Methane concentration only tells you how much methane is present in the air at a specific moment in time. Flux measurements quantify the actual rate of methane being emitted by the animal. GreenFeed measures methane flux directly by capturing and analyzing every breath under calibrated airflow conditions, providing accurate, repeatable, and publishable per-animal emissions data.
"How much methane is in the air right here, right now?"
Measures gas content of a sample of air, in ppm. A property of the air — sensitive to wind, ventilation, sensor position, and animal behavior.
"How much methane is the animal producing per day?"
Measures mass leaving the animal per unit time, in g CH₄/day. A property of the animal — attributable to a single ID on a single day.
02
A concentration reading depends on a dozen variables outside the animal — wind speed, sensor distance, head position, dilution, barn airflow, sampling duration, ambient conditions. The same animal can produce dramatically different concentration readings depending on which of those variables happens to be in play. Without accounting for airflow and time, concentration alone cannot determine the animal's actual methane emissions rate.
The same cow. The same daily emissions. Measured two days apart on the same pasture — one calm morning, one windy afternoon.
Without wind to disperse it, methane pools around the animal. A passive sniffer reads a large number.
Wind dilutes the plume almost immediately. The same sniffer now reads 11× lower.
The concentration changed by an order of magnitude. The cow's actual emissions never moved. That's the gap GreenFeed closes by measuring airflow at the point of capture — so the number you report reflects the animal, not the weather.
03
GreenFeed solves the variability problem at its source by measuring the actual airflow, background gases, and environmental conditions that sniffers ignore. The result is per-animal emissions data that's comparable across herds, regions, and time periods.
Every GreenFeed unit is manufactured and calibrated to a standard. Data from a dairy in Europe is directly comparable to a feedlot in North America. The same measurement, the same way, every time.
Identical hardware and calibration means identical methodology. The same study will yield the same results if done over.
Animals are measured during normal feeding behavior on pasture, in feedlots, or in dairy barns. No chambers, no restraint, no behavioral distortion of the data.
Captures every visit only when the animal's head is properly positioned in the hood, ensuring full breath capture. Invalid positions are flagged and excluded automatically.
A calibrated fan actively pulls 40 liters of air per second through the system, capturing all ambient air around the animal's head.
Wind speed, background gases, environmental conditions, head position — the same variables that ruin sniffer readings are measured, accounted for, and corrected for on every single visit.
03
Flux measurements combine methane concentration with airflow and time to quantify the actual methane emitted by the animal.
01
Every exhalation captured under controlled conditions.
02
CH₄ and CO₂ captured in animals controlled environment.
03
Calibrated capture rate of 40 L/sec.
04
Integrated across each visit, every animal.
05
Concentration × flow rate × time = mass.
The cleaner and more complete the methane data, the better the outcomes \u2014 for producers chasing profitability, for researchers chasing answers, and for corporations chasing defensible sustainability claims. Direct measurement is what makes all three possible.
For Producers
Cleaner emissions data gives producers a direct line into feed efficiency. Per-animal methane intensity and CO₂ output reveal which animals convert feed most effectively, which rations perform best, and where margin is being left on the table — turning emissions data into a profitability tool.
For Researchers
When every data point comes from the same standardized method, study results become comparable, reproducible, and defensible. Cleaner inputs mean stronger statistical power, fewer confounding variables, and the kind of evidence base that advances the science instead of just adding to it.
For Corporations
Sustainability reporting depends on numbers that hold up under scrutiny. Direct flux measurements give corporations actual measured emissions to report on — not modeled approximations — the kind of evidence that satisfies auditors, regulators, and downstream buyers.
GreenFeed directly measures methane flux to produce scientifically defensible per-animal emissions data trusted by researchers around the world.
GreenFeed methodology is cited in 800+ peer-reviewed publications. These four are the most-referenced for the topics covered here.
