CLIMATE SURFACES - A QUANTITATIVE BUILDING-SPECIFIC REPRESENTATION OFCLIMATES

Based on the power balance equation, an analytical tool for the calcul ation of the free-run-temperature of a room has been developed and a u niversally valid energy-strategy derived. The description of the therm al behavior of a room is traced back in this approach to three paramet ers only: the generalized loss-factor K, the time constant tau and the gain-to-loss ratio gamma. By an appropriate inclusion of solar gains the usual definition of 'heating-degree-days' is extended to 'generali zed heating-degree-days', represented graphically as a function of tau and gamma. These two parameters yield the 'climate surface' of the ro om under consideration, A comparison with measured data from actual bu ildings confirms the validity of this approach. In order to illustrate its practical value, the method of climate-surfaces is applied in thi s paper to generate surfaces for design-temperature differences and to deduce optimized heating, cooling and control strategies, as well as strategies for the night set back, solar shading, night cooling etc. ( C) 1998 Elsevier Science S.A. All rights reserved.