NET Alcohol Estimator
CO2 Gas Flow Sensor — Estimate Alcohol Production in Real Time
Measure Alcohol Production During Fermentation
The NET Alcohol Estimator measures CO2 gas released during fermentation to estimate alcohol production. The GOvent NET replaces a standard vent valve with one featuring internal gas flow sensing.
The system continuously tracks gas volume measurements compensated for temperature, pressure, and humidity, and transmits data to the controller display. View estimated ethanol production and concentration via the free mobile app (iOS/Android).
Real-Time Fermentation Monitoring
CO2 Gas Flow Sensing
Internal gas flow sensor measures CO2 released during fermentation. Volume measurements are automatically compensated for temperature, pressure, and humidity for accurate readings.
Mobile App Integration
View estimated ethanol production and concentration in real time via the free mobile app for iOS and Android. Monitor fermentation progress from anywhere.
Automatic Gas Release
Gas release is actuated automatically by the GOfermentor controller. Also includes overpressure safety release function for protection during fermentation.
Controller Display
Data is transmitted to the GOfermentor controller display for local monitoring. Track ethanol estimates without needing your phone.
Easy Replacement
The GOvent NET simply replaces the standard vent valve with a 2" Triclamp connection. Compatible with new GOfermentor NET units or retrofit-able to pre-2022 models.
Compensated Measurements
Gas volume measurements are automatically compensated for temperature, pressure, and humidity — providing reliable estimates regardless of ambient conditions.
How Ethanol Estimation Works
Knowing the alcohol concentration during fermentation is essential for winemakers. In addition to determining when the sugar is depleted, knowing the rate of ethanol production can provide insight into whether the fermentation is "stuck", complete, or progressing normally.
Once fermentation is underway, the evolved gas is almost entirely CO2 with some water vapor and evaporating ethanol. The stoichiometric relationship between CO2 evolved and ethanol produced means that for every mole of CO2 vented, a corresponding mole of ethanol is produced. By measuring the cumulative amount of CO2 vented from the sealed fermentation bag, it is possible to estimate the amount of ethanol produced to that point in time.
The GOvent NET replaces the original vent valve with a vent valve with internal gas flow sensing. Any gas (CO2) from the liner can only be released through the vent valve. The volume of CO2 released (compensated for temperature, pressure, and humidity) is measured continuously. Cumulative gas volume measurements are transmitted to the NET controller and displayed on the control screen. The estimated ethanol production and concentration in the liner can be viewed on the GOfermentor internet NET app (Android or iOS).
Predicted vs. Measured Ethanol — Within ± 0.25% v/v
GOvent NET — Gas Volume Sensor
The GOvent NET replaces the standard vent valve and clamps to the fermentation liner using a 2-inch Triclamp. The gas volume computer connects via cable to the NET controller. New NET devices can be ordered with gas measuring vent instead of the standard vent. Older units (prior to 2022) require a simple controller box retrofit.
Technical Details
| Function | CO2 gas flow measurement with ethanol estimation |
| Sensing | Internal gas flow sensor, compensated for temperature, pressure, and humidity |
| Accuracy | +/- 0.25 %v/v ethanol (validated across multiple varietals, 12-1,100L volumes) |
| Connection | 2" Triclamp (replaces standard vent valve) |
| Gas Release | Automatic actuation by controller + overpressure safety release |
| Monitoring | Free mobile app (iOS/Android) + controller display |
| Dimensions | 11 x 7 x 5 inches |
| Weight | 2 lbs |
| Compatibility | GOfermentor NET (new units); retrofit-able to pre-2022 models |
| Price | $495 |
Manuals & Downloads
View all manuals and resources on our Support page.