THE SCHOOL THAT REDUCED ENERGY CONSUMPTION FROM 190 TO 54 KWH/M²
Norregård School in Växjö has achieved significant energy savings, reducing consumption from 190 to 54 kWh/m² with demand-controlled ventilation. Through proper insulation and a modern, innovative ventilation system, the renovated school now operates at just 54 kWh per m² per year—26 kWh below the original target.
A Comprehensive Approach to Energy Efficiency
The renovation began when the school’s kitchen was deemed unfit for use, leading to a full-scale review of the building. Originally built in 1974, the school received new windows, improved insulation, and an advanced ventilation system.
We took a holistic approach—essentially, only the outer walls remained. Energy and ventilation considerations became a key part of the planning process.
Following an energy audit, the goal was set to reduce energy consumption to 80 kWh/m² per year. To ensure airtight construction, the windows and wall modules were tested in pressurized chambers, optimizing the installation method.
Ventilation – The Key to Energy Savings
Ventilation played a crucial role in creating an energy-efficient and healthy indoor environment. Lindinvent’s demand-controlled system, featuring active air diffusers and exhaust air recovery, was selected. Each unit independently measures and adjusts its airflow to optimize efficiency.
– We chose a system where each diffuser measures its own airflow. To accommodate the ventilation ducts, an additional floor was built, which actually reduced overall costs as excess heat allowed us to decrease insulation thickness, says Birgersson.
Full Control with LINDINSPECT®
With LINDINSPECT®, ventilation can be monitored and adjusted in real time. The system automatically adapts to occupancy, temperature, and CO₂ levels but can also be fine-tuned as needed.
– The system is easy to control. Occasionally, we’ve adjusted thresholds, for example, in classrooms with fewer students, but overall, it has worked seamlessly, says Birgersson.
ENERGY GOAL EXCEEDED!
At the school’s reopening in 2013, measurements showed that energy consumption had dropped to just 54 kWh/m² per year—far below the initial target of 80 kWh.
Surpassing our goal was due to two key factors: our method of ensuring airtight walls and windows, and the demand-controlled ventilation system. The system creates an excellent indoor climate, maintaining the correct airflow year-round while allowing us to keep the supply air temperature as low as 15 degrees for most of the year.
