| dc.description.abstract | Recently, the use of hydrogen-natural gas mixtures as a fuel, but also as a means of storing and transporting hydrogen from surplus electricity as a result of renewable energy production has drawn significant attention. One of the approaches to manage the intermittent nature of wind and solar generated electricity is to create, store and transport hydrogen in natural gas pipeline networks. Blending hydrogen into the existing natural gas pipeline network appears to be a strategy for storing and delivering renewable energy to markets. Adding Hydrogen to the natural gas requires considerations regarding combustion systems, as well as the impact on compressors and pipeline hydraulics. This paper addresses combustion issues with various levels of hydrogen in natural gas, the transport of these mixtures in pipelines, and the compression of these mixtures. Thus, the transport efficiency of the pipeline, the impact on pipeline capacity, and the capability of existing and new infrastructure to use natural gas – hydrogen mixtures as fuel are discussed. Used as a fuel, hydrogen-natural gas mixtures increase the reactivity, with increased flame velocity, reduced auto-ignition delay times, and a wider range of flammability. The handling of failed starts, where unburned fuel can be present in the exhaust system and may cause an explosion hazard, has to be addressed. Increasing hydrogen content also increases flame temperature which can lead to higher NOx emissions and mitigation strategies are discussed. Results from analysis and rig testing of the combustion components with hydrogen and natural gas mixtures are presented. | |
