As the energy industry becomes more focused on reducing emissions, interest in methane emissions inventories for oil and gas is growing. You might have come across the term “emissions inventory” a few times, or your company may be exploring ways to calculate the most accurate inventory possible. Either way, we’ve got you covered: in this article, we'll explore what you need to know about emissions inventories, discussing their definition, their application and creation, and the significance of measurement-based inventories.
Now let’s get started with the basics.
A methane emissions inventory is a method for emissions reporting that consists of an estimate of the total mass of methane emitted–typically in kilograms or tons, over a period of time–often one year (annualized). For the oil and gas industry, an emissions inventory is determined for a specific geographic area, ranging in size from a single facility, all of an operator’s infrastructure, a basin, or even an entire country. The emissions inventory for a country would be called a “national emissions inventory.“
Methane emissions inventories are used for effective environmental management and to track emissions reduction progress. Some examples include:
Historically, emissions inventories relied heavily on emission factor-based estimates. But because emissions factors are quantitative estimates that represent the average emissions produced per unit of activity or fuel consumed, emissions factor-based inventories often don’t reflect reality. These discrepancies between estimated emissions and actual emissions have prompted methane experts across academia, industry, and government to advocate for the next generation of emission inventories: measurement-informed inventories.
Measurement-informed inventories are inventories based not on estimates, but rather on accurate measurements in the field. Measurement is invaluable to quantify larger emissions, anomalous emissions, and other types of sources that are typically undercounted using the traditional factor-based approach.
At Bridger Photonics, we see measurement-informed inventories as one of the next major frontiers for understanding and ultimately reducing emissions. Since you can’t manage what you can’t measure, accurate measurement that instills confidence is a critical first step to tracking and reducing emissions.
So, how can you leverage measurement to improve your emissions inventory? The first step is to select a measurement strategy which comprises two essential components:
In an ideal world, we’d measure everything, everywhere, and all the time to get a perfect understanding of emissions. But with limited budgets, time constraints, and many competing priorities this isn’t possible. So, we recommend taking an approach to assess where the bulk of your emissions originate, and focusing your measurement budget on those high-impact sources. This focused assessment is a statistically-based representative plan that incorporates the number of assets you have, the type of assets, and generates a plan that confidently calculates an emissions inventory. At Bridger, we’ve developed a process we call Sample Planning to enable prioritization so that you can get the most accurate measurement results with the resources you have available.
The next step after you select what you will measure, is determining the how. We recommend using a measurement technique that has at least equipment-level spatial resolution, the detection sensitivity to see the vast majority of your emissions (meaning large emissions as well as small emissions), and well-defined systematic error and uncertainties. Combined, these characteristics generate the clearest understanding of what is driving your emissions, how much you’re emitting, and the level of confidence you have in those results.
At Bridger Photonics, we’re approaching emissions inventories with scientific rigor that can help operators feel at ease. With our reliable aerial scans, year-round operations, minimal down days, and best-in-class emission source attribution to within 2 meters (~6 feet) or less, incorporating measurement into methane emissions inventories has never been easier or more accurate. We’re providing operators with actionable and source-level data to help build accurate, measurement-based inventories.
Rigorously backed by peer-reviewed scientific literature and trusted by top operators, we offer the most accurate measurement-based technology available to inventory your emissions and track your progress.
Fill out the form below and one of our team members will reach out to discuss your goals and how we can help you craft a measurement-informed emissions inventory.