A building for tomorrow and for the future
An interview with Torben Vogelgesang
We are living in a time of uncertainty, but the Elbtower is going to evolve into a building fit for the future. Torben Vogelgesang, Branch Manager at Signa Real Estate Management Germany GmbH in Hamburg, explains in an interview what makes the building project so special.
Mr. Vogelgesang, does it make sense with things as they are today to build a new landmark for Hamburg like the Elbtower?
Sure, these are very turbulent times now, and we’re feeling that with our project too. But we’re not just building for tomorrow, we’re building for the day after tomorrow. We are building the Elbtower to meet the demand for the end of 2025 and that demand is still there: High-quality space, flexible in use, built for the future and operated in a CO2-neutral way. That is what is expected and that’s what the demand is for. Around 50% of the space has already been allocated.
What makes the Elbtower so sustainable?
The project has been designed with sustainability in mind throughout its entire life cycle. That has even started already with the construction. For example, we can save a lot of concrete simply by using clever and technically sophisticated designs. Our prestressed concrete ceilings are not 35 centimeters thick, as is usually the case, but only 25 centimeters. Our hollow core slabs save concrete and weight. And finally, the steel composite columns we use also reduce concrete and at the same time ensure that usable areas can be designed more flexibly.
And regarding the building’s operation: How do you achieve a CO2-neutral building?
We use two energy sources for the Elbtower. One is district heating, because we can access district heating in the eastern part of HafenCity, which is fed by waste heat from the copper manufacturer Aurubis’ production processes.
It is industrial waste heat and so it is certified CO2-neutral. We also use the same source directly in the building to supply the necessary cooling in the tower via absorption chillers. In addition we use the heat in Hamburg’s wastewater. One of the city’s major sewers runs alongside the Elbtower. The water there has a constant temperature throughout the year. We tap into this energy via a large heat exchanger.
The special thing about the Elbtower is that each of these two systems could supply the building autonomously. In terms of redundant supply, we use both systems, the district heating for the base load and the wastewater heat exchanger system for peak loads. In the event of a malfunction of one of the systems, the other system would take over the supply completely.
How do tenants contribute to CO2-neutral operation?
We conclude green lease agreements with our future tenants. Such leases regulate the sustainable use and management of a property. This means that the tenants undertake to purchase sustainable building materials and operating supplies, for example green electricity. For large companies in particular, it is important that the entire building meets current ESG standards.
In doing so, the Elbtower is a good fit for HafenCity…
Right now, all owners and landlords in Hamburg are thinking about the sustainability of their properties. No one can afford to neglect this aspect, and in HafenCity in particular we have a number of examples of sustainable buildings. Sustainable energy supply works very well through cooperation with Enercity and with the connection to district heating. Hamburg supports this politically and is strongly committed to green hydrogen. The goal is for climate-neutral energy to be available at every location.
Now that you have clarified the basics for the Elbtower – financing, the pre-letting quota and handing over the land – construction has begun. What’s next?
If you look at the construction site cam today, you will see the first core walls on the floor slab. Now the shell is growing upwards massively, and at the same time the next sections of the floor slab are being set in concrete – we are currently four weeks ahead of schedule. By the end of the year, the tower will be 70 meters high.
Are you not anticipating any more problems?
With a project of this size, you have to expect a lot of imponderables, starting with the weather. But we have planned for sufficient buffers.
Could the huge cost increases in the construction industry upset the budget?
We have pre-ordered and stored the material we need for the shell in sections.
So the steel has already been there for a long time. In addition, the market for steel has calmed down again. The concrete comes from the Elbtower’s immediate vicinity, and the corresponding quota has been reserved. But the situation in the construction industry has changed fundamentally. Companies are accepting orders again. This naturally eases the situation for us, too – especially because the Elbtower is a major landmark project which everyone wants to be involved in.
What are you personally looking forward to when the Elbtower is finished?
I’m looking forward to when it’s finished because I like to finish buildings – and I also like to finish on budget. But what I’m looking forward the most is the view from the viewing platform over the city and the River Elbe toward the North Sea. So I hope that we also have good weather for that on the first day!