Decentralized ventilation system 2022

Occasion and goal

As part of the Federal Ministry for the Environment’s National Climate Protection Initiative, this project was implemented to improve air quality in school buildings. The goal was to create a healthy indoor environment through the use of modern ventilation technology, enhance students’ ability to concentrate, and at the same time help reduce greenhouse gas emissions.

Concept for air quality in school buildings

Good air quality in schools stands for:

• Greater ability to concentrate
• Higher learning success
• Less strain on health
• Improved workplace quality
• Reduction of heat loss

Implementation status in building management

• Decentralized ventilation units for renovation measures, central units in new builds
• No connection between supply air and extract air
• Separate air routing in the heat recovery system
• Uncontaminated clean supply air is drawn in, contaminated room air is extracted
• Very good air quality, low noise level, efficient technology
• Exterior windows can also be opened

Air Quality Threshold Values from the
Guidelines for Indoor Hygiene in School Buildings, “Federal Environment Agency”

Design
: One
decentralized ventilation unit per classroom with a capacity of 850 m³/h and 85% heat recovery

• In teaching mode 650 m³/h corresponds to 72 % of the nominal volume flow 29 dB(A)
• In pause mode 850 m³/h corresponds to 100% of the nominal volume flow 35dB(A)

Simple CO2 control:
550 ppm ON, 500 ppm OFF, target value: CO2 < 1,000 ppm over 60 minutes;
windows can still be opened

Avoidance of overheating

• Night ventilation if the outside temperature is 4 °C below the room temperature in the period from 01.04 to 30.09, between 3:00 a.m. and 7:00 a.m.

• Intelligent full sun shading, automatic mode daily from 6:00 p.m. to 8:00 a.m., user mode: 8:00 a.m. to 6:00 p.m.

CO2 Measurement
Results: Window Ventilation vs. Mechanical Ventilation Using Decentralized Ventilation Units

Ventilation System at the
Laurensberg School ComplexMechanical Ventilation

• Automatic continuous air exchange depending on the CO2 concentration
• Manual window ventilation still possible

Promotion

The installation of decentralized ventilation units is being promoted as part of this project of the building management of the city of Aachen.

Grant ID: FKZ:
03K13592Duration: March 1, 2020–December 31, 2022Grant
amount: €457,380

www.klimaschutz.de/

www.ptj.de/klimaschutzinitiative-kommunen

Through the National Climate Protection Initiative, the Federal Environment Ministry has been launching and supporting numerous projects since 2008 that help reduce greenhouse gas emissions. Its programs and projects cover a wide range of climate protection activities: from developing long-term strategies to providing concrete assistance and investment support. This diversity ensures a steady stream of good ideas. The National Climate Protection Initiative helps to embed climate protection at the local level. It benefits consumers as well as businesses, municipalities, and educational institutions.