DEVELOPMENT OF A PCM AIR FILTER AND ITS APPLICATION TO A CONSTANT The authors have developed a PCM air filter which stabilizes the temperature of air passing though it. This PCM filter has great potential for applications that require a constant temperature air supply. In addition, it can simplify temperature control systems and can contribute to energy conservation. The material in the filter consists of sponge fibers coated with paraffin followed by a coating of resin to prevent leakage and vaporization of the paraffin.

In summer, most areas in Japan are hot and humid. Hokkaido Island, which is the most northern part of Japan, is the only exception. However, air conditioning systems have become the norm in all big buildings in Japan, even in Hokkaido, due to increased internal generation of heat from lights and equipment such as computers and printers. However, the outside air temperature often drops below 26C during summer everywhere in Japan even when cooling and air conditioning is turned on.

The authors have proposed a system for stabilizing air temperature using direct heat exchange between granulated phase change materials (PCM) and air. This paper describes experiments in which air whose temperature is periodically changed to simulate changes of outdoor air temperature is passed through a bed of granulated PCM. These experiments demonstrate that output air temperature is stabilized and remains within the phase change temperature range. Results calculated by a computer simulation program described in a previous paper duplicate the experimental results.

Using performance characteristics of balanced ventilation units tested in laboratory of CETIAT, a complete ventilation system in an individual house is modelised, in details. Simulations are made with TRNSYS program and hourly dynamic calculations on the heating season, on different French climates (three) and different ventilation configurations (five) : high efficiency or classical balanced system inside the attic or inside the heated volume and simple exhaust ventilation system.

The CEN TC 156 / WG2 (ventilation for residential buildings) has prepared a new European draft for the test method of Heat Recovery Units (prEN 13141-7). This method should ensure a common way of testing these units all over Europe. In order to determine if the draft procedure is sufficient enough, both VTT and CETIAT has proceeded to some tests according to the new European standard on the same unit. Results on this first intercomparison give interesting data on the test method applied.

In low energy dwellings the ventilation heat losses are significant. Reduction of these heat losses can be achieved by introducing demand controlled ventilation i.e. ventilation rates are set below normal level when rooms are no longer occupied. This paper outlines preliminary results on energy conservation and health effects in relation to demand controlled ventilation in a low-energy house.

This paper shows that it is possible to calculate the optimal outdoor air rate at different outdoor temperatures in the economiser cycle. The price of heat must increase 3 times before the optimal outdoor air rate during heating gets lower than during cooling. The optimal outdoor air rate during heating is determined primarily by the price of heat. The optimal outdoor air rate during cooling is determined primarily by the price of cooling capacity.

This paper shows that well proved state-of-the-art technology can be utilized to keep annual average energy consumption in office buildings below 130 kWh/m2, which is well below today's average, without compromising any major functional or architectural concepts of modern design. The Norwegian building regulations, which were revised in 1997, demand calculation of energy consumption for new buildings. However, the minimum requirements to energy consumption can even be satisfied with a modest degree of insulation or high internal loads.

Even in cold climates, offices normally need to be cooled due to the internal heat loads from people, equipment and lighting. Either a chilled ceiling or chilled beams with cooled water as medium or chilled air can be used. In the case with chilled ceiling or chilled beams, a constant air volume system (CAV) is used. In the case of air only, a variable air volume (VAV) system must be used. This paper presents the advantages of the two methods of cooling with respect to energy use, which was calculated from climate data.

Even though simulation is being increasingly used in design of modern buildings, the full potential of simulation is usually not achieved. To improve building and HVAC system performance, designers usually guess different values of design parameters and then redo the simulation without actual knowing if the guessed value will lead to improvement. This is inefficient and labor intensive. In addition, if the number of design parameters being varied exceeds two or three, the designer can be overwhelmed in trying to understand the nonlinear interactions of the parameters.