North-South interconnector delays could push up electricity prices, warns Engineers Ireland

Switch to ‘hybrid generation’ needed in transition to climate-neutral power

The proposed North-South interconnector is crucial for the security of Ireland’s energy infrastructure, but delays mean its costs are escalating, which combined with power system constraints will have knock-on effects on electricity prices, according to Engineers Ireland (EI).

Ireland continues to be in the throes of an “energy trilemma” — trying to keep energy supplies secure and affordable while increasing sustainable energy production, its latest electrical energy review has warned.

EI calls for rapid scale-up of green hydrogen (produced from renewables) and hybrid generation systems, which can in time switch to burning green fuels.

Offshore wind

The report issued on Tuesday also calls for a flexible grid so Ireland can play its part in creating a European supergrid by exporting its excess power generated from renewables, notably offshore wind.


Retrofitting of thermal generation (using coal, oil and gas) power stations to be able to burn green fuels, such as green hydrogen, biomethane or biomass, will enable them in time to become carbon-neutral plants, it added.

It supports the provision of liquefied natural gas (LNG) and regasification units as a “near to medium-term solution to providing energy security ... to prevent possible future disruptions to gas supply”.

In addition, it calls for consideration to be given to removing statutory barriers to domestic nuclear power deployment — including reviewing the 1999 Electricity Regulation Act to enable a discussion on the option. “This would allow for a more informed process on the potential for nuclear in the future of Ireland’s electrical energy supply.”

It notes that North-South interconnector costs have increased from €331 million in 2021-22 to €835 million for 2022-23, while so-called market imperfection — constraint costs — was arising from frequent constraints on the use of the cheapest and cleanest sources of electricity generation in the system to maintain a stable grid.

“These operational constraints are due to a number of factors, specifically including the absence of the North-South interconnector, but also issues such as the lack of low-carbon sources of system stabilisation,” it says.

This should come in the form of adequate inertia, a form of energy storage that addresses imbalances between supply and demand on electricity grids over very short periods, but with the shift to renewables grid inertia is reducing.

With one million additional people living in Ireland by 2040, delivery of island-wide infrastructure should be a strategic priority, it said.

“Ireland needs to move from our current situation of being heavily dependent on imported energy to becoming much more self-sufficient, with the ultimate aim of becoming a net exporter of energy,” said EI president John Power.

Neighbouring countries

To do this the country’s electrical energy requirements for 2050 need to be identified, including “a diverse portfolio of green energy zero-carbon sources, a broad collection of interconnections with neighbouring countries, and a robust and flexible electrical energy grid”.

“We should also look beyond our island to the possibility of us playing a part within a European supergrid and becoming a net exporter of sustainable energy. Delivering on these ambitions will require a combination of technical expertise, planning and political determination,” said Mr Power.

“Historically, Ireland has a low-level electrical grid which is no longer fit for purpose as the demand for electrical energy has increased,” he said. “Additional high-level infrastructure is required. However, planning delays, as well as public and political challenges, have impeded the development of this critical energy infrastructure.”

Mr Power added: “Ireland’s economy depends on energy infrastructure which is secure and reliable and that will meet current and future needs. Engineers in Ireland need public and political support to develop suitable infrastructure and energy sources.”

He welcomed actions brought forward by Minister for Public Expenditure Paschal Donohoe, “which will expedite infrastructure projects and reduce the administrative burden in delivering major capital projects” under the National Development Plan.

‘Resilient’ system

Ireland’s grid capacity problem, said Mr Power, was equivalent to road traffic over-relying on secondary roads, when motorways were needed. Gridlock was the inevitable consequence, while the right level of inertia was an essential foundation in having “a resilient and scaled-up grid system”.

EI said a solid plan was needed for getting rid of fossil fuels, acknowledging “that can’t happen overnight”.

This should entail getting rid of coal and oil first, and including LNG “only to transition” as it was critical to energy security and independence.

On current planning problems, Mr Power said the system was “too long and ponderous” to enable major infrastructure projects to be completed within a reasonable period. It was inevitable big projects would be unattractive for some, but politicians need to take a broader view, he believed.

As major players in the Irish market, he said the ESB and EirGrid were hugely committed to enhancing energy efficiency but they were faced with difficult problems, typified by the North-South interconnector issue.

Their report, he said, reinforced the message for government that as a small island, energy independence would benefit everyone including future generations. “People are inclined to think, it will always be rosy with industry and jobs,” he added, but without an efficient grid that could be undermined.

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times