessons learned should be applicable to other regions and basins.

In addition, the research should aim to complement or augment voluntary emission reporting frameworks and scientific research in this space, to the extent appropriate and practicable. Given the emerging consensus on the limitations of emission factors, the quantification of site-specific emissions is an important factor that is of growing interest to operators, regulators and other industry stakeholders.

The results of this effort will benefit:

• Regulators and policymakers concerned with methane emissions
• Operators and environmental organizations seeking to understand the accuracy and limitations of their data; and
• Measurement technology vendors and emissions monitoring operators to identify sources of data inconsistencies.

Background

The O&G industry is committed to continuously studying and reducing environmental and climate impacts based on the most up to date scientific knowledge. Methane emissions from oil and natural gas activity are a significant contributor to greenhouse gas emissions, with the production segment as the leading contributor.

“Top-down” studies are performed on a regional scale using various remote sensing techniques such as satellite and aircraft to measure ambient methane concentrations, calculate methane flux based on atmospheric and meteorological conditions, and attribute the emission to different activities.²

“Bottom-up” estimations rely on direct measurements, engineering calculations, manufacturer data and emissions factors for emissions sources and activities, compiled based on a representative sample to develop an aggregated account of emissions from a producing region or asset.³

Previous research has shown that traditional inventory-based or bottom-up methods consistently report lower emissions compared with top-down assessments. Part of the explanation for bottom-up inaccuracies can be linked to an emergent class of emissions known as “super -emitters.” These high-emitting sources are not well represented in national inventories and represent the largest contributors to overall emissions; it is estimated that about 5% of sources contribute to 50% of overall emissions. These high-emitting sources can be attributed to process excursions such as an open thief hatch on a tank that fails to reseat, a flare that is unlit or operating with reduced combustion efficiency, or other issues.

Various groups publish “top-down” methane emissions measurement studies and syntheses of those studies, but there is no established framework by which to judge the accuracy and credibility of such studies. Top-down measurements also rely on a variety of assumptions and extrapolation methods that require further evaluation, particularly in the extrapolation and intertemporal comparisons.

We know from previous studies that emissions vary both temporally and spatially, and aggregated and annualized activity and emission factors can differ substantially from local emissions estimated based on a short survey of a relatively small sample. Without temporal and spatial reconciliation, bottom-up and top-down estimation methods will produce different accounts of emissions from a given area. There are a variety of reasons that top-down emissions studies do not compare well to bottom-up equipment and activity factor-based inventories. This study should provide a framework that outlines steps that should be taken in order to make meaningful comparisons of bottom-up and top-down emissions inventories.

Deliverables

• A report that provides a framework for determining the various assumptions, sensitivities, uncertainties and potential associated error for top-down measurements, including (and satellite and aerial assessments);
• Peer reviewed paper(s) describing the methodology and presenting the reconciliation. Paper(s) should include careful consideration of the appropriateness of metrics to compare different measurements and calculations to one another, and different regions to one another.
• A framework that outlines the underlying data and calculations needed to improve the accuracy of emissions intensity metrics that are used today, and that takes into consideration the comparability of resulting estimates and metrics, including recommendations for next steps.

RFP Release Date: 03/30/2022
Deadline to submit proposals: 05/06/2022
Submit proposals to: cams@gti.energy
Anticipated Award Date: 06/10/2022
Anticipated Project Start Date: 07/18/2022
Anticipated Period of Performance: 5 months

Available Funding: $250,000-$350,000, no matching funds are required

Questions on the funding opportunity should be directed to:

Keily Miller
CAMS Program Administrator
cams@gti.energy

Eligibility

The solicitation is open to public and private entities. The successful contracting group should consist of a team of experts with data analysis and statistical experience and field design and execution experience at oil and gas operations.

¹ MEET software is free to use and is hosted by UT Austin: http://dept.ceer.utexas.edu/ceer/meet/

² IOGP/IPIECA Methane Glossary - https://www.ipieca.org/resources/awareness-briefing/methane-emissions-glossary/

³ Ibid.