Off-shore wind energy

Green electricity from the EnBW He Dreiht offshore wind farm

In dialogue

Wednesday, November 15, 2023, 7.30 a.m. Chilehaus, Hamburg
The sun has not risen yet, and Chilehaus, a UNESCO World Heritage building, shines out magnificently in the dark.

Dr.-Ing. Thomas Schrey (PPA Originator at EnBW) and Dr.-Ing. David Gohsen (Head of Portfolio Management Power at Evonik) have scheduled an early-morning meeting in the offshore wind office of energy company EnBW (Energie Baden-Württemberg AG) to discuss the new EnBW He Dreiht offshore wind farm and Evonik’s power purchase agreement (PPA) for green electricity.

Dr. David Gohsen (Evonik) and Dr. Thomas Schrey (EnBW) at EnBW’s offshore office.
View of the prow of the Chilehaus.
Discussing the location of the new EnBW He Dreiht offshore wind farm.

David Gohsen: Hello Thomas, nice to see you. Many thanks for agreeing to today’s meeting in your offshore wind office in Hamburg to talk about our long-term purchase agreement for green electricity.

Thomas Schrey: Hello David, I’m glad to welcome you to our office here in the Chilehaus. The shape of this building is reminiscent of a ship. It’s almost a hundred years old and is a UNESCO World Heritage Site.

David: Originally, it was a symbol of economic upswing. In much the same way, Evonik wants to play a proactive role in shaping and driving forward the energy transition. One particular goal is that, by 2030, all the electricity we source externally should be green. Green energy and the associated reduction in CO2 are central to our sustainable corporate strategy. From 2026, we will be sourcing 150 MW of electric power from the EnBW He Dreiht offshore wind farm. That will meet more than a third of Evonik’s total electricity demand in Europe.
Thomas, perhaps you can give us some more details of the project and the present status.

Thomas: Nomen est omen: He Dreiht is a dialect term for “It Spins”. That’s a really apposite description of EnBW‘s third wind farm! It is being built at a site about 90 kilometers north-west of the island of Borkum and 110 kilometers west of Helgoland. It will have 64 wind turbines in total, with installed capacity of 960 MW and will start to feed electricity into the grid at the end of 2025. As one of the first non-subsidized offshore wind farms, it will almost double EnBW’s offshore portfolio, which generates an output of 976 MW at present.

He Dreiht moves into a completely new dimension compared with our other North Sea wind farms, Hohe See and Albatros, which are already operating. It is also the first commercial project to use the Vestas V236-15 turbines, which have a nominal power of 15 MW each.

So EnBW is continuing its pioneering role in the offshore sector. Moreover, with total installed capacity of 960 MW, EnBW He Dreiht is currently one of the largest projects for Europe’s energy transition. Theoretically, it could supply renewable electricity to 1.1 million households.

With a hub height of 142 meters and a rotor diameter of 236 meters, one rotation covers an area of 43,742 square meters—equivalent to six soccer pitches. The grid operator TenneT TSO will connect the wind farm to the grid via an offshore transformer station and two high-voltage direct current cables. The total cable length will be 230 km, with 120 km offshore and 110 km onshore.

Manufacture of the transition pieces began early in 2023. Work on the monopiles and the cabling has also commenced, and production of the wind turbines started recently as well. From the permitting, financing, and production perspectives, the project is right on schedule. David, could you explain why you decided to take part in our offshore wind tender?

Our goal is to switch our external electrical power sourcing worldwide entirely to green energy by 2030.« Dr.-Ing. David Gohsen (Evonik)
The EnBW He Dreiht project is financed exclusively by the private sector and will be one of Germany’s first non-subsidized wind farms.« Dr.-Ing. Thomas Schrey (EnBW)

David: That’s a great question. The advantages of offshore wind energy are clear: Offshore wind turbines benefit from higher and steadier wind speeds. Therefore, they can generate about twice as much electricity as comparable onshore installations.

That makes them very reliable and ensures even energy generation, so they are an attractive basis for generating power from renewables.

Through our commitment, we want to encourage the installation of further renewable energy assets and drive forward the energy transition. Our agreement secured the financing, so it was possible to start realizing the wind farm. That additionality factor was an important aspect of the EnBW He Dreiht project and our decision to take part in the tender. Thomas, could you explain in detail what these PPAs are and what function they have for Evonik?

Thomas: Of course. Power purchase agreements—or PPAs for short—are long-term supply contracts between suppliers and, generally, large industrial users. Like our joint PPAs, they often run for more than 15 years. The industrial customers source physically green electricity directly from renewable resources via these installations, often on fixed, predefined terms. Perhaps I should say that PPAs are a central element in the energy transition: they help guarantee reliable financing of major projects because they give the operators calculable revenues of cash inflows. The EnBW He Dreiht wind farm is a good example.

The electricity supply agreements we signed with you at a very early stage in the project were the key basis for obtaining the approval of EnBW’s supervisory board for the final investment decisionin the wind park in March 2023. As a result, this purely privately financed project is making progress and EnBW He Dreiht will be one of Germany’s first non- subsidized wind farms.

Chilehaus—a UNESCO World Heritage site

Incidentally, this striking tip is the sharpest angle of any facade in Europe.

The Kontorhaus and warehouse districts and the Chilehaus in Hamburg (Germany) were awarded UNESCO World Heritage status on July 5, 2015.

The Chilehaus is an office building built between 1922 and 1924 in Hamburg’s trading district. The architect, Fritz Höger, was a pioneer of brick expressionism in the 1920s. The Chilehaus covers an area of 5,950 m2 and was one of the first high-rise buildings in Hamburg with up to ten storeys, a gross surface area of 36,000 m², and 2,800 windows. With its eastern tip resembling the prow of a ship, it is an icon of expressionist architecture.

As well as its unique architecture, the building is a symbol of Hamburg’s economic upswing. Over the years, it has become a tourist attraction. It is particularly worthwhile viewing the building’s charming interior features: the linoleum flooring, which is subject to a conservation order, the paneled mahogany doors in the stairwells with their hand- wrought brass handles, and the elaborate decor. For the construction of this building, the merchant Henry Brarens Sloman purchased 4.8 million bricks in 1922.

In the podcast:

Dr.-Ing. Thomas Schrey and Dr.-Ing. David Gohsen in conversation about…
…the Power Purchase Agreements on the purchase of green electricity.

David Gohsen and Thomas Schrey in the podcast

In the video

Dr.-Ing Thomas Schrey and Dr.-Ing. David Gohsen in conversation about…
…the purchase of green electricity from the EnBW He Dreiht offshore wind farm.
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