What challenges are there in creating a renewables-led European super grid?

2 Jul 2020

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Nations across Europe are rapidly building renewable energy sites for their national grids, but challenges lie ahead.

With the EU’s Green Deal now in full swing and countries across the continent agreeing to slash their greenhouse gas emissions significantly, a revolution is underway to connect nations to cleaner electricity. While the most obvious form of this is the rapid production of renewable energy sites, such as wind and solar farms or hydroelectric dams, a less discussed and challenging task is getting renewable electricity on the grid.

For the last century, we have lived with the concept that national grids are powered by a largely centralised, limited number of fossil fuel power plants. Now, adding dozens – if not hundreds – of smaller solar farms or wind farms to a grid poses a complex and difficult problem.

These kinds of smaller renewable energy sites were recently put forward by the Economic and Social Research Institute (ESRI) as a cost-effective way of achieving carbon emission reduction targets as they are less likely to cause local unrest in the same way that larger projects could.

One EU-wide project hoping to find a way to create a pan-European grid that would provide a steady supply of renewably sourced electricity is EU-SysFlex. Established in 2017, the project is being delivered by a broad energy sector consortium from across Europe and is led by Ireland’s electricity grid operator EirGrid.

It receives funding under the EU’s Horizon 2020 programme and involves 34 organisations from 15 countries across Europe, with a budget of €26m. While Ireland’s electricity connection to the EU was put at risk due to Brexit, Ireland is soon to play an integral role in the pan-European grid concept.

Last year, it was confirmed that the EU will contribute €530m out of a total cost of €1bn into the Celtic Interconnector project, which will link the Irish electricity grid with Europe via France through an underwater network. Once completed, its 700MW capacity is expected to power 450,000 households.

Using the old world for the new

Some estimates suggest that offshore wind infrastructure in Ireland could one day supply 5pc of Europe’s electricity needs, meaning a stable grid that can get that electricity where it is needed fast is essential to the EU’s targets set by the Green Deal.

Speaking with those connected to EU-Sysflex, one of the most pressing challenges the project is trying to solve is network congestion when renewable electricity is in significant supply, such as during a storm or intense sunny periods.

Its studies indicate significant power flow control and voltage stability issues in both the all-island and the continental-Europe system.

In one recent report, EU-Sysflex found that a system services-based incentive mechanism can potentially be used to help ensure that the old-world model of grid design is still workable in the new renewable-friendly world.

“In addition to developments in renewable electricity, there is also a trend towards sector coupling with, for example, increased electrification of heat and transport, which is seen to be an enabler of the power system transition,” the authors wrote.

“While this is clearly an advantage and an opportunity, this can also create challenges for the transmission and distribution networks. Distribution networks in particular were not designed for accommodating embedded generation and this can lead to the need for expensive infrastructure investment.”

Importance of interconnected systems

EU-Sysflex said recent focuses on issues of inertia and ‘firm frequency response’ – a service provided to quickly reduce demand or increase generation to help balance the grid and avoid power outages – are creating a path to the solutions a continental grid will need.

Speaking earlier this year about what happens when the EU-Sysflex project ends in 2021, its project manager, John Lowry, said it will “help inform future EU policy direction and design of future projects in research and innovation”.

“It is hoped that EU-Sysflex will help support and improve EU competitiveness, providing opportunity for technology providers and industry,” he added.

Hoping to build on the research efforts of projects such as EU-Sysflex is the European Network of Transmission System Operators for Electricity (ENTSO-E) and the European Distribution System Operators (EDSO). EirGrid is one of 42 electricity transmission system operators from 35 countries across Europe working to create legal and infrastructural frameworks for the objective of a pan-European grid built with renewables at its core.

“Innovation, integration and efficiency are key to achieving the EU climate goals and meeting European energy consumers’ needs,” said ENTSO-E’s secretary general following a recent report launch.

“A hybrid energy infrastructure – consisting of a system of interconnected systems – is part of that vision.”

Colm Gorey was a senior journalist with Silicon Republic