Energy Institute

Why do we need new power lines when demand for electricity will not return to boom levels until 2019 at the earliest?

The need for new power lines is closely linked to rising demand for electricity and the sustainable development of Ireland’s economy.

Power lines transport electricity from where it is generated to its point of use.  The main reasons for new power lines and the expansion of the electricity network are to:

  • Meet the electric power requirements of economic growth
  • Realise economies in meeting the electricity demand from consumers
  • Exploit our renewable energy resources
  • Decarbonise the electricity system and the economy.

All four factors are present today as electricity demand recovers and is set to grow into the future (Fig 1.).  A secure, affordable and environmentally acceptable electricity system is at the core of efforts to meet the needs of our growing population, increased affluence and greater industrial output.  Ireland’s GDP grew by 6.5% in 2015 and the demand for electricity grew by 1%.  New power lines have to be planned for well in advance given the time it takes to permit and construct them. Thus much of the debate around the need for new power lines is based on expectations of what will happen.

Figure 1. Total Electricity Requirement Forecast for Ireland

Eirgrid/SONI (2016) All Ireland Generation Capacity Statement 2016-2025. Available Online

  • Historical
  • Med
  • Low
  • High

The growing demand for electricity, in every year but one from 1927 to 2008, was the most powerful driver of investment in the national electricity grid and distribution system. Electricity demand dropped with the onset of the recession of 2009 and while now well below its peak, it is recovering. According to the latest forecasts it is expected to reach its 2008 peak in 2019 1 (Fig 1).

The Commission for Energy Regulation (CER) regulates investment in the electricity transmission and distribution network. Its approval of expenditure is around five-year development plans submitted by EirGrid and ESB Networks. These plans rely on forecasts of electricity supply and demand that are in turn affected by Government policy, economic development, innovation and technology. Thus investments are approved by the CER against the background of what is likely to happen rather than what is certain. There is always some risk that unforeseen factors or events will frustrate part of the purpose of the investment. It is important on the part of CER to ensure the right level of investment because the social and economic cost of under-investment and the resulting loss of or inability to supply new demand is high 2. Thus the CER decision paper on the five-year review of expenditure is the result of closely reasoned, widely consulted and publicly available documents.

While on the face of it we have enough power lines to meet current and projected demand to 2020 or thereabouts, there are other factors driving the need for new power lines.

If we are to have significant job creation in regions and rural areas then a 21st Century grid and power lines are needed to power the factories and offices that will create local employment 3.

The National Risk Assessment 2014 points out that “Balanced economic growth is partly dependent on the timely provision of infrastructure in the right locations. If this does not occur, then there will be negative consequences for indigenous job growth and Foreign Direct Investment (FDI) opportunities and may lead to consequent regional imbalances.” 4

With a view to maintaining Ireland’s attractiveness to investors, the Enterprise Agencies (Enterprise Ireland and the IDA) place a strong emphasis on the cost-effective provision of electricity infrastructure in their policy submissions to Government 5. Attracting industry requires a high quality, competitive and reliable power supply so new grid infrastructure plays a key role in spreading new jobs, industries and economic opportunity across the country 6,7. Other dedicated new power lines like interconnectors are needed to make our electricity system more cost-effective and secure. For example, the East-West Interconnector links Ireland to the larger system in Britain, so far helping to push down wholesale electricity prices 8. It is projected that a second North-South connection will result in savings of some €20m a year to customers on the island of Ireland by 2020, increasing further into the next decade 9(Fig 2). Continued investment in links to neighbouring jurisdictions is also important for security reasons and to deliver the benefits to Ireland of the European aspiration for a Single Electricity Market 10. The transmission system has to expand to facilitate increased supply and to ensure that the cheapest power plants can be tasked to produce power no matter where they are on the island.

Figure 2. Proposed interconnector between Northern Ireland and the Republic of Ireland

We also need power lines because our power plants are distributed all over the island (Fig. 3). This dispersion was deliberate and aimed to capture a resource (wind and peat in the Midlands), avail of deepwater port facilities (coal at Moneypoint), locate close to demand to reduce losses (Poolbeg and Huntstown in Dublin, Aghada in Cork) and to optimise the investment in the electricity system by balancing grid and power station investment.

The electricity grid allows power to be transferred from one part of the country to another depending on what plants are in operation and the demand in cities and towns across the country 11.  Suitably placed power lines enable the growing demand for electricity to be met more effectively by;

  • Facilitating competition between generators
  • Enabling areas rich in wind to develop by providing a route to market, and
  • By providing for contingencies such as the necessary maintenance, inevitable breakdowns and plant outages that occur from time to time.

Figure 3. Registered capacities at generators and interconnectors over the country of Ireland

EirGrid/SONI (2015) All-Island Generation Capacity Statement 2015-2024. Available Online

Eirgrid provides an up to date overview of electricity generation and supply in Ireland on their smart grid website 12. The required movement of power across such a wide area means there are extra charges and care involved in the transmission of electricity.

The nature of electricity generation in Ireland is changing with the deployment of renewable energy.  New power lines are required to connect new sources of electricity supply such as wind to the grid as they replace conventional generation units in meeting the demand for electricity across the country.

A modern and reliable electricity supply with renewables on-stream is appealing to many global technology companies and can help attract new industry and jobs. Recent investments in data centres by Apple and that announced by Facebook have relied on spare capacity in the existing infrastructure. As that capacity is committed future choices for locating similar developments narrow to the point where unless additional capacity is provided the option to attract new industry may be lost. Thus we need power lines to meet the anticipated new demand for electricity from industry and business as the economy and employment grow.

Finally, Ireland has demanding obligations under legislation implementing Europe’s 2020 targets and electricity will play an important part in delivering a sustainable future and decarbonising Ireland’s energy system 13,14,15. Developing Ireland’s electricity grid is essential to meeting these objectives. By reducing the levels of blockages and congestion on the network, which results in constraining and curtailing generating plant operation, the system can operate more efficiently lowering wholesale energy prices. The Government target of ensuring that 40% of Ireland’s electricity use is from renewable sources by 2020 means an expansion of the transmission and distribution network to allow new renewable generators to connect to the system.

Figure 4. Electricity generated by wind farms in Irish Counties

Wind farms, which will provide the main contribution to meeting our 2020 Renewable electricity target 16, are for the most part situated away from the main centres of population and need to find a route to where their power is needed, a route to market (Fig 4). On a windy day, power lines allow electricity generated in one part of the country to be transmitted to where it is needed. On a calm day power lines allow gas-powered generated electricity to be sent to where it is needed because of a lack of wind. The Grid West project aims to capture the enormous renewable potential of the West and develop economic opportunity and jobs in the regions. It will require the construction of critical infrastructure in the West of Ireland 17. The capacity to service new demand for power has to be anticipated and planned for in advance 18.