The Irish gas network holds a vital role towards accomplishing the government’s ambition for a carbon-neutral economy by 2050. The energy system of the future, with lower emissions, will demand an appropriate combination of electrons and molecules, says Gas Networks Ireland. Today, these molecules mainly consist of natural gas, though future plans suggest renewable resources such as carbon-neutral biomethane and green hydrogen will take its place.
As Cathal Marley, the chief executive of Gas Networks Ireland, highlights, the organisation is not selling or producing the gas, but rather managing a €2.8 billion network which includes 14,700km of pipeline, overground assets, and two interconnectors leading to Scotland. He estimates that by the end of the decade, if conditions remain constant, roughly 80% of the gas will originate from these interconnectors.
It should be noted that despite the domestic use being a well-known aspect of Ireland’s gas market, Marley mentions that it is predominantly used in electricity generation. On an annual basis, 58 terawatt hours (TWh) of gas is transported on the Irish network, with 60% of it used in power production, whilst 29% goes to commercial and industrial customers, leaving only 11% for residential households.
Marley further explains, on an average, gas generates 45% of Ireland’s power, and can reach up to 90% at times. He states, “Renewable energy forms such as wind are considerably inconsistent and that’s a reality we have to live with. There will always be a need for molecules to supplement unstable renewable power.”
Remaining dedicated towards achieving Ireland’s climate goals, Gas Networks Ireland has released its “Pathway to a Net Zero Carbon Network”, detailing their plans of transforming and resizing the current pipeline network for full decarbonisation by 2045.
In simplistic terms, the goal is to gradually phase out natural gas and substitute it with sustainable, carbon-neutral biomethane. Eventually, green hydrogen, which produces no emissions, will be incorporated as it becomes accessible. Marley highlights that large-scale hydrogen use is still some distance away, its availability being reliant on the advancement of offshore wind power in Ireland. He adds that any excess power from this energy source can be used to generate the gas.
Marley acknowledges, “We are only just starting to expand offshore wind power, a prerequisite for producing hydrogen on a large scale. The more immediate solution is biomethane.” As gas specialists who have been researching this field for around half a decade, he comments how they fully expect the government’s national biomethane strategy target of 5.7 TWh by 2030 to be exceeded after receiving 176 expressions of interest from prospective providers for between 14 and 15 TWh of biomethane.
Marley also details various benefits of the gas, describing biomethane as the ‘multi-tool’ of renewables. As a fully circular fuel, substances like slurry and food waste, usually problematic for the country, are converted to clean energy and the byproduct is high-quality fertiliser. This transformation not only offers farmers a chance to diversify but is also fitting for Ireland’s economy.
An additional bonus of biomethane is its indigenous status; it can boost energy security. Marley states, “The Corrib gasfield, currently providing 15 to 17 per cent of our gas supply, is dwindling and by 2030, it will only contribute 11 per cent. Biomethane can fill this gap and provide Ireland a clean, homegrown backup fuel source.”
Reflecting on Denmark’s experience, Marley believes that Ireland can follow suit. “Denmark’s gas network is comparable in size to ours. Since 2012, when they had no biomethane use, they have increased to 40 per cent of their gas coming from biomethane,” he explains. Marley and his team have visited Denmark several times to learn from biomethane producers, farmers, governmental bodies and other relevant parties. They have also brought along stakeholders from Teagasc, the government, Sustainable Energy Authority of Ireland, regulators, and customers who returned from the trips enthusiastic about the possibilities of biomethane.
The charm of biomethane lies in its chemical similarity with natural gas, allowing it to be directly funnelled into the network without the need for modifications. As Marley indicates, the network currently hosts five large-scale biomethane producers under agreement, a number projected to more than double by year’s end. Plans are underway for a central grid injection point in Mitchelstown, aimed at gathering gas from smaller producers for input into the network.
Scaled hydrogen production may be a future prospect, but Gas Networks Ireland is proactive in readying itself. Safety measures must be efficient, explains Marley, given the smaller size of hydrogen molecules compared to natural gas. Meticulous testing is key, considering the successful transport of hydrogen in places like the Netherlands and Germany doesn’t guarantee similar results everywhere else. Luckily, the modernity of the Irish network outshines many of its European counterparts. Collaboration with academia, including University College Dublin Energy Institute, shapes their exhaustive testing efforts at their in-house Network Innovation Centre.
The organisation’s research and trials indicate that a significant proportion of existing domestic appliances and energy-intensive industrial equipment could handle gas with a hydrogen content up to 20% without retrofitting. Marley expresses confidence that the network could transport such a blend without compromising on safety. Preparations are underway to ensure readiness for when green hydrogen becomes available.
Beyond its own network, the organisation extends its safety expertise and know-how to propel the early-stage industry. As part of the Celtic Hydrogen Cluster, the organisation envisions the Celtic Sea region as a leading global player in floating offshore wind by 2030. In collaboration with various energy producers and consumers, they are exploring the production, storage, and safe transport of hydrogen.
In the long-term, the network is expected to facilitate a mix of biomethane and hydrogen. A critical point is expected when the volume of hydrogen would necessitate a split network solution.
“The ultimate objective with hydrogen is to establish a specific network for this gas,” he asserts. “Numerous market studies highlight that the expense involved in repurposing gas pipelines is anticipated to be only 10 to 35 percent of the cost associated with constructing new hydrogen pipelines. Consequently, the modification of gas pipelines is likely to play a critical role in the global development of hydrogen networks. It is anticipated that we will eventually establish two separate networks for biomethane and hydrogen, a milestone we expect to reach fully by the 2040s.”
The goal set by Gas Networks Ireland for 2045 is to completely phase out the use of any natural gas within its network. “Our pathway document serves as a significant indicator of our aspirations to the biomethane industry. We plan to release another document soon, which will chronicle our journey towards decarbonisation in more detail,” he adds.
He continues, “From a company standpoint, these are exciting times. Having been a part of the energy sector for a quarter of a century, I am genuinely thrilled for the upcoming phase.”