.

News – What`s happening in energy research

read short description
subscribe News

The entrance side of the renovated Uhland School: Clearly visible are the weather- and burglar-proof window frames which can be opened automatically at night if required.
© Micaela Münter, BINE Informationsdienst
School refurbishment
26.10.2016

View of the façade: Photovoltaic modules are situated beneath the windows.
© Micaela Münter, BINE Informationsdienst

View inside a chemistry classroom: The outflow vents for the ventilation system are situated in the rear wall.
© Micaela Münter, BINE Informationsdienst

View inside the heating plant room with heat pumps and the buffer storage system
© Micaela Münter, BINE Informationsdienst

Learning and working in an energy-plus school

Uhland School in Stuttgart, which dates back to the 1950s, no longer accorded with today's structural and energetic standards. The renovation work is now almost complete and the City of Stuttgart is getting its first energy-plus school. A photovoltaic system on the roof and façade of the building covers the electricity requirement. Borehole heat exchangers provide the heat for the heat pumps that heat the school. The school will move back into the renovated rooms at the beginning of next year. A two-year scientific monitoring programme will then begin.

The primary and technical secondary school in Stuttgart has several buildings. The complex includes the main building, built in 1954, a pavilion with cafeteria, an extension building built in 2004 and a gym. For cost reasons, it was decided not to renovate the gym and pavilion but to replace them with new buildings over the coming years. The extension was given a new glass roof as the old roof was leaking. No further refurbishment measures were necessary. The project therefore focussed on renovating the main building with a usable area of 1,200 square metres. The average annual heat consumption before the renovation was about 154 kilowatt hours per square metre per year and is intended to fall to 39 kilowatt hours after the renovation.

Refurbished into an energy-plus school

Covering a total area of 1,500 square metres, photovoltaic modules on the roof and façade of Uhland School produce the electricity required for the heat pumps, lighting and ventilation systems, auxiliary power and computers. Other photovoltaic modules with a 200-square-metre surface area were installed on ancillary buildings. This surface area was necessary since all classrooms have been equipped with electronic whiteboards, which are increasingly replacing school blackboards. The digital panels, which are connected to computers, require additional power and are a further source of heat in the classrooms.

To achieve the energy-plus standard when renovating buildings requires excellent insulation for the building envelope as well as efficient and electricity-saving building technology. The insulation consists of a thermal insulation composite system made of expanded polystyrene (EPS). Floor slabs abutting the ground, parts of the roof as well as gabled walls are insulated with four centimetre-thick vacuum panels. Together with the tripled-glazed windows, the average U-value of the building envelope amounts to 0.23 watts per square metre and Kelvin.

Hidden building technology

The students and teachers will hardly notice the plant engineering. The ventilation technology is concealed in the window frames, and sensors for the air quality and motion detectors for the lighting are hardly visible in the acoustic ceiling. The presence-controlled lighting can also be switched off using light switches. To ensure that the students do not forget to turn off the lights, the client decided to use light switches installed by the door to each classroom. Teachers can access the control system at any time and change the ventilation and lighting.

During the heating period, decentralised ventilation units with heat recovery supply the classrooms with fresh air. The CO2 concentration determines the volume flow of the fans. In summer the system is switched off and ventilation is provided by the windows. To ensure that it does not become too warm in the school, external louvres with daylight control protect against too much solar irradiation. If the indoor temperature rises above 22 degrees Celsius, cool air flows through the school during the night hours. This is achieved via burglar- and weather-proof windows that open automatically.

Move back in and scientific monitoring

Lessons will begin in the new premises in January 2017.  "The pupils are already very much looking forward to the new building and all classes would like to move there," reports Headmistress Beate Anderka. In addition to well-regulated building technology, the users will also play a very significant role if the school's energy concept is to be successful in practice. For this reason, the roughly 460 pupils and 40 teachers will be given a detailed introductory briefing about the building and its technology.

A two-year scientific monitoring programme will start once they have moved in. This is intended to support the commissioning, evaluate the energy concept, identify energy efficiency weaknesses and investigate the comfort. In addition to the measurement data from the building, a weather station on the roof of the school will record the external climate. Initial results are expected at the end of 2017.

(mm)

notepad

BINE subscription

Subscribe to newsletter

Addresses

Project management
Landeshauptstadt Stuttgart

Conception and monitoring of the planning and execution phase
Fraunhofer IBP

Info tips

Ventilation in schools
BINE-Themeninfo I/2015

Net Zero Energy and Net Energy Plus Buildings
BINE-Themeninfo II/2015

Links

Project summary
Further information on the project at EnOB.info

EnOB research initiative
Projects, reports, news and analysis from the energy-optimised construction research field