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Interconnector
Key takeaways
- Interconnectors are high-voltage cables that allow electricity to flow between Great Britain’s grid and other countries’ grids.
- GB has interconnectors to France, the Netherlands, Belgium, Ireland, Norway and Denmark.
- Flows respond to price differences between markets — and changes in those flows move wholesale prices on either side.
What is an interconnector?
An interconnector is a high-voltage subsea or overland power cable that links the GB electricity system to another country’s system. They let electricity flow either way, depending on where the price is lower / where there’s spare generation.
GB’s major interconnectors connect it to France, the Netherlands, Belgium, Ireland, Norway and Denmark. When GB prices are higher than the other side, power tends to flow in; when GB is cheaper, it flows out.
Why interconnectors matter for prices
They add to or subtract from GB’s available generation capacity hour by hour.
Unexpected outages or flow changes show up quickly in day-ahead and intraday prices.
Greater interconnection generally reduces price volatility — but at extremes (cold snaps, low wind across NW Europe) all the connected markets can move together.
