Sage Journals: Discover world-class research

Abstract

The paper explains the philosophy of combining losses with solar gains through the modification of the conventional ‘U’ value used for windows. The definition of the modified value, called the “Effective ‘U’ value” is given in the form of an equation and a simple proof is given. The underlying research using detailed computer analysis of the energy requirements of buildings is discussed. Such computer analysis leads to the establishment of a methodology to determine effective ‘U‘ values for real situations. The methodology based on standard meteorological data and the thermal characteristics of glazing is explained and a program listing provided which enables the calculation to be made for any location and window design.

Get full access to this article

View all access options for this article.

References

1 Dufton, A. F. , Degree days, JIHVE, 2, 83–85 (1934). Knight, J. C. and Cornell, A. A., Degree days and Fuel Consumption for Office Buildings, JIHVE, 26, 309–326 (1959). Hitchin, E. R., Degree days in Britain, BSER&T, 2, (2) 73–82 (1981).

2 Hamilton, G., BSRIA Report Contract 3026 Report No. 1 (March 1980).

3 Ångström, A., Report to the International Commission for Solar Research in Actinometric investigations of Solar and atmospheric radiation. Quarterly Journal Royal Meteorological Society 50, 121–125 (1924).

4 Black, J. N , et al, Solar Radiation and duration of sunshine, QJRMS, 80, 231–235 (1954).

5 Berlage, H. P. , Zur Theorie der Beleuchtung einer horizontalen Flache durch Tageslicht. Meteorlogische Zeitschrift, 174–180 (May 1928).

6 Basnett, P., Estimation of Solar Radiation Falling on Vertical Surfaces from Measurements on a horizontal plane, ECRC/M846 (September 1975).