Natural gas is often called a "bridge fuel" to cleaner energy production, but a researcher in the Netherlands believes that natural gas pipelines can be a bridge for the renewable gas hydrogen.
Natural gas pipeline and distribution system operators currently have no guidelines for accommodating the injection of hydrogen into their networks. Netherlands-based consultancy DNV GL has begun a global industry project called HYREADY, with participation from natural gas value chain participants and technology providers, in order to develop standards for hydrogen injection.
"The 'HYREADY' initiative will encourage the industry to "be ready for hydrogen" by developing practical processes and procedures for the introduction of hydrogen to the grid," the company said.
"We have seen an increasing number of projects needing access to natural gas infrastructure for renewable gases," DNV GL Project Manager Onno Florisson. "With multiple organizations having the same objective, our industry guidelines will address the 'how-to' questions for gas system operators so that they can be confident both in preparing their natural gas grids for the accommodation of hydrogen and in the consequences related to hydrogen injection."
Florisson said any hydrogen introduced into the pipeline grid would be delivered to end-use applications as part of the overall gas stream. Earlier work in a project called NATURALHY sought to determine how pipeline infrastructure might successfully accommodate hydrogen.
This project found that depending upon the type of steel from which high-pressure pipelines are constructed, the pipelines could be used for gas mixtures containing up to 50% hydrogen, Florisson wrote in a paper on the project. "Safety related to the transmission, distribution and end use of natural gas is not significantly compromised compared to the current situation with natural gas if up to 20% of hydrogen is added to natural gas," he wrote. "Additions up to 50% might be feasible but must be assessed case by case."
According to Florisson, the maximum amount of hydrogen that can be injected into a natural gas system while allowing for proper end-use equipment performance depends upon the appliance type and condition as well as upon local natural gas distribution conditions.
Hydrogen could be sourced using sustainable energy sources, such as wind power, and it is a component of syngas, which is produced by the gasification of coal or biomass.
To successfully introduce pure hydrogen (e.g., from power-to-gas) and hydrogen containing mixtures (e.g., syngas) into natural gas grids, the impact and acceptability needs to be assessed to evaluate among others the performance and safety of end-user appliances, system integrity and integrity management, energy transport capacity and compression efficiency. This is one of the aims of the HYREADY project.
The project will run for two years and is split into four work packages: transmission systems, distribution systems, end-user infrastructure and appliances (both domestic and industrial) and the design of a hydrogen injection facility. The impact of hydrogen on the natural gas system will be addressed on both a component and system level. HYREADY will be based on existing knowledge; there is no experimental work foreseen to be carried out in the framework of this project.