Sensors for hydrogen concentration measurements in natural gas

摘要

The conversion of (renewable) electricity to hydrogen, also referred to as power-to-hydrogen (PtH), and its subsequent injection into the natural gas grid can increase the share of renewable energy in various end-use applications for transport, heat, and industry, where achieving higher renewable shares is technologically more difficult and more expensive than for power generation via fuel cells or hydrogen-powered generators. Moreover, by exploiting the huge storage capacity, hydrogen injection into the gas grid effectively decouples the energy supply (e.g., that which is produced from variable sources such as wind and solar power) from demand in time and in location. PtH can thus link the electricity transmission and natural gas grids, thereby enhancing energy security. However, the addition of hydrogen to natural gas influences properties such as compressibility, viscosity, density and heat capacity, which can have commercial impacts due to performance and safety concerns, especially with higher concentrations of hydrogen (>10 vol%). The effect on volume measurement, gas composition analysis, metering, and measurement of calorific value, especially for billing purposes or process control must be assessed. The availability of sensors for measuring hydrogen concentration in hydrogen-natural gas mixtures could support metering, billing, and modelling of these mixtures. Hydrogen sensors could also interface to industrial burner control systems to adjust operational parameters so as to optimize the combustion process. There are in addition safety concerns on the expanded use of hydrogen-natural gas mixtures. Accordingly, a study aimed at verifying the suitability of hydrogen sensors for use in natural gas has been initiated. In addition to performance verification, a goal of this project is to develop guidelines on how hydrogen sensors can be used in this type of application.