ConcretCool
Concrete structures have a high storage capacity. The integrated system (concrete core cooling with supply air) utilizes the potential for free cooling. This leads to more efficient systems and energy savings previously unobtainable with typical air based solutions. Neutral studies and test results on the first construction projects completed confirm this ecologically and economically innovative concept.
System Description
The ConcretCool system combines fabric thermal storage with the ventilation air supply. It is particularly cost effective where specific ventilation rates are required due to either standards or constraints of the building site.
Internally finned aluminium tubes transport the conditioned outdoor air through the concrete slab to the various room.
The system is charges the slab overnight and then operates during the day to provide ventilation and additional cooling.
Ventilation air is supplied to the space either via ceiling mounted swirl diffusers or displacement ventilation.
Installation
The structural steel and piping require preliminary coordination. The thickness of the joist-free, flat concrete ceilings is approx. 25 to 30 cm. The system can be integrated without problems and without changing the dimensioning required for the static loading. The cooling tubes are laid in-situ in the concrete, and are fully integrated with the re-bar installation. The finished ceiling is capable of storing 165 to 200 Wh/m²K of heat depending on the thickness and concrete quality. With this effective storage capacity, operative temperature peaks are reduced and the heat load distributed uniformly.
Exact Cooling Capacity
Studies and measurements show that the system typically dissipates a cooling load of 40 to 60 W/m² with the outer air required for hygienic reasons only. Even a peak load of 80W/m² can be compensated without approaching the limit curve in DIN 1946/2.
Thermal Comfort
Displacement combined with cooling ceilings ensures optimum thermal comfort. The systems are superior in this point because a high percentage of the heat is dissipated by radiation. This is experienced as extremely pleasant. Drafts, such as occur with convective load dissipation, are eliminated.
Reliability
Installation of air tubes in the concrete ceiling offers an alternative to clients who have objections to the installation of water pipe work in the ceilings. Leakage is excluded. If a tube is drilled into unintentionally, the damage can be corrected easily.
User Acceptance
Only outdoor air is conditioned and the dimensioning is accomplished according to the hygienic requirements. No recirculation air is used. Ventilation is accomplished in the form of low impulse displacement air. A room is cooled to 80% by the room surface without draft and is optimally adapted to the ergonomic requirements.
Even a peak load of 80 W/m² can be compensated without approaching the limit curve specified in DIN 1946.
The humidity is limited to ensure optimum air quality. The system guarantees:
- Optimum thermal comfort
- Better air quality
- Higher user acceptance
Energy consumption
Concrete core cooling with supply air is a highly efficient, energy saving process.
The temperature of the displacement air of approx. 21°C is achieved without requiring any primary energy. Free cooling also allows highly effective night cooling when required. In combination with the extremely low energy consumption, this system achieves exceptionally good cost/benefit ratio. This system represents a leap in the development of ecologically and economically practical energy savings.
Air based systems are ideally complimented by energy recovery air handling plant including desiccant systems and geothermal cooling and heating.
Installations
Over a million square feet of CONCRETCOOL systems have been installed and are operating successfully.
