Sustainability

Clean thermal energy for a new part of town

Low CO2 emissions thanks to overlapping solutions: HafenCity’s energy concept makes use of all potential savings; remote and local district heating sources - e.g. from decentralized geothermal or solar thermal plants - complement each other for an effective energy mix

Photo shows the fuel cell at Großen Grasbrook

Energy supplier Vattenfall is testing a fuel-cell in a pilot project, one of various leading-edge technologies used in HafenCity (© Vattenfall)

Supply of thermal energy in HafenCity is safeguarded through a mix of concepts that are both innovative and sustainable. Residential buildings are not simply supplied with remote district heating, heating generated locally (produced for example by decentralized combined heat and power units, fuel cells or solar plants) completes the energy mix. For air conditioning purposes, heat pumps or geothermal energy are also gaining popularity. One important incentive promoting solutions of this kind is the HafenCity Ecolabel, introduced in 2007.

After a tendering process throughout Europe for the supply of heating to western HafenCity, a contract was awarded back in 2003. A CO2 baseline limit of 175 g per kilowatt hour was a condition for the contract, although the choice of technical solution for achieving that target was left up to bidders. Compared with gas-fired heating systems supplying individual buildings, a 27 per cent reduction in emissions can be achieved.

Heat supply for HafenCity’s eastern section will see CO2 emission limits reduced even more significantly to just 89 g/kWh. After tenders had been invited from all over Europe, Dalkia Energie won the contract in 2009; the energy services supplier clearly undercut the 125 g/kWh emission limit threshold set for the tender.

Its concept is for a local energy supply network, fed by various power units both within and outside HafenCity. A woody biomass-fired combuster, a biomethane fuel cell and a heat pump – almost all renewable energy sources – will be deployed. Because of its decentralized structure, the system can grow with the new neighborhood. Flexibility was a crucial factor in this tender: since development of HafenCity will continue into the 2020s, future demand cannot be accurately estimated at this stage.

Other innovative solutions for power supply are being explored by various research and future projects in HafenCity. On Grosser Grasbrook, for example, tests are being carried out to discover whether geothermal energy can dehumidify room air. A fuel cell is being tried out in a pilot project in the central heating plant on Grosser Grasbrook. In spring 2012, a filling station for the growing hydrogen-powered bus fleet operated by Hamburger Hochbahn, was commissioned near Oberbaum bridge, the main entrance to HafenCity.