Meerwind turbines poised to go in

Installation of the Meerwind offshore wind farm in the German North Sea is on course to be completed by year-end said the company developing the project, as it revealed it spent up to €15m ($19.9m) clearing unexploded bombs from the seabed.

So far 80 monopile foundations and 71 transition pieces have been installed at Meerwind said Jens Assheuer, managing director of WindMW, which is building the 288MW project and will operate it.

The company will start installing the 80 Siemens 3.6MW turbines next week with help of Seajacks’ Zaratan installation vessel, Assheuer said.

Later the Leviathan vessel will also start adding turbines at the wind farm, 23km north of the German island of Helgoland. A substation that bundles the AC power from the plant’s turbines is slated to be put in its location in the fall.

While the wind farm itself will be ready on schedule, however, its grid connection will definitely be delayed,

“We know the grid connection is advancing, but TenneT hasn’t told us when it will be ready,” Assheuer told Recharge. WindMW is owned 80% by US private equity firm Blackstone, while developer Windland Energieerzeugung holds another 20%.

Germany’s Nordic Yard shipyard last year had said it won’t finish construction of the converter platform for the HelWin1 grid link at the end of 2012 as had been previously planned. Asked by Recharge, transmission system operator (TSO) TenneT  today couldn’t immediately say what the new date for its completion will be, but on its website says the grid link project is expected to be ready in 2014.

German offshore wind projects have been plagued by lengthy delays to grid links, in part due to past financing difficulties by TenneT, which is responsible for providing the connections, and project over-runs involving Siemens and other suppliers.

WindMW will temporarily supply the turbines with electricity from diesel generators until the link is ready, as installed units need to be in motion to avoid damage, Assheuer said.

Apart from the grid connection delays, the €1.2bn ($1.6bn) project also had to face explosive challenges lying on the bottom of the sea. WindMW had to pay between €10m and €15m for clearing unexploded weapons, after experts found still-functioning bombs, a mine and hand grenades at the location, Assheuer said.

Some 1.6 million tonnes of weapons from both world wars are still lying on the bottom of the North and Baltic Seas, estimates Heinrich Hirdes, a company specialising in explosive ordnance disposal services.

Allied bombers often dropped unused bombs on the island of Helgoland or the open water when returning to UK bases, while some additional ammunition ended up in the sea for training purposes after the war.