In the present communication, a psychometric model has been presented to evaluate the performance of rotary desiccant wheels based on different kind of desiccants e.g. silica gel and LiCl. The developed psychometric model is based on simple correlations between the relative humidity and enthalpy of supply and regeneration air streams. The model is used to predict the performance of three type of desiccant rotors (Type-I, II and III). The model is tested corresponding to a wide range of measurement data.

The combination of an open wet cooling tower with chilled ceilings is a CFC free, cheap and low energy cooling solution. The efficiency of this alternative to mechanical cooling is very dependent on climate. There is a need for specific tools to help designers to size the system and to estimate its energy and water consumption. A building simulation tool, called ConsoClim, has been used to predict the performance of this system for different French climatic locations, thermal inertia, internal loads and solar gains.

To evaluate innovations and efficiency as regards air-conditioning, it is necessary to know for how long and in which conditions the equipment functions, an indication related with the COOLING LOAD and which is their effectiveness - EER - on average (or Seasonal) known as SEER. We extended the concept of SEER to include all sources of electricity consumption, namely the secondary equipment, and we called this extended concept the SYSTEM SEER.

This paper presents the results of a field study on five HVAC duct systems in France. The principal objectives of this work were a) to evaluate the extent of duct leakage in those systems; b) to compare design and actual fan flow rates; c) to evaluate the thermal energy losses in the air ducts. The ductwork airtightness, measured by fan pressurisation method, was found to be in general well above the leakiest EUROVENT 2/2 class (class A), yielding unacceptable uncontrolled airflows. Fan airflow rates were measured with the constant injection tracer gas method.

In order to save energy for building cooling during hot days in regions with cool nights, air circulation throughout the interior of the building has been envisaged as a means to lower the temperature of the building structural mass. In this way, energy required for cooling the building interior is reduced, due to lowered temperature of the wall, ceiling and other structural elements mass, and a greater storage of heat resulting from various heat gains the following day when air-conditioning is on.

In this paper, a literature survey on rectangular and round ventilation ducts is presented. The comparison is based on two important aspects: pressure drop and noise radiation. The pressure losses in the ductwork should be kept as low as possible without jeopardizing proper control of the flow rates in the system. Pressure loss through a rectangular duct is significant higher than a volumetrically equal round one. The higher the aspect ratio, the higher-pressure loss in the rectangular system.

The Solar-Campus Juelich consists of two buildings, as part of the University of Applied Sciences, Aachen, and student dormitories for 136 students (5 row houses), see Figure 1. In a general agreement, the overall energy demand for space heating of all buildings was limited to 40 kWh/m 2 a, which is less than 50% of the existing German national regulation (Wrmeschutzverordnung 1995). Extra costs were provided through the AG Solar of the German state North-Rhine-Westfalia.

A condensing device allows to avoid condensation on cooling ceilings in rooms with humid air. It uses thermoelectric modules in contact with the cooling panels. The pumped heat is transferred into the cooling ceiling to keep its temperature above the dew point. Tests have been performed in a full-scale chamber. A set of condensing units was mounted on a standard hydraulic cooling ceiling. The control of temperature is achieved by regulating the mass flow of the water. By this method the loss of efficiency of the cooling panels is fully compensated.

In conventional construction, the ventilation air enters a building through a combination of ‘desired’ pathways, via opened apertures, such as a window, vents, and ‘undesired’ pathways, via cracks such as around external openings, joints between building

Detailed simulation studies on the design and development of PV/T systems are being carried out at the Politecnico di Milano, for their possible integration with a sloped roof. Subsequently, a proto-type PV/T air heating collector has designed, manufactured and tested at the experimental site Parco Lambro in Milan in collaboration with a private industry. Thermal and electric efficiencies have been assessed during several days of experimentation.