Growing amounts of renewables — wind and solar — have exacerbated the need for investment in expanding the grid network all over Europe.
In some countries the situation is more serious than others. In Sweden, for example, where wind accounts for about 8% of the country’s electricity generation supply, new wind power projects have been put on hold.
This is partly because the country lacks the infrastructure to transport surplus wind energy from where the majority of wind farms are built to capture the resource in its abundance, to places where the demand is. Building new transmission lines is seen as one of the main options to overcome this bottleneck.
Interconnectors are transmission cables for supplying electricity from one region or country to another. One country might be experiencing an oversupply of wind power but with an interconnector it could send the surplus to its neighbours.
The European Commission wants to have many more of these cross-border transmission cables linking up the various 28 member states, effectively pooling Europe’s electricity supply. To achieve this a new EU target sets out that all member states must achieve interconnection of at least 10% of their installed electricity production capacity by 2020.
While an admirable big-picture approach, the cost of dissolving Europe’s electricity borders by criss-crossing the continent with more long distance power lines is expected to be in the region of €40 billion ($44 billion) conservatively.
Think how many storage systems that could be bought — with plenty of change left over — which could expand the capacities of grids and, if planned well, provide a raft of ancillary services and benefits too.
An example of how expensive, as well as contentious, investments in new transmission lines can be is happening between France and Spain. The two countries already share an interconnector. France, heavily reliant on nuclear power-supplied electric heating, imports excess power from Spain in the winter and exports fairly cheap nuclear energy to Spain at other times.
After a number of years of back-and-forthing, the French and Spanish power grid operators have recently completed a second power line that will allow Spain to export some of its excess electricity generated from wind and solar to France rather than resort to building more thermal power stations to cover demand.
When it goes live in June, the cable, which crosses the Pyrenees mountains, where the two countries border, will double French-Spanish interconnection capacity to just under 3GW.
But to keep the Pyrenees unmarred by unsightly pylons the new DC interconnector, 65km in total, has had to be buried, at a cost of €700 million.
It’s an extreme case but goes to show that preparing and constructing miles of transmission cables can be an extravagantly expensive way to integrate more renewables into the grid.
Europe does need new interconnectors to help accommodate more wind and solar being built across the continent. But it raises the question of whether there should be a case made for an EU-wide policy that views energy storage as part of the bigger picture also.