The new Central Building of Leuphana University represents an exemplary sustainable campus. It is part of the "Climate-neutral campus" project, which was nominated for the German sustainability award. The building concept and design started from an idea elaborated from a group of students within a university seminar with the architect Daniel Libeskind.
One of the key points of the design was devoted to the energy use, with the driver of reducing both costs and emissions which in modern buildings is needed first of all for lighting, ventilation and cooling.
Strategy for reducing lighting consumption: maximization of daylighting through courtyards, light shafts, skylights and transparent door elements let. This is coupled with energy-efficient LED floor lamps in the offices that are controlled based on presence and daylight, as are the circulation spaces and seminar rooms.
Strategies for reducing cooling loads: A rear-ventilated façade inclined towards the sun provides natural shading and passive cooling. All parts of the building are aligned in such a way that none of the outer walls exposes directly to the South. The combination with switchable glazing reduces the summer loads and, thanks to this feature, the installation of a cooling system has been avoided. Moreover, the involvement of the users is enhanced through an interactive interface that accesses building functions via smartphones and PCs, while offering feedback on energy consumption and proper ventilation.
Strategy to reduce ventilation consumption: CO2 sensors were installed throughout the building, even in non-mechanically ventilated areas to reduce heat losses through window opening. The system is first being tested in model rooms with different presence detection systems, and the air quality signal advices the users to open the window when is necessary.
A special focus has been devoted to the design of the low-temperature energy system with water thermal storage. Heat storage benefits directly from the low-exergy heating systems, with a combined heat power system, of the central building, which has a supply temperature of 58 °C, and which uses - internally cascaded - approximately one third of the heat output at a temperature level of 35/25 °C.
Renewable resources provide energy for other purposes throughout the entire campus. Heating is provided by a biogas Combined Heat and Power plant and a solar system of around 720 kWp installed on campus buildings produces additional power, which covers 25 % of the overall energy demand.
Main energy figures:
- Heating Energy Demand: 57.5 kWh/m2 year
- Cooling Energy Demand: 2.6 kWh/ m2 year
- Lighting: 4.0 kWh/ m2 year
- Ventilation: 13.5 kWh/ m2 year
- Emissions: 208.0 t CO2-Eq./year
For more information about the building, visit this website.