It is well known that thermal mass flow meters are effected by gas composition.  Because thermal mass flow meters are effected by gas composition, many customers are concerned about how composition changes effect overall system accuracy. Through many years of experience with gas mixtures, we have seen that in many cases, a thermal mass flow meter is a superior method of measuring natural gas, even when changes in composition are encountered.  What we have found is that in many respects, our patented Dry-Sense sensor is measuring the “energy content” of the gas. Gas suppliers in general change compositions due to seasonal constraints, or availability of different sources of gas, but because they are focused on supplying a certain energy content, and our sensor is very sensitive to energy content, the mass flow meter readings remain accurate, even when the composition changes. Be sure to check out our sub-metering infographic to find out the secret to slashing your facility's natural gas bills.