East coast energy boost: The Kildare-Meath grid upgrade explained

30 Oct 2020

Michael Mahon. Image: EirGrid

EirGrid chief infrastructure officer Michael Mahon explains the options proposed for the Kildare-Meath grid upgrade to meet growing electricity demands in the east of the country.

In Meath, Kildare and Dublin, growth in economic activity and the addition of new large-scale IT infrastructure has increased the energy demands of the region. In response, EirGrid has proposed options for a grid upgrade.

This Kildare-Meath grid upgrade proposal presents five different technical approaches to linking electricity substations in Kildare and Meath – two key nodes in Ireland’s electricity network. EirGrid is now seeking public feedback on the proposal before furthering the project next year.

To find out more about this project, we asked EirGrid chief infrastructure officer Michael Mahon to talk us through the options and how people can give their views.

What does the Kildare-Meath grid upgrade entail?

The Kildare-Meath grid upgrade is a development that will link the electricity substations at Dunstown in Kildare and Woodland in Meath. These are two key nodes on the all-island electricity network. Earlier this month, EirGrid launched a public consultation on the project to seek feedback on five technical options for the project.

Why is this upgrade needed?

The Kildare-Meath upgrade will play an important role in contributing to our clean energy targets by enabling the use of more renewable energy, including electricity from offshore windfarms. It will help us achieve our goal of ensuring that 70pc of electricity comes from renewable sources by 2030. At present, 36pc of Ireland’s power comes from renewable generation, mainly windfarms.

The project will also help to transfer power more effectively to the east of the country and distribute it within the electricity network in Meath, Kildare and surrounding counties.

A significant number of Ireland’s electricity generators are in the south and south-west, where many windfarms and some modern electricity generators are located. The power they generate needs to be transported to where it is required.

Power is currently transported across the country on two high-voltage power lines from Moneypoint in Clare to the Dunstown and Woodland substations. Transporting more electricity on these lines could cause electricity supply problems throughout Ireland, particularly if one of the lines is lost unexpectedly.

The Kildare-Meath upgrade will therefore ensure that we have enough electricity to meet the growing demand for electricity in Meath, Kildare and Dublin. This growth is due to increased economic activity and the connection of new large-scale IT infrastructure in the region.

What are the options for this upgrade?

The five shortlisted options are: the upgrade of two existing 220kV overhead lines to 400kV; a brand new 400kV overhead line; an underground 220kV cable; and two options for a 400kV underground cable. All of these options are equally safe.

We have not yet made a decision on which technology option we will use for the Kildare-Meath upgrade but we do have to take a number of factors into our decision-making process. These include technical performance, economic performance and environmental impact. Studies to date have indicated that the upgrading solution is the emerging best-performing option.

For the upgrading solution, the towers and conductors on the existing circuits would be replaced or modified so they could handle a higher capacity and voltage. This option would also need new towers at some points along the route.

Studies show that this option has a very good technical performance though it does not perform as well as the new 400kV overhead line option, which would give more operational flexibility. However, its economic performance is good and it is the overall best performer in relation to environmental and socio-economic factors, compared with the other options. This option’s environmental impact is mainly related to its construction.

A new 400kV underground cable linking the two substations is the emerging best-performing alternative. Earlier studies questioned whether such an option would be technically feasible due to the length of the cable involved. However, further investigations have shown it to be feasible.

The cable would be installed in the Meath and Kildare road network. A trench up to four metres wide would be required to meet the power-carrying capacity of the circuit.

This option has some technical performance advantages that other options do not and the economic performance of this option is good in comparison to the other options. However, the amount of cable required for this option is a challenge and a risk. The operation of underground cables also needs more management than overhead lines to make sure they are safe and secure.

We are keeping an open mind when it comes to choosing our final technology option, taking all the above factors into account. We are also looking to hear from the public on these options as part of our consultation process.

What are the next steps in this process?

Feedback from stakeholders and communities is at the heart of our consultation process for project development. This process is based on a six-step approach to gathering and understanding the views of our various stakeholders, including members of the public.

Currently, we are at step three, which presents the different technology options. We now want people to get involved in our consultation on the Kildare-Meath grid upgrade, engage in the process and share their views on the project.

This feedback will help us to make a more informed decision on the type of technology and specific route for this project. However, we understand that this is an enormously challenging time for everyone so we are presenting ways to share information in a way that is safe for all of us, in line with social distancing restrictions.

Therefore, we are making it easier than ever to provide feedback. Participants can do this via email, online and over the phone.

Following the conclusion of step three, we will consult on where exactly the new infrastructure will be built in step four. We expect this to be in 2021.

By upgrading lines in the east of the country, this project will upgrade lives by ensuring a safe, secure, reliable and cleaner supply of electricity for years to come.

The public consultation on the Kildare-Meath grid upgrade is open until Monday, 14 December 2020.