Sustainability
In various areas HafenCity is making big contributions to sustainability
Halting global warming, protecting biodiversity and tackling a host of other ecological challenges will only succeed if households and companies are in a position to shape lifestyles and commercial patterns in a sustainable way by creating suitable economic parameters and appropriate infrastructure. The development of cities is of particular importance in this context, as 77 percent of the population living in Germany is concentrated in conurbations. Since a large part of our cities has already been built and the existing stock can only adapt gradually, the importance of neighborhoods that are at the planning stage or under construction is that much higher.
It is not only urban development and infrastructure that contribute to the sustainability of HafenCity, but also each individual building. The financial amount of approximately €10 billion invested by developers alone, as opposed to approximately €3 billion spent by the public sector, demonstrates the crucial importance of the properties being built in terms of the ecological quality of the district, but also its social and cultural quality. Since an intelligent, advance purchase strategy for existing properties meant most of the land in the HafenCity area was owned by the city at the start of development, it has since been possible to use the allocation of land to developers as a central control mechanism via the process for awarding planning options and via concept tenders. This approach provides, among other things, for high architectural quality in HafenCity, street level space for retail and cultural uses, diversified housing offers with price differentiation, communal areas and the financial burden of neighborhood management. The focus will thus be on environmental sustainability aspects. These include the high building standard of the HafenCity Ecolabel and pilot projects going beyond it, a smart mobility concept and sustainable heating supply.
Sustainable building
The buildings certified with the HafenCity Ecolabel are models and pioneers of the transformation to sustainable building. They are setting standards and today are already providing answers to important future issues. The sustainable buildings have, for example, lower operating and maintenance costs due to their high energy efficiency and thus offer advantages when it comes to renting and selling. Certification makes these advantages visible for all players, i.e. owners, tenants and users.
Since 2007, HafenCity Hamburg GmbH has been awarding an independent certificate for sustainable building, the HafenCity Ecolabel. Certification was made a condition for the award of planning options on building plots in 2010, and since 2017, with Version 3.0 of the Ecolabel, the highest platinum standard has been obligatory for all new buildings in HafenCity. Thus HafenCity Hamburg GmbH was a very early supporter of the development of innovative, climate-friendly building solutions. Hence it has played a key role in anchoring sustainability ideas in the real estate industry and raising sustainability standards to an ever-higher level.
The most important goal of the mandatory sustainability certification is the reduction of CO2 consumption in the production, operation and deconstruction of the buildings. In addition, health and comfort in and around the buildings play a role, as does the use of natural resources in the environment. The sustainability requirements have also been continuously updated since the last revision of the Ecolabel in 2017. In HafenCity’s newest Elbbrücken and Strandkai neighborhoods, buildings are increasingly being constructed that will take the lifecycle assessment of CO2 emissions well beyond the level of platinum certification. In particular, the aim is to reduce the so-called gray energy. This gray energy, necessary for the construction of a building, includes the energies expended for material extraction, the manufacture of components, the transport of machines, components and materials to the construction site, and the incorporation of components.
Buildings are being constructed from wood, from a mixture of wood and concrete, and with concrete-saving building methods. Renewable raw materials, recycled building materials and CO2-reduced steel are being used. Due to the documentation of the materials used and their separability during deconstruction, the materials of the new buildings themselves will also be recyclable. HafenCity Hamburg GmbH is itself constructing a zero-emissions headquarters building that will have zero CO2 emissions over its life cycle. These projects play an absolutely pioneering role in terms of a comprehensive understanding of sustainability, spurred on in part by the sustainability efforts of HafenCity Hamburg GmbH.
In terms of indicators and verification methods, the HafenCity Ecolabel is similar to the successful certification system of the German Sustainable Building Council (DGNB), founded in 2007, of which HafenCity Hamburg GmbH is a founding member. The DGNB certificate also assesses the sustainability of buildings over their entire life cycle.
Given the high standards achieved by the DGNB certificate, the extensive links with national and international funding environments, and the established sustainability criteria on European capital markets, maintaining an ecolabel limited to a local market is less and less viable, despite its effectiveness in the past. The German Sustainable Building Council (DGNB) and HafenCity Hamburg GmbH are therefore cooperating on the development of a joint certificate based entirely on the established DGNB system.
The new certification is based on a special configuration of the criteria of the established DGNB catalog of criteria in the upcoming 2023 version and is tailored to the special requirements of the HafenCity, Billebogen, Grasbrook and Science City Hamburg Bahrenfeld development areas. Key elements of the previous HafenCity Ecolabel will be incorporated and further developed.
In future, building owners and developers will receive an internationally recognized, ambitious sustainability certificate tailored to the inner-city environment of the four urban development projects in Hamburg. The cooperation between the DGNB and HafenCity Hamburg GmbH will enable the course of transformation followed with the previous HafenCity Ecolabel to be successfully continued.
With the publication of the new joint certificate by HafenCity Hamburg GmbH and the DGNB in spring 2023, the HafenCity Ecolabel will be replaced in its current form as an independent and separate sustainability certification system. From then on, the HafenCity Ecolabel will only be continued in connection with existing contracts, in order to provide continuity for developers.
Green heating power
So that the high energy requirements for the buildings can also be met in terms of infrastructure, all the buildings in HafenCity must be connected to two district heating networks operated by private network operators. In western HafenCity, this is the Hamburg district heating network operated by Vattenfall, which is supplemented in HafenCity by solar thermal power (1,800 m² of solar thermal systems are installed on rooftops in western neighborhoods, providing 40 percent of hot water requirements there), as well as other CO2-reducing generating plants (such as the steam turbine in the HafenCity heating plant). Since 2002, this has enabled an efficient energy mix that, with CO2 emissions of 175 g/kWh, clearly outperforms the conventional environmental standards-compliant natural gas-based heat supply whose CO2 emissions average 240 g/kWh.
Thanks to its decentral, modular local heating supply network, eastern HafenCity can boast contractually guaranteed CO2 emission rates of only 70 g/kWh. Actual CO2 emission rates are considerably lower, at approx. 35 g/kWh under current plans. The concept is characterized largely by the use of emission-free industrial waste heat and renewable energy. The proportion of waste heat in consumption is around 90%. A modern combined heat and power plant in Oberhafen, operated with balanced biomethane, covers part of the remaining heat demand in efficient cogeneration - only the peak load is generated by conventional gas-fired boilers. Industrial waste heat comes from the nearby Aurubis copper refinery, where excess heat from gas scrubbing is now no longer discharged unused into the Elbe. A further energy center at Peute with buffer storage tanks and boilers ensures that the highly fluctuating waste heat can be drawn down evenly and securely. The primary energy factor is 0.17. In eastern HafenCity alone, this will save around 12,000 metric tons of CO2 per year compared with a natural gas-based heat supply when complete.
Smart mobility
HafenCity’s mobility concept prioritizes walking, cycling and public transport (subway, rapid transit, buses and ferries) not only for ecological reasons but also to enhance the quality of the urban environment. This also includes the goal of substantially reducing car ownership in HafenCity. Firstly, this will reduce the construction costs of large underground garages and the need for parking spaces in public areas. Secondly, people who for various reasons are dependent on a car and own one will then use it for the vast majority of journeys. Since owning a private car entails high fixed costs, the distances traveled in the city do not have a significant cost impact. The purchase of a ticket, on the other hand, is perceived as an additional cost.
The smart mobility concept for eastern HafenCity therefore aims to enable residents and workers to dispense with a private vehicle and weigh up the options of cycling, public transport and car sharing according to the situation. In the underground garages of the private buildings, a cross-district station-based car sharing system is being set up as a dependable service for all residents and workers under the terms of the individual property purchase agreements. The system contributes to reducing both moving and stationary car traffic as well as improving the amenity value of public areas through reducing CO2 emissions and noise pollution.