Grid congestion reducing German North Sea wind production – Tennet
Grid congestion reducing German North Sea wind production - Tennet | Windpower Monthly
Since the DolWin6 offshore grid connection was completed in September 2023, Tennet's offshore transmission capacity in the German North Sea has risen to more than 8GW, from just over 7GW in the previous year.
Despite this increase, congestion in the German onshore electricity grid has led to “large wind farms in the North Sea [having] to be shut down more and more frequently”, according to Tim Meyerjürgens, Tennet’s chief operating officer.
There are hardly any large conventional power plants in northern Germany that could be throttled instead, he explained. “As a result, the associated redispatch slows down the generation of offshore wind power,” affecting both the amount of electricity fed into the grid and electricity prices.
Total wind energy transmission in Germany in 2023 was 149TWh, up from 123TWh in the previous year, due to a significant increase in onshore wind power generation.
North Sea offshore wind accounted for around 19TWh, down from 21TWh in 2022, while offshore wind from the Baltic Sea – part of the grid managed by 50Hertz – amounted to around 4TWh.
The overall share of offshore wind power from the German North Sea in total wind energy yield fell for the first time – to 13% in 2023, from 17.2% in 2022.
Meyerjürgens argued that this shows that Germany must “continue to accelerate the expansion of the grid and the major electricity highways” to enable the potential of the North Sea to “be utilised efficiently as soon as possible”.
In the Netherlands, nearly 12TWh of offshore wind energy was supplied via Tennet’s offshore grid to the onshore network in 2023, up from 8TWh in 2022.
The increase was primarily due to the commissioning of the Hollandse Kust (noord) offshore grid connection system and the corresponding expansion of offshore wind farms in 2023. Tennet’s transmission capacity in the Dutch North Sea increased to nearly 4.7GW.
The company added its voice to a joint letter on 24 January by a broad alliance of social parties urging the Netherlands to pursue a consistent grid expansion policy, as talks continue on the formation of a new coalition government following the recent election win of the far-right, anti-wind Party for Freedom (PVV).
“Standing still is not an option,” Tennet said in a statement. “We are investing more than €10 billion annually in the Netherlands and Germany in the coming years to expand the electricity grid. This means we are fully committed to building, building, building.”
Tennet noted that this expansion required laying cables “from Groningen to Maastricht every month until 2050” and opening up one in three streets in the Netherlands for work.
The TSO called for a “smart energy supply, tailored to (local) generation, use and storage” to improve grid flexibility.
Related Knowledge Center: Offshore wind energy
Over the next decade, U.S. offshore wind power is expected to grow from a single 30-megawatt wind farm off Rhode Island to more than 2,000 MW of capacity along the Atlantic Seaboard. There are contracts for wind power off the coasts of Massachusetts, Connecticut, New York, Maryland, New Jersey, Rhode Island, and Virginia.
The National Renewable Energy Laboratory has estimated the United States has over 4,000 gigawatts (GW) of offshore wind potential, enough to power the country four times over.
The growth in part being spurred by state solicitations, including in New York, where then-Gov. Andrew Cuomo (D) set a commitment of 9,000 MW of offshore wind by 2035, and in Connecticut, where in June 2021, Gov. Ned Lamont (D) signed legislation authorizing the construction of 2,000 MW of offshore wind by 2030.
The offshore development is also being driven by an investment tax credit set to end in December 2019 and is equal to 12 percent of expenditures. U.S. Sens. Susan Collins (R-Maine) and Tom Carper (D-Del.) have introduced a bill to extend the tax credit for up to eight years.
The Interior Department has held eight competitive lease sales that resulted in 15 offshore wind leases over 1.7 million acres that has the potential for 21 GW of capacity. In February 2022, the Bureau of Ocean Energy Management completed a bidding process that realized $4.37 billion for 488,000 acres across six lease areas in federal waters off New York and New Jersey.
Projects have also been proposed off the Southeast coast, off California and Hawaii, and for the Great Lakes.