(Repeats to additional subscriber service)
* Two TenneT-led line projects delayed to 2025
* Underground cables cost several billion euros more
* Consumers must pay for grid investments
* Without new lines, technical risks unmanageable
By Vera Eckert
BERLIN, June 8 (Reuters) - Germany’s biggest grid operator has delayed major north-south power lines by three years and warned they will cost more than forecast, but said there is no alternative if a shift to renewable energy is to succeed.
Dutch group TenneT has put back the completion date for the SuedLink and SuedOstlink projects to 2025, Urban Keussen, chairman of the board of TenneT GmbH, its German arm, said.
The transmission lines will bring wind power from the north of Germany to the industrialised south, where nuclear plants are being shut down, to help Berlin meet a 40 to 45 percent renewable power share by 2025 to help fight climate change.
“The reason is that major parts of the connections must be put underground,” Keussen said in an interview.
“Costs of SuedLink are now around 10 billion euros ($11.4 billion) instead of originally 3 to 4 billion, and those of SuedOstLink, originally estimated at 1 billion, will rise pro rata by the same multiple,” he added.
A law passed in 2015 required that the lines go underground to quell opposition from local residents to pylons.
TenneT redrew its plans to comply with the change, which apart from causing delays also boosted costs.
German energy laws require grid companies to provide network stability and to charge consumers for the service via their final bills. Transmission line investments are written off over 40 years.
SuedLink is to run from Hamburg, near wind installations in the north. to Bavaria, close to where the Grafenrheinfeld reactor closed last year, ending stable round-the-clock power.
SuedOstLink will run from eastern Saxony-Anhalt to Bavaria, where the Isar 2 reactor is due to shut in 2022.
Until the lines are ready, the costs of scaling down excess wind power and activating reserve plants in the south will escalate, Keussen added.
Meanwhile, intervening in plant schedules cost 1 billion euros last year and this bill could rise to 4 billion euros per annum by 2022/23, Germany’s energy regulator estimates.
The cost of emergency measures would ultimately outstrip those for new lines if they did not materialise, said Keussen.
“It does not make sense to invest in wind power, get no electricity, and to pay on top of that,” he said.
TenneT owns 40 percent of the German onshore grid and is in charge of linking up future offshore North Sea wind parks. ($1 = 0.8770 euros) (Editing by Alexander Smith)