The new school is equipped with KNX, a system ABB for building automation

When students and teachers at Kattegatt high school in Halmstad returned after the summer holidays, it was to a state-of-the-art, newly built school equipped with Sweden’s first brain gym. An automatic control lighting system from ABB helps to make the new school both energy-efficient, safe and comfortable.

“We have been eager to build a school that is at the forefront of technology, both to become an attractive school for the future students and to build a sustainable and smart school of the future that inspires, provides comfort and care and places sustainable wellbeing at the heart of our activities”, says Ida Ahlberg, school superintendent and the one responsible for the school building. The new school, with more than 19,000 square meters and space for 1,600 students plus 200 teachers, is equipped with KNX, a system for building automation. At present, the KNX system controls the lighting throughout the school. All installed luminaires are equipped with DALI, a standardized interface for digital light control, which enables simple and scalable control via KNX. The school also features presence detectors which ensure that the lighting is dimmed and then switched off if the room remains vacant for a while. When the last person leaves the school and sets the alarm, all lighting is automatically turned off helping to preserve energy and reducing light pollution.

“The combination of KNX and DALI is unbeatable in lighting. Calculations show that you save at least 30 percent energy compared to manually controlled lighting. In such large premises, there is always someone who forgets to turn off the lights, so this system provides peace of mind and helps save energy as lights can be turned off in rooms/areas that are not occupied”, says Anders Holmén, sales specialist at ABB Electrification. In the future, there is the opportunity to connect and control more things with the KNX system, such as heating and blinds. In addition to the energy savings and the convenience, the KNX system also contributes to increased safety. If one of the emergency exits fails and is not unlocked when the school alarm is turned off in the morning, the school remains dark – a clear signal that it should not be used. Should the fire alarm set off, the light is regulated up to a maximum throughout the school at the same time as sound and projector in the auditorium are switched off. This facilitates safe and timely evacuation protecting pupils and teachers.

“This is by far the largest KNX system I have ever programmed and commissioned. But it has been great and much faster than I thought, even though I have only worked with KNX for a couple of years. The ABB team were always available when I needed any additional system support set-up or had any questions to help optimize the system”, says Daniel Bengtsson at the company Prenad in Halmstad who installed the system.

For a building the size of Kattegatt high school, an automatic lighting control system means major energy savings. According to the Swedish Energy Agency, lighting accounted for almost a third of electricity consumption in an average Swedish school. With modern LED luminaires in combination with KNX control, it is possible to reduce the electricity consumption for lighting by more than 85 percent compared with older, manually controlled luminaires. At the school it is expected that its energy consumption will decrease significantly; from around 150 kWh per square meter each year in the old school to about 80 kWh per square meter each year in the new one.

FACTS: ABB delivery to the school

• Presence detectors
• KNX / DALI gateway
• Breaking actuators
• Binary inputs
• Universal interface
• Pushbutton sensors
• Wiring accessories, series Jussi and Impressivo

Text: Ingela Roos

Photo: Anna Rehnberg