As the world seeks to shift toward cleaner energy, the hydrogen market is likely to grow. Today, hydrogen is used in many different industries, whether it be in small volumes for space heating and food processing, or for large-scale consumption with chemical synthesis and petroleum refining. There is a new emerging market for hydrogen in transportation as fuel cell electric vehicles are beginning to arrive on the scene. As demand for hydrogen increases worldwide, its supply and delivery methods will need to improve.
Hydrogen is currently either produced on-site or delivered via truck or pipeline. For large scale consumers such as refineries, pipelines make the most sense as a delivery system due to their constant supply of hydrogen at relatively inexpensive rates. Trucks cannot deliver hydrogen fast enough and are expensive, while on-site production would be feasible only for a small segment of end-users. (Exhibit 1).
Exhibit 1: Global hydrogen demand outlook for applications with pipeline transportation needs (million tons per year)
Currently, pipelines are mainly used for large-scale industrial applications and refineries. However, refineries are beginning to become less of a factor for pipeline transported hydrogen and their demand is projected to continue to decline. This leaves the industrial plants as the main pipeline support application for hydrogen. According to Exhibit 1, we may see 46 million tons of hydrogen per year being transported via pipeline to these applications while only 34 million tons is going to refineries as soon as 2030.
Despite pipelines making the most sense for large-scale hydrogen transportation, there are currently many challenges. For one, there are not enough pipelines to use. There are currently three million miles of natural gas pipelines across the United States compared to only 1,600 miles of hydrogen pipelines. Because demand for hydrogen is still comparatively low to that of natural gas, people are hesitant to pay large upfront capital costs to build new pipeline systems that could transport hydrogen. However, recent solutions have been proposed to address the lack of hydrogen pipeline infrastructure.
One way of getting around the absence of hydrogen-specific pipelines is to use the preexisting natural gas pipelines. There still are problems with this solution that will have to be fixed. For instance, there is a need to control hydrogen permeation and leaks as well as the need for better hydrogen compressor technology. Hydrogen compressors would need to be installed to input hydrogen in the pipelines as the current compressors are designed for natural gas specifically. The largest obstacle, though, would be the steel and welding of the pipelines possibly becoming embrittled from large-scale exposure to hydrogen.
Embrittlement can be addressed by using a blend of natural gas with up to 15% hydrogen which may require minimal to no modifications to current natural gas pipelines. Also, pipeline infrastructure could be expanded using fiber-reinforced polymer pipelines which are cheaper to install than steel. The benefits greatly outweigh the costs as this solution would ultimately give the hydrogen industry a great supply source while preventing natural gas pipelines from becoming obsolete over the time frame needed for the energy industry to transition to cleaner options.
– Thomas Dennis and Utkarsh Gupta
