energy use in buildings

The energy use in buildings is dependent on the choices made during the design, construction and renovation. The causes for these differences are, among others, caused by the behavior of the occupant of the building and the choice of heating and ventilation system. The European scheme of Energy Performance Certificates (EPCs) aims at reducing the energy use in the built environment. It is most common to calculate (i.e. not measure) the energy use for the buildings which are affected by the scheme.

In energy balance of buildings the ventilation losses are a big part, and this part is getting relatively bigger the better the enclosure of the building is insulated. All ventilation that is larger than what is wanted for hygiene and comfort can be regarded as undesired and thus be considered as heat loss. For energy conservation it is therefore essential that ventilation rate can be controlled. This report discusses the current research in Sweden dealing with air infiltration.

Fifty-nine owners/occupants of electrically heated houses in the Denver, Colorado area have, for about ten months, been participating in a study sponsored by the Electric Power Research Institute (EPRI) to determine theeffect of air infi

Building services accounts for some 40-50% of the UK's consumption of primary energy. The potential for energy saving through the adoption of such schemes as district heating, combined heat and power, heat pumps and solar energy could make a major contribution to the country's energy balance.

Use of spectral analysis as a tool in identifying correlations of annual and diurnal patterns of weather data is presented. Results obtained with the application of this technique to the 10-yr hourly data for six variables of Fresno, Calif., in the 1952-1963 period indicate significant correlations in the annual and diurnal patterns of the variables. A method is introduced for estimating coincident diurnal patterns, which can be used in load and energy studies. Considerations in selection of representative periods of weather data for standard usage are found to require further research.

This report describes a technique which models the infiltration process for an entire enclosure more accurately than standard methods. Both air flow and convective/conductive heat transfer are accounted for to (a) improve building heat load calculations, (b) determine the important characteristics of existing (and new) buildings for infiltration heat loads, and (c) account more accurately for wind effects.

If the energy losses due to ventilation have obviously become an important problem since the energy crisis, there is still a lot to be done with respect to the behaviours. Previous research has given results about the share of venti lation losses i n the energy balance, and the rational reasons to introduce fresh air into the house. Annex VIII is specialized in the attitudes of the inhabitants, in their habits with regard to ventilation and even in their apparent irrationality.

Measurements were carried out on the heating and airing habits of the occupants of several flats. 9 flats in a 6 storey building in Berlin, using various ventilation systems were studied. Two of the flats also had an air heating system. 

Discusses reasons behind occupant ventilating behaviour, such as: 1. general attitudes, particularly regarding energy, 2. occupant requirements, 3. components of the habitat micro-climate, 4. optimum micro-climate and desired micro-climate, 5. means available in the habitat to modify the micro-climate - a. general means, b. ventilation as a specific means, 6. balancing requirements against means, 7.

Reports a case study dealing with the relation between ventilating and airing behaviour and the outside climate. Also the significance of other variables such as preferences with respect to the indoor climate are considered. Wind speed is found to correlate, but outside temperature (varying from -3 to +9 degrees C) does not correlate with the length of time the windows in the bedrooms and bathrooms are opened. Rainfall and sunshine also seem to have some influence. The main reasons for airing are that the bedrooms are too warm and not fresh.