English

To develop guidance on effective ventilation strategies for buildings located in urban areas, it is necessary to have an understanding of the processes involved in the ingress of external pollution into buildings and its effect on indoor air quality. For naturally ventilated buildings, the combination of pressure forces and contaminant levels around the building is important in generating the level of internal contamination.

This paper describes the development of a model which can be used to explore the technical feasibility and policy implications of attempting to achieve 60 - 90% reductions in the C02 emissions from the UK housing stock by the middle of the next century. Reductions of this order are likely to be required across the industrialised countries in order to stabilise the atmospheric C02 concentration and global climate. In order to be able to investigate this problem, a highly disaggregated physically based energy and carbon dioxide model of the UK housing stock has been developed.

The conversion efficiency of solar cells is dependent on the cell temperature and they perform better the colder the cells are. The paper discusses cooling of solar cells by providing solar cell modules with an air gap behind the modules. The stack effect in the air gap drives the ventilation flow in a hybrid ventilation system. Expressions for the bulk flow properties (volumetric flow rate, mass flow rate and temperature) are presented as a function of the geometry of the air gap and the location of the heat input (configuration factor).

BSRIA are currently conducting a research project aimed at promoting identification and amelioration of plant oversizing, with particular emphasis on providing assessment of potential energy savings achievable through the application of remedial measures. The objective of the project is to update existing BSRIA guidance, which will provide building operators with information on how to identify excess HV AC plant capacity and how to enhance the performance of such plant.

The UK government has signed the Kyoto Protocol and it has committed to reducing C02 emissions to 20% below 1990 levels by 2010. As buildings are responsible for approximately half of the UK C02 emissions, of which the domestic sector accounts for 50%, meeting this target will require a significant contribution from the domestic sector.

Thirty five occupants of twenty five naturally ventilated rooms can operate supplementary cooling and heating equipment and windows independently to control their local thermal conditions and ventilation in accordance with their personal comfort requirements. Preliminary studies suggest that the use of the supplementary cooling equipment is closely related to outdoor thermal conditions with limited recourse to it in mild weather and resultant substantial energy saving in comparison with consumption that might be expected in a conventionally air conditioned environment.

Recent years have seen increased use of natural ventilation, daylighting, and cooling techniques in UK buildings. This paper describes the design and operating concept of a large, naturally ventilated and illuminated city centre library for Coventry University in the UK. The novel design concept includes four lightwells acting as ventilation inlets, each of which is fed with fresh air from a plenum below the ground floor. A central lightwell and perimeter stacks draw air across each floor plate and provide air extract routes.

This paper aims to identify major characteristics of hybrid ventilation systems, whereby a clear distinction is made between ventilation for Indoor air quality control and ventilation as part of a strategy for thermal comfort in summer. Various building projects are used as illustration for the classification.