The U.S. Environmental Protection Agency (EPA) in partnership with the NationalAssociation of Energy Service Companies (NAESCO) is demonstrating an approach whichintegrates indoor air quality (IAQ) improvements into energy efficiency upgrades provided toschools using performance contracts. Capital costs of energy-related improvements arefinanced, then repaid from utility and maintenance savings realized as a result of newequipment, systems, and controls. In five public schools in various climate zones across theU.
The Netherlands Agency for Energy and the Environment(NOVEM) is conducting a program for the implementation of Low Temperature Heating (LTH) systems in buildings. The primary goal is to enable the use of Low Talued Energy as a heating source. Major savings in enery consumption can be realised by fully utilising the potential of Low Valued Enery. Besides the argument of savings in energy supply, there are additiond benefits in the fields of. Indoor Air Quality (particles, mites, lower air temperature, annoyance and dust);.
The energy saving practice of stopping ventilation systems at night may reduce the daytimeair quality. Sorption phenomena where pollutants absorbed at night are reemitted during theday and the general slower removal of pollutants at the reduced average ventilation rates willcontribute to the deterioration of air quality at intermittent running systems. The purpose ofthe study was to investigate the impact on construction product emission during the day fromreduced ventilation rates at night. Experiments were performed in three small-scale chambersof Climpaq type with dilution systems.
Air flow patterns and temperature distribution within courtyard have been studied. Wind and thermally driven flow have been thoroughly analysed as a function of the depth to width ratio (Aspect ratio) as main parameter. CFD results show a quite similar behaviour regarding to velocity profiles for all the cases, though temperature profiles are highly affected by dimensions of the courtyard. The whole study can be extrapolated to urban canyons, where air flow patterns are quite similar as a result of having the same geometry.
This paper describes a European project to produce comprehensive design guidance on urban layout to ensure good access to solar gain, daylighting and passive cooling. The project involves:
Since reduction of ventilation rates in dwellings for economical reasons, it has been necessary to study whether this reduction had not been done to the detriment of indoor air quality. Several means of investigating were developed: experimental tests are indispensable but usually expensive that is why numerous research centres choose to model the thermoconvective fields in rooms.
The use of tracer gas is of great help in measuring airflow rates and detecting shortcuts in air handling units, and is essential for ventilation efficiency measurement. However, the planning of experiments, that is choosing tracer gas injection locations and air sampling locations, is not straightforward. Moreover, the mathematics used for interpretation are quite complex, and require elaborate calculations. Therefore, a measurement protocol and the corresponding interpretation algorithms are being developed and implemented in a user-friendly computer program.
In designing thermal and ventilation systems in buildings, an examining process of exchange between the designers and analysts is needed. This study aims to expand the simulation system of thermal and ventilation into an automated process for the design of optimum thermal and ventilative conditions, based on the expertise of analysts, the analysis of the thermal environment and the modification of the design, by automating these functions.
Since the beginning of this decade, natural ventilation in office buildings is receiving specific interest. There are two sorts of application. Natural ventilation can be a strategy for indoor air quality control. Besides it can be used as night ventilation during warm or hot periods. In this case the objective is to cool down the thermal mass and improve the thermal summer comfort. The EC JOULE NatVent project wanted to identify the barriers to the application of natural ventilation in office-type buildings in moderate and cold climates and to provide solutions.
Ventilation is essential for the maintenance of good indoor air quality, although there is evidence to suggest that energy loss through uncontrolled or unnecessary air infiltration is excessive. In this study, estimates are presented for air change (ventilation and infiltration) energy use in non-industrial buildings for 13 countries. Various methods are used for the estimates, but they are mainly based on calculating the total annual enthalpy change needed for the conditioning of air. The potential for reduced energy use by improved ventilation control is also briefly reviewed.