The Larne area is the only location on the island or Ireland with suitable geology for salt cavern gas storage. Gas will be stored in seven storage caverns, each approximately 80m in diameter and 185m in height, which will be created within a layer of salt located approximately 1,500m beneath Larne Lough. The salt layer has high purity and low overall insoluble content and is suitable for cavern construction over its entire thickness.
The proposed gas storage facility will provide the island of Ireland and the wider UK with security of energy supply. Currently since the closure of Centricas Rough facility, the UK has just over 1% of its annual demand in storage compared with our European neighbours who have 20–30%. This is leading to increased volatility in the market which will at best lead to substantial price increases for consumers and at worst loss of power. The new facility will provide security of supply for up to 14 days.
The proposed site is ideally located close to the sea and already possesses the two main supporting infrastructural requirements for a gas storage facility – a source of power (adjacent to Ballylumford power station where the electricity grid is very strong) and a connection to the main gas network (the Ballylumford pressure reduction station is the connection point to the Scotland-Northern Ireland gas pipeline).
In 2013 the project was given PCI status by the European Commission and included on a Europe wide list of the most important energy projects. PCI status means recognition by the European authorities that the Islandmagee gas storage project brings benefits not only to the Member State in which it is located but to a much wider area. This provides confirmation of the importance of the project at a European level.
PCI status means that the project must be given priority and quick passage by the relevant Member States in the permitting process, and cooperation in its development as well as being eligible to apply for significant financial support from the European Union.
In 2017, the project’s PCI status was renewed for a further two years– the only gas storage project in Western Europe to have this designation. The EU has provided grant funding to the project for the FEED. Towards the end of 2018 an application was lodged to continue PCI status on the 2019 – 2021 list.
The project will create permanent jobs, generate temporary employment with construction activities and knock-on indirect business for support services and many more.
Gas storage also has the potential to reduce volatility in energy prices – with the option of purchasing gas for storage when prices are low for use or sale when prices are higher.
The project is being developed as a commercial venture, with no cost incurring to the energy consumers
Wider economic benefit jobs
Seven storage caverns, each approximately 80m in diameter and 185m in height are proposed at Islandmagee. The caverns are created by a technique known as ‘leaching’ or ‘solution mining’, which dissolves the salt, under controlled conditions, and creates a cavern deep underground in the salt layer in which gas can be stored. The facility expects to have an injection capability of 12 million cubic metres per day of gas and a maximum withdrawal capability of 22 million cubic metres of gas per day.
The diagram below illustrates the proportions and depth below ground of the proposed caverns.
The use of salt strata to create underground storage caverns deep underground is one of the safest and most environmentally friendly methods of storing large quantities of natural gas.
Gas storage technology is tried and tested all over the world, with more than 300 salt storage facilities in operation, with more under construction. Currently about one third of the operational facilities are located in Europe, with the majority in Germany, a country with some of the most stringent safety requirements.
The Islandmagee facility will conform to the highest safety regulations, and will include a number of safety features, including sub-surface safety valves, to isolate gas stored in the caverns.
Brine will be discharged whilst being monitored 24/7 to ensure the rate of discharge is controlled at all times, should the rate of discharge change outside the licensed conditions the discharge will be stopped.
The strategic benefits of a project such as the Islandmagee Storage project have long been recognised by both the NI and ROI governments and regulators as well as more recently by the European Union.