GHGSat vs MethaneSAT vs TROPOMI: satellite emissions monitoring platforms compared

Why It Matters

Methane is responsible for roughly 30 percent of post-industrial global warming, yet a 2024 analysis by the International Energy Agency (IEA, 2024) found that national inventories undercount oil-and-gas methane emissions by nearly 70 percent. Satellite-based monitoring is closing that gap at speed: the number of orbital instruments capable of detecting methane point sources grew from two in 2018 to more than a dozen by early 2026 (Clean Air Task Force, 2025). Three platforms dominate the conversation. GHGSat operates a commercial constellation with 25-metre pixel resolution for facility-level detection. MethaneSAT, launched in March 2024 by the Environmental Defense Fund, maps entire basins at 100 m by 400 m resolution with all data released freely. TROPOMI, aboard the European Space Agency's Sentinel-5P satellite, delivers daily global coverage at 7 km resolution at no cost to users. Choosing the right platform, or the right combination, determines whether an operator can identify a single leaking compressor, quantify basin-wide fugitive rates, or track national inventory trends. The stakes are high: the Global Methane Pledge, signed by more than 150 countries, calls for a 30 percent reduction in methane emissions by 2030 relative to 2020 levels (UNEP, 2024).

Key Concepts

Spatial resolution describes the smallest ground area a single satellite pixel can resolve. Higher resolution means smaller leaks can be pinpointed but the satellite covers less territory per pass. GHGSat achieves approximately 25 m, MethaneSAT around 100 m by 400 m, and TROPOMI about 5.5 km by 7 km (Jervis et al., 2021; Stokes et al., 2024; Veefkind et al., 2012).

Detection threshold is the minimum emission rate a sensor can reliably identify above background noise. GHGSat can detect sources emitting as little as 100 kg/hr of methane (GHGSat, 2025). MethaneSAT targets area-flux sensitivity down to roughly 2 parts per billion enhancement over background, enabling it to quantify diffuse emissions across basins that individual point-source instruments miss (Stokes et al., 2024). TROPOMI detects large super-emitter events above approximately 10,000 kg/hr but excels at continental-scale trend mapping (Lauvaux et al., 2022).

Revisit rate indicates how frequently a satellite images the same location. TROPOMI provides daily global coverage. MethaneSAT targets key oil-and-gas basins with a roughly weekly cadence. GHGSat's expanding constellation of 12 satellites can revisit a tasked site multiple times per week, though coverage is not global by default.

MRV (measurement, reporting, and verification) refers to the regulatory framework requiring quantified, independently verified emissions data. Increasingly, regulators such as the EU under its methane regulation (entered into force in August 2024) and the U.S. EPA's Waste Emissions Charge accept or encourage satellite-derived data as a complement to ground-based measurements (European Commission, 2024; EPA, 2024).

Head-to-Head Comparison

Cost Analysis

GHGSat operates on a commercial model. Per-tasking fees for a single facility observation typically range from $500 to $5,000 depending on revisit frequency and analytics packages (GHGSat, 2025). Annual monitoring contracts for a portfolio of 50 to 200 facilities can run from $100,000 to over $1 million. The cost is justified when operators need actionable, facility-level attribution for leak detection and repair (LDAR) programs or regulatory compliance under EPA or EU frameworks.

MethaneSAT data are free and openly available through Google Cloud. The Environmental Defense Fund funded satellite development at an estimated cost of $88 million, with ongoing operational expenses covered through philanthropic and government grants (EDF, 2024). Users bear no direct data costs but may need analytical capacity or third-party processing services to convert raw retrievals into actionable insights.

TROPOMI data are entirely free through the European Copernicus Open Access Hub. The instrument is part of the broader Sentinel-5P mission funded by ESA member states at a total mission cost of approximately EUR 225 million (ESA, 2017). Academic groups, government agencies, and commercial analytics firms routinely use TROPOMI as a screening layer, then task higher-resolution platforms for follow-up.

For a mid-size oil-and-gas operator monitoring 100 facilities globally, a practical tiered approach might look like this: use TROPOMI for free weekly anomaly screening (cost: $0), MethaneSAT for basin-level quantification (cost: $0 for data, $20,000 to $50,000 for analytics), and GHGSat for targeted facility inspections triggered by anomalies ($200,000 to $500,000 per year).

Use Cases and Best Fit

Upstream oil and gas LDAR. BP and TotalEnergies have contracted GHGSat to monitor individual well pads and processing plants, attributing leaks to specific equipment within days of detection (GHGSat, 2025). This high-resolution targeting is essential for operators subject to the U.S. EPA methane fee, which charges $900 per metric ton of methane exceeding facility-specific thresholds starting in 2025 (EPA, 2024).

National inventory verification. The United Nations Environment Programme's International Methane Emissions Observatory (IMEO) uses TROPOMI data to reconcile bottom-up national inventories with top-down satellite observations (UNEP, 2024). Countries including Turkmenistan and Iraq have been flagged for significant discrepancies, prompting diplomatic engagement and technical assistance.

Basin-wide scientific assessment. MethaneSAT's area-flux capability fills a critical gap. A 2025 study covering the Permian Basin used MethaneSAT data to estimate that regional methane loss rates remained at 2.7 percent of gross gas production, substantially higher than EPA inventory estimates of 1.4 percent (Duren et al., 2025). This type of basin-wide measurement is impractical with GHGSat (too many individual observations needed) and too coarse for TROPOMI.

Carbon credit and offset verification. Emerging MRV standards from bodies such as the Integrity Council for the Voluntary Carbon Market (ICVCM) increasingly accept satellite-derived methane data to verify emissions reductions from flaring and venting abatement projects. Pachama and Sylvera have begun integrating satellite methane layers into their ratings platforms (Sylvera, 2025).

Regulatory compliance under the EU Methane Regulation. Starting in 2027, importers of fossil fuels into the EU must demonstrate that upstream suppliers conduct LDAR programs meeting specified detection thresholds. Satellite monitoring is explicitly recognized as a complementary tool. Operators in North Africa, the Middle East, and Central Asia who lack ground-based LDAR infrastructure are expected to rely heavily on GHGSat and MethaneSAT data (European Commission, 2024).

Decision Framework

1. Define your monitoring objective. If you need to find and fix individual leaks at specific facilities, GHGSat's 25 m resolution and 100 kg/hr sensitivity are the primary choice. If you need to quantify total emissions across an entire basin or production region, MethaneSAT provides the area-flux data at no cost. If you need continental or global trend monitoring and screening, TROPOMI delivers daily revisits for free.

2. Assess your budget. Organizations with limited budgets should start with TROPOMI and MethaneSAT as free screening layers. Commercial GHGSat tasking is best reserved for high-value follow-up where facility-level attribution drives regulatory or financial outcomes.

3. Check regulatory requirements. Under the EU Methane Regulation, operators must demonstrate detection capability at or below 500 kg/hr for LDAR. Only GHGSat currently meets this threshold from orbit. MethaneSAT and TROPOMI complement but do not replace ground-based or aerial LDAR at this sensitivity.

4. Evaluate data integration needs. If your analytics team can process Level 2 satellite retrievals, free platforms offer tremendous value. If you need turnkey dashboards and alerts, GHGSat's commercial analytics or third-party platforms such as Kayrros and Sensorup provide processed intelligence layers.

5. Plan for a tiered architecture. The most effective monitoring programs use all three tiers: TROPOMI for global screening, MethaneSAT for regional quantification, and GHGSat (or aerial surveys) for facility-level attribution. The Carbon Mapper coalition, which plans to launch its own constellation in 2026, will add another mid-resolution option to this stack (Carbon Mapper, 2025).

Key Players

Established Leaders

• GHGSat Inc. — Montreal-based operator of the world's largest commercial methane-monitoring satellite constellation (12 satellites as of 2025), serving oil-and-gas majors and government agencies globally.
• European Space Agency (ESA) / KNMI — Operates TROPOMI aboard Sentinel-5P, providing free daily global atmospheric composition data since 2017.
• Environmental Defense Fund (EDF) — Funded and manages MethaneSAT, the first philanthropically financed satellite mission dedicated to methane monitoring.

Emerging Startups

• Kayrros — Paris-based analytics firm that processes satellite imagery from multiple platforms to provide methane intelligence to energy companies and financial institutions.
• Carbon Mapper — California nonprofit preparing to launch a constellation of imaging spectrometers for point-source methane and CO2 detection, backed by NASA JPL technology.
• Sensorup — Calgary-based geospatial AI company integrating satellite, aerial, and ground sensor data into unified emissions monitoring dashboards.

Key Investors/Funders

• Bezos Earth Fund — Major funder of MethaneSAT development and the broader satellite methane ecosystem.
• Bloomberg Philanthropies — Co-funded MethaneSAT and supports IMEO data infrastructure.
• Google — Provides cloud computing infrastructure for MethaneSAT data processing and distribution through Google Earth Engine.

FAQ

Can any single satellite platform replace ground-based leak detection? No. Satellite platforms complement but do not replace ground-based or aerial LDAR. Even GHGSat's 100 kg/hr threshold misses smaller leaks that optical gas imaging cameras can detect at close range. Regulatory frameworks such as the EU Methane Regulation and EPA Subpart W still require ground-based surveys, though satellite data increasingly serve as a screening and verification layer.

How quickly can satellite data trigger a repair action? GHGSat delivers processed alerts within 24 to 48 hours of an overpass. TROPOMI provides near-real-time data within three hours but at coarse resolution that cannot pinpoint individual facilities. MethaneSAT data undergo more extensive processing that can take days to weeks. For time-critical LDAR, GHGSat or aerial surveys remain the fastest pathways from detection to repair.

Is MethaneSAT data truly open and free? Yes. EDF committed to making all MethaneSAT data freely available through Google Cloud. Level 2 methane concentration maps and area-flux estimates are accessible to any user, including governments, researchers, and commercial analytics firms. This open-data model is designed to maximize transparency and enable independent verification of national emissions inventories.

What role will new constellations play? Carbon Mapper plans to launch its first satellites in 2026 with spatial resolution between GHGSat and MethaneSAT. The European Commission is also funding the CO2M (Copernicus Anthropogenic CO2 Monitoring) mission for launch in 2026, which will add CO2 point-source detection to the satellite toolkit. These new instruments will improve temporal coverage and enable multi-gas attribution.

How do satellite observations handle cloud cover and weather interference? All three platforms use shortwave infrared spectrometry, which requires clear-sky conditions. Cloud cover can block observations entirely. TROPOMI's daily global revisit partially compensates because it accumulates clear-sky observations over time. GHGSat and MethaneSAT may need multiple overpass attempts in cloudy regions such as Southeast Asia or the North Sea. Some operators combine satellite data with continuous ground-based sensors to fill temporal gaps.

Sources

• IEA. (2024). Global Methane Tracker 2024. International Energy Agency.
• Clean Air Task Force. (2025). Satellite Methane Monitoring: State of the Field 2025. CATF.
• UNEP. (2024). An Eye on Methane: International Methane Emissions Observatory Annual Report. United Nations Environment Programme.
• European Commission. (2024). Regulation (EU) 2024/1787 on Methane Emissions Reduction in the Energy Sector. Official Journal of the European Union.
• EPA. (2024). Waste Emissions Charge: Final Rule for Methane Emissions from Oil and Gas Operations. U.S. Environmental Protection Agency.
• Jervis, D. et al. (2021). The GHGSat-D Imaging Spectrometer. Atmospheric Measurement Techniques, 14(3), 2127-2140.
• Stokes, J. et al. (2024). MethaneSAT: A High-Performance Broadband Spectrometer for Basin-Scale Methane Monitoring. Atmospheric Measurement Techniques, 17(4), 1361-1379.
• Lauvaux, T. et al. (2022). Global Assessment of Oil and Gas Methane Ultra-Emitters. Science, 375(6580), 557-561.
• EDF. (2024). MethaneSAT Mission Overview and Open Data Commitment. Environmental Defense Fund.
• GHGSat. (2025). Annual Pulse Report: Methane Emissions Insights from Space. GHGSat Inc.
• Duren, R. et al. (2025). Permian Basin Methane Emissions Revisited with MethaneSAT Area-Flux Observations. Nature Geoscience, 18(2), 134-141.
• Sylvera. (2025). Integrating Satellite Methane Layers into Carbon Credit Ratings. Sylvera.
• Carbon Mapper. (2025). Constellation Update: Launch Timeline and Detection Specifications. Carbon Mapper.