The building was designed as a low-energy building according to the guidelines of the Energy Efficiency Ordinance. To do so, the engineering firm of TGE, Gelnhausen, a firm known for its energy-optimising building plans and for its open innovative technologies, utilised a pellet heating system and a central fresh air supply system with specially- designed heat-recovery ventilation equipment for each of the various areas being used. The fresh air, with specified air exchange rates of between 7.2 and 9 m³/h m², is not fed directly to the rooms, but first flows through cooling tubes inside the concrete ceiling. While it flows through, the cold supply air heats up to approximately ceiling temperature. This achieves an outlet temperature of about 21°C entirely without a reheater, resulting in an overall heat recovery of more than 95 %. Through appropriate climatic specifications, and with the potential of free cooling, favourable operating costs and energy savings are achieved which would otherwise not be possible. By reclaiming energy from the concrete ceiling, an optimum thermal comfort is achieved for the building.
Object: | Grimmelshausen Gymnasium, Gelnhausen |
Architect: | hkr.architekten, Gelnhausen |
Proprietor authority: | Schulträger Main-Kinzig-Kreis |
Planning office: | Ingenieurbüro TGE, Gelnhausen |
Scope: | Planning of the heating, ventilation and sanitary facilities: |
Air flow rate for Concretcool only Cafeteria in the basement: 3.000 m³/h | |
Library and foyer on the main floor: 3.200 m³/h | |
Multifunction rooms on the main floor: 1.250 m³/h | |
Technical data: | Pellet heating system, 150 kW for floor heating, radiators and the building ventilation system |
total air flow 18.400 m³/h in 5 air conditioning sections with heat recovery (cross-flow heat exchange) | |
48 kW chiller, air-cooled | |
Measurement and control system by Sauter | |
Heating, ventilation and sanitation system costs: | 650.000 Euro |
Gymnasium College Grimmelshausen ↓
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In contrast to conventional systems, the supply air is not fed directly to the room, but first flows through aluminium cooling tubes embedded in the ceiling. The supply air cools the ceiling in the process. At the same time, the heat recovered is used to heat the supply air.
Kiefer Klimatechnik GmbH is a leading company in the field of ventilation, air handling and air conditioning technology. Our range of services includes consulting, planning and execution of systems for thermal comfort and industrial air conditioning, as well as the associated installation and maintenance. For almost four decades, Kiefer has also been selling high grade ventilation components worldwide, such as linear diffusers, wall passages, displacement outlets, light and acoustic sails, chilled ceiling panels and concrete core cooling systems, developed in the company's own laboratories.
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