Renewable wind and solar power are helping to reduce Ireland’s carbon emissions significantly, but they are not without challenges. Chief among them is intermittency. The wind doesn’t always blow and the sun doesn’t always shine. So how do we meet electricity demand when renewable sources aren’t fully available?
“One part of the solution is to store surplus renewable electricity in large-scale batteries,” explains Clare Duffy. “There are times when renewable sources provide more electricity than the country is using such as when it’s a very windy or sunny day. By developing electricity storage capacity, companies like ESB can keep a reserve of excess electricity, ready to be dispatched instantly at times when needed to deliver a consistent electricity supply.”
She outlines, “ESB believes that a secure net-zero energy system in Ireland by 2050 requires key elements: renewables, energy storage, and traditional backup generation.” This integrated approach will also deliver security of supply by reducing Ireland’s dependence on fossil fuels from more volatile parts of the world and allow us to develop “home-grown” energy from our own natural resources. “In a sense, we are trading off geopolitical risk for meteorological, so we are always going to need backup technologies to support renewables,” she notes.
As part of ESB’s net zero by 2040 strategy, Duffy’s team is developing investment options to provide energy storage, grid system services and backup generation assets to contribute to the security of supply in Ireland in the short term to medium term and support increased integration of renewable energy in the longer term.
From west Donegal, Duffy studied electrical and electronic engineering at the University of Strathclyde in Glasgow. “After graduating, I worked in the UK and US for a multinational engineering company for five years. In 1999, I had the opportunity to join ESB International working on overseas electricity projects. It was great to have a clear line of sight on the impact of our projects on people’s daily lives. We were often working in post-conflict or developing world countries, and it was then that I truly understood how a secure and reliable energy system was such an enabler to economic and social development — something I’d probably taken for granted before then.”
She values the experience gained during that time. “I’ve always said you can work anywhere in the world as an engineer. With ESB International I worked on projects in Europe, USA, Middle East, South-East Asia and Africa. You get deeper insights when you’re working in a country alongside locals rather than visiting as a tourist. It was a great opportunity for a young engineer.”
She took up a role as ESB’s UK general manager in London in 2011. “At that time, ESB was investing in UK generation assets as the UK and Irish markets were becoming more interconnected. It was an exciting and challenging time to work there as the UK was going through the most significant changes to its electricity market structure since the privatisation of the 1990s.”
Security of supply
“I came back to Ireland in 2016 and believe the country’s best way forward to meet our climate action goals is to continue to decarbonise our electricity generation using renewable energy and decarbonised fuels, and to increase the electrification of heat and transport, thereby removing fossil fuels from our energy system. Whilst there are other solutions being developed, electrification is the only proven pathway of decarbonising energy at scale. Again, there is a clear line of sight to our purpose in ESB and how we are investing in Ireland, driving us towards a secure and sustainable Net Zero energy system, enabling the green energy revolution in our economy and society. Having that clear purpose is a real motivating factor in working for ESB.”
“Battery storage plays a key role, and it helps in a number of ways,” she continues. “It takes excess power from renewables and stores it for later. If there is a shortage of power, it can respond within 120 milliseconds. ESB has shown its commitment to battery storage technology through active investment. We have over 300MWs of two-hour storage across five sites, enough to power around 200,000 homes. That represents an investment of €300 million.
“My team is working to develop a pipeline of potential projects around the country,” Duffy explains. “We are working with landowners to get access to sites, get the necessary permits and planning permissions in place, and line up the technologies required. We need to get the projects to a stage where we can bid for contracts. Some of these early-stage projects are stand-alone storage facilities and others are hybrid projects which would be developed near existing solar or wind farms which already have a grid connection.”
In addition to battery energy storage, her team is also developing backup generation. Globally, the next decade will be marked by an intensification of innovation in backup generation using non-fossil-based fuels that will move towards Net Zero carbon emission solutions. ESB has developed several backup generation options, including a new electricity generation station currently under construction in the Poolbeg Energy Hub, a stone’s throw from the 75MW battery energy storage project. ESB bought turbines for the new Poolbeg station that will run on natural gas initially and then with certain modifications will transition to decarbonised fuels as the fuel becomes more readily available. The co-location of multiple technologies that all have a role to play in the Net Zero future is characteristic of energy project development nowadays and the Poolbeg Energy Hub is a prime example.
She concludes by pointing to the essential role battery storage will play in the pathway to a decarbonised electricity system. “Meeting Ireland’s highly ambitious climate action targets will only be possible with a massive increase in renewable electricity generation. That will only be possible if we have sufficient battery storage capacity to meet demand when renewable electricity isn’t available. I’m proud to be part of ESB team that is helping to provide that storage capacity.”
To read more about ESB’s renewable energy plans visit esb.ie