How GHGSat Proved Satellite Methane Measurement Accuracy in a Blind Controlled Release with TotalEnergies

Any emissions monitoring technology can produce data. The harder question is whether that data holds up when tested under conditions designed to remove any possibility of prior knowledge.

Blind controlled releases are the industry standard for validating the performance of emissions measurement instruments. The precise location and magnitude of the release are determined and controlled by an independent party. The technology being tested gets no advance information. Either it finds the emission and measures it accurately, or it does not.

In October 2020, less than two weeks after launch, GHGSat’s first commercial satellite was put to exactly that test—in partnership with TotalEnergies at their Lacq facility in France.

What happened

TotalEnergies controlled the release. Their personnel on the ground timed it to coincide with the satellite pass overhead, within a pre-agreed 12km x 12km field of view. GHGSat had no information about the precise location or release rate.

The satellite identified the exact location of the methane release. The satellite’s estimated emission rate of 250 kg/hr came within close range of the ground truth release rate of 234 kg/hr—independently confirmed by TotalEnergies.

At the time, it was the smallest methane emission ever detected from space.

Why this matters for emissions monitoring programs

Satellite data is only as useful as the confidence you can place in it. For operators running LDAR programs, for government agencies building national inventories, and for financial institutions assessing emissions risk across portfolios, the underlying question is always the same: can you trust the measurement?

This test answered that question directly. It showed that satellite methane measurement can locate an unannounced emission source within a large search area and quantify it with accuracy comparable to ground-based methods at a fraction of the cost and without deploying a single person to the field.

Ground-based LDAR technologies remain essential for low-threshold detection work. But they are limited in frequency and spatial coverage. Satellites provide the most cost-effective way to identify the largest emitters fast. Those super-emitter events account for over 60% of the total methane volume emitted by oil and gas facilities in the United States. Finding them quickly is where satellite monitoring earns its place in a tiered emissions program.

What came next

The validation opened the door to more advanced sensing applications. In June 2021, GHGSat and TotalEnergies announced a follow-on research project named Glint Mode—a world-first effort to demonstrate high-resolution satellite methane monitoring of offshore oil and gas platforms. Six TotalEnergies offshore facilities at locations around the world were observed as part of the 12-month program.

The two companies have worked together on greenhouse gas measurement and emissions reduction since 2018.

Want to hear more about how satellite monitoring is changing oil and gas emissions intelligence?

Listen to the GHGCast podcast episode: Keeping an Eye on Oil & Gas.