One research has it that there are about 1,308 operational gas pipelines in the world. These pipelines are used to transport natural gas across cities, countries, and continents. Yet, with the rapid energy transition happening, it is important to rethink the future of gas pipelines. And while that rethinking has been happening amongst business leaders, opting to abandon all natural gas pipelines does not seem like a viable solution, especially considering the critical role gas plays as a transition fuel for many developing economies and even how key it is for heating, transportation, and power supply in more developed economies.
For instance, one of the arguments by sponsors of the Spire STL natural gas pipeline in the US is that shutting it down will make people die of cold during the winter since it is vital for heating. Thus, while the transition is at play, with efforts to move more away from fossil fuel sources and replace them with renewable energy, we will still see natural gas infrastructure being funded and constructed over the next decade. What we do with this infrastructure, in the long run, is the important question.
It is no longer news that hydrogen is the fuel of the future, as it is clean and has the potential to power heavy machinery. While there are various forms of hydrogen – grey, blue, pink, green – the ultimate focus is on harnessing green hydrogen for commercial consumption. Yet if hydrogen is to be taken seriously, we have to think about transportation infrastructure from now- an important part of the energy value chain. While hydrogen can be transported as a liquid in thermo-insulated containers, as gas in high-pressure containers, or as methanol or ammonia, the most cost-efficient method is via pipelines.
Even at that, commencing projects today to construct pipelines solely for hydrogen delivery does not seem economically prudent since the technology for utilising hydrogen large scale is still developing in many parts of the world. Thus, a better approach is to repurpose new natural gas pipelines from the get-go to handle hydrogen transportation. With gas use likely to reduce by 2030 in Europe- a prime destination for export gas- there is a possibility of gas pipelines being empty or running at half capacity soon.
The obvious solution is, pass hydrogen through these gas pipelines. However, as the characteristics of hydrogen and natural gas are different, passing hydrogen through a pipe designed specifically for natural gas may destroy the pipeline structure. According to a 2013 study from the U.S. Energy Department’s National Renewable Energy Laboratory (NREL), it could “weaken metal or polyethylene pipes and increase leakage risks, particularly in high-pressure pipes”
To deliver hydrogen, these pipelines would have to be modified to do so. Research into the conversion of natural gas infrastructure for hydrogen use has revealed that while converting these natural gas pipelines to deliver the only hydrogen would require more significant modifications, and of course be more expensive, converting them to carry a blend of natural gas and up to 15% of hydrogen would only require modest modifications to the pipeline. According to Jussi Heikkinen, Director of Global Growth and Development at Wärtsilä , a leading energy solutions company, speaking on the need to modify pipelines to transport hydrogen, “When you go beyond 25 percent hydrogen in the fuel, in most places in the world, you’re no longer able to use the same equipment.”
It appears then that constructing natural gas pipelines with a hydrogen future in mind would solve the challenge of having to repurpose these pipelines in the future. The sponsors of the controversial Nordstream 2 pipeline appear to be seeking to set the pace here as its sponsors have revealed that they are considering modifying the pipeline to accommodate the delivery of hydrogen in the future. Another pipeline that has the opportunity to get in the front of the transition infrastructure line is the 5,660 km Nigeria-Morocco Gas Pipeline (NMGP) for which construction began only three months ago.
While it may not be feasible to aim to construct the NMGP as a 100% hydrogen capacity pipeline, as it would involve significant costs that were not originally factored into project costs, constructing the pipeline to accommodate a blend of hydrogen and natural gas is a possibility, and one that will not just reduce greenhouse gas emissions but will also defray the cost of building new dedicated hydrogen pipelines or other costly delivery infrastructure for commercially scaling hydrogen from Africa, thereby keeping energy costs in the future low. Additionally, Nigeria has more potential for green hydrogen- which is sourced from renewable energy- than Russia has with the Nordstream 2 proposal, so it is fitting to make these considerations in the construction of the NMGP.
To achieve the transition, all natural gas pipelines being constructed should be done to accommodate a blend of hydrogen. This way, a move to 100% hydrogen capacity would cost less and may only require incremental work as opposed to a start from the scratch.