From diesel to electric or somewhere in between, vehicles of all types ply our roads and motorways day and night. In our busy modern work culture, transport is an important day-to-day issue for everyone, with much improved public transport likely to be the solution. In this Cois Coiribe feature, Professor Rory Monaghan of the Energy Research Centre, Ryan Institute and School of Engineering examines the promise of hydrogen – one of the newest developments in sustainable energy. He explains his work toward bringing that promise to fruition through creation of a ‘Hydrogen Valley’, and how Ireland, with its enormous renewable energy resources, is ideally positioned to lead in this area.
Traffic. It is the one conversation topic that animates people in Galway more than the weather. To bypass or not to bypass, sin í an cheist! To the list of topics to be avoided in polite conversation with strangers, Galwegians should surely add the Galway City Ring Road, or GCRR, as the proposed bypass is officially known. While the resubmitted planning application makes its way through An Bord Pleanála at the speed of a Saturday afternoon drive along the Headford Road, it is easy to forget that a solution to our traffic woes already exists.
Public transport is having a moment
Transport for Ireland reported that 2023, the most recent year for which full figures are available, saw record use across Ireland of buses, trains, and trams, with passenger numbers exceeding pre-pandemic levels by over 5%. While progress is still stalled on the Metro North project to connect Dublin Airport to the city centre, other initiatives are speeding ahead. Dart+ will triple the length of Dublin’s electrified light rail network. BusConnects, an ambitious data-driven plan to expand bus network coverage, reliability, and punctuality, has seen surging passenger numbers in Dublin, and is now being rolled out in other cities. Across the country, passenger railway lines are being upgraded and doubled-up, stations are being extended, and plans are being drawn up to revitalise decommissioned lines, such as the Western Rail Corridor.
Galway has not missed the bus
Founded in 2016, CitySwift is a Galway-based mobility tech company that uses data to optimise bus fleet operations in Ireland, the UK, and as far afield as Hong Kong. Its deal with Transport for London will see its platform available to 9,000 buses serving 1.8 billion annual passenger journeys. Bus Éireann, Ireland’s public bus operator, switched all urban buses in Galway from diesel double-deckers to diesel electric hybrids, which are estimated to reduce emissions by over 30%. These new hybrids will be key to the rollout of BusConnects in Galway in the near future. Low- and zero-emission technology is not only cleaner, quieter, and more pleasant for passengers and people on the streets, but reduced diesel use insulates us from fare hikes due to volatile fossil fuel prices.
Why not full electric?
Athlone and Limerick have recently moved to full battery electric fleets. This is an excellent option where daily driving distances are relatively short, terrain is flat, and the electricity grid has sufficient capacity to support the power demand of fleet charging. The frequent stopping of buses additionally allows for battery recharging through regenerative braking. But what about longer journeys? Regional buses based in Galway serve towns such as Westport, Clifden, Gort, and Athlone. Intercity coaches based in Galway travel to Derry, Dublin, Cork, and back, several times a day. The prospects of replacing these diesel behemoths with battery electric models are currently dim, unless coach operators are willing to buy extra buses to cover long midday charging times. What is the solution?
A bright idea from the lightest molecule
The reason batteries struggle to move heavy-duty vehicles along long-haul routes is their low ‘energy density’. Energy density refers to the quantity of energy a technology can store in a given volume or mass. Relatively low energy density batteries mean an electric coach can either travel a long distance or carry lots of passengers and luggage, but unfortunately not both! It also means charging times in the range 30 minutes to 2 hours, compared to 5 to 10 minutes refuelling time for diesel.
This is where hydrogen comes in. Even though hydrogen is a gas that needs heavy steel or composite tanks to contain it, and a fuel cell or an engine to convert its energy to motive power (the energy used to drive machinery), its energy density is 3 to 4 times higher than that of batteries. This means hydrogen-fuelled vehicles can travel nearly the same distances as their diesel counterparts. However, the big challenge with hydrogen is getting it.
Despite being the most abundant element in the universe, hydrogen is notoriously difficult to come by. It cannot be considered a fuel, like oil, because unlike oil it cannot be readily extracted from the earth. Instead, hydrogen is known as an ‘energy carrier’, which must be created by pulling it from some chemically stable substance like water or fossil fuels. The energy needed to do this makes hydrogen expensive.
Obviously, using fossil fuels to create hydrogen makes no environmental sense, especially in Ireland, where we have very few fossil fuels to begin with. Any hydrogen used in Ireland should therefore come from electrolysis. This involves the use of electricity, preferably renewable, to split water. Ireland is ideally positioned in this regard because of its enormous renewable energy resources – far in excess of long-term electricity demands – which are mostly untapped. Surplus wind and solar power could be diverted to electrolysis to make hydrogen to decarbonise the parts of our energy system unsuited to electrification, like coaches, trucks, factories, cement works, and data centres. In this vision, hydrogen is a store for renewables, essentially charging up on windy days, releasing its energy on calm days.
Hydrogen valleys as the solution to a chicken-and-egg problem
Despite hundreds of academic studies highlighting the importance of renewable hydrogen to full energy system decarbonisation, progress on the ground has been slow. Fleet operators will not buy expensive hydrogen-fuelled coaches until a reliable hydrogen supply exists, but suppliers will not build expensive electrolysers until they have committed hydrogen buyers. All the while, technologies remain expensive while deployment, and therefore production volumes, remains small. What comes first? It’s chicken-and-egg for the renewable age. This is where the European Union has stepped in and created the Clean Hydrogen Partnership, whose mission is to fund the deployment of clusters of hydrogen producers, distributors, dispensers, and users. In the lexicon of Brussels, these clusters are known as ‘Hydrogen Valleys’.
We at University of Galway are leading SH2AMROCK, a 5-year, €54-million project to build, operate, and grow Ireland’s first Hydrogen Valley. It incorporates all elements of the green hydrogen value chain, from production and storage to distribution and dispensing, and on to end-use. It has a consortium of 28 members from 12 countries with funding of €7.5 million from the Clean Hydrogen Partnership, as well as €0.5 million from UK Research and Innovation.
SH2AMROCK will see renewable hydrogen production at a wind farm in the midlands, transportation of hydrogen to Galway Port, operation of Ireland’s first purpose-built hydrogen refuelling station, and use of hydrogen to decarbonise Bus Éireann’s regional and intercity coach fleets, as well as local freight, haulage, and logistics fleets. The project will see hydrogen used to decarbonise high-temperature heat demand at a facility in the Galway region operated by Colas, a leading provider of end-to-end solutions in the road maintenance sector in Ireland, and to conduct zero-emissions flight trials between Connemara and the Aran Islands with Aer Arran Islands. Of crucial importance, SH2AMROCK will be the seed from which a nationwide hydrogen network can grow.
Positioning Galway as a European leader
SH2AMROCK encapsulates University of Galway’s ethos of: Purpose, People, Place. It builds upon the work of Dr Pau Farras, Dr Thomas Van Rensburg, and Dr Brendan Flynn, and my own work in previous EU-funded hydrogen projects, including HUGE, SEAFUEL, Green Hysland, GenComm, and HEAVENN.
In conclusion, the SH2AMROCK project not only offers a blueprint to leverage renewable resources to tackle local challenges but also paves a way for sharing findings and insights worldwide.
By reducing diesel imports and pollution emissions, every kilometre travelled on hydrogen-powered vehicles brings Ireland and the world closer to a more sustainable future. Making Galway’s public transport more sustainable will undoubtedly enhance the quality of life and work in the city. As one of only 18 Hydrogen Valleys in Europe, SH2AMROCK places University of Galway at the forefront of impactful research globally, while contributing to a solution for our beloved city’s infamous tailbacks!
